JP2008209949A - Projection exposure device and projection exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection exposure device and a projection exposure method, capable of positioning a substrate at an appropriate position without using a position measuring device such as an interferometer for measuring the position of a stage. <P>SOLUTION: According to a position of a reference substrate reference mark formed on a reference substrate, table position correction data is calculated for correcting an error of position of the table. According to the table position correction data and the position of the exposure substrate reference mark formed on the exposure substrate, linear error correction data is calculated for correcting the error of the linear component of the position of the exposure substrate reference mark by using the method of least squares. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projection exposure apparatus and a projection exposure method for forming a pattern on an exposure substrate.

Conventionally, an exposure apparatus for a printed wiring board uses an alignment microscope to match the position of a reference mark formed on a reticle with the position of a reference mark formed on an exposure substrate, and then retracts the alignment microscope. Exposure was performed.
JP 2003-31014 A

  Since the projection exposure apparatus described above does not require an interferometer for measuring the position of the stage, it can be made inexpensive and is often used for exposure for printed wiring boards. However, the stage could not be accurately positioned. Even when an error occurs in the movement of the stage, the stage could not be positioned with high accuracy. Furthermore, the printed wiring board has a larger non-linear error than the wafer substrate, and there are cases where sufficient accuracy cannot be obtained by alignment using only the linear error correction used in the wafer substrate exposure apparatus.

  The present invention has been made in view of the above points, and an object of the present invention is to position a substrate at an appropriate position without using a position measuring device such as an interferometer for measuring the position of the stage. Another object of the present invention is to provide a projection exposure apparatus and a projection exposure method that can perform high-speed and high-precision alignment even for a printed wiring board having a large nonlinear error.

  In order to achieve the above object, in the present invention, the mounting table position correction data for correcting the error of the mounting table position is calculated based on the position of the reference substrate reference mark formed on the reference substrate. The linear error correction data for correcting the error of the linear component of the position of the exposure substrate reference mark based on the mounting table position correction data and the position of the exposure substrate reference mark formed on the exposure substrate Calculate using multiplication.

A projection exposure apparatus according to the present invention includes:
A projection exposure apparatus that irradiates a reticle on which a pattern is formed with exposure light and projects an image of the pattern onto an exposure substrate,
A driving stage for positioning the mounting table on which the substrate is mounted by moving it to at least four predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on a reference substrate capable of exposure;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate reference mark comprises at least four marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least four marks for indicating a reference position of the reference substrate,
The position determining means includes
First position correcting means for correcting an error in the position of the mounting table that occurs when the mounting table is moved;
Second position correcting means for correcting an error of a linear component of errors in the position of the exposure substrate reference mark,
The first position correcting means includes
Reference substrate position control means for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the drive stage when the reference substrate is mounted on the mounting table as the substrate. ,
A reference board position storage means for obtaining and storing the position of the mounting table at each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, exposure light is irradiated onto the reference reticle, and a reticle reference mark formed on the reference reticle is projected onto the reference substrate, thereby forming an image of the reticle reference mark on the reference substrate. A reference substrate exposure means for
The image of the reticle reference mark and the reference substrate reference mark formed on the reference substrate are detected by the reference mark detection means, and the image of the reticle reference mark and the reference substrate reference mark are relative to each other based on the detection result. A reference substrate position correction calculation storage means for calculating a position and calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the relative position and the position of the mounting table; Including
The second position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. Exposure substrate position control means for sequentially moving and positioning the table;
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. Exposure substrate reference mark position storage means for
Linear error correction for calculating linear error correction data for correcting an error of the linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storage means using a least square method And an arithmetic means.

[[[Overall description]]]
A projection exposure apparatus according to the present invention includes:
A projection exposure apparatus that irradiates a reticle on which a pattern is formed with exposure light and projects an image of the pattern onto an exposure substrate,
A driving stage for positioning the mounting table on which the substrate is mounted by moving it to at least four predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate reference mark comprises at least four marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least four marks for indicating a reference position of the reference substrate,
The position determining means includes
First position correcting means for correcting an error in the position of the mounting table that occurs when the mounting table is moved;
Second position correcting means for correcting an error of a linear component of errors in the position of the exposure substrate reference mark,
The first position correcting means includes
Reference substrate position control means for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the drive stage when the reference substrate is mounted on the mounting table as the substrate. ,
A reference board position storage means for obtaining and storing the position of the mounting table at each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, the reference substrate reference mark is detected by the reference mark detection means, and the position of the reference substrate reference mark is calculated and stored based on the detection result and the position of the mounting table. Reference board reference mark position storage means for
Reference substrate position correction calculation storage means for calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the position of the reference substrate reference mark,
The second position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. Exposure substrate position control means for sequentially moving and positioning the table;
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. Exposure substrate reference mark position storage means for
Linear error correction for calculating linear error correction data for correcting an error of the linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storage means using a least square method And an arithmetic means.

  Based on the value of the mounting table position correction data described above, by controlling the driving stage so as to correct the position of the mounting table, the mounting table is adjusted at the level of the formation error of the reference mark formed on the reference substrate. Can be positioned. For this reason, a pattern can be transferred to an exposure substrate by a global method without using a position measuring device such as an interferometer for measuring the position of the mounting table. By reducing the number of measurement points of the reference mark, it is possible to improve the positioning accuracy of the mounting table and also to increase the throughput of manufacturing the exposure substrate.

A projection exposure apparatus according to the present invention includes:
A digital micromirror device having a plurality of mirrors and capable of determining the reflection direction of light incident on the plurality of mirrors for each of the plurality of mirrors, and a plurality of micros each corresponding to each of the plurality of mirrors A projection exposure apparatus that projects an image of a spot formed by the microarray lens onto an exposure substrate.
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on a reference substrate capable of exposure;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
The position determining means includes
First position correcting means for correcting an error in the position of the mounting table that occurs when the mounting table is moved;
Second position correcting means for correcting an error of a linear component of errors in the position of the exposure substrate reference mark,
The first position correcting means includes
Reference substrate position control means for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the drive stage when the reference substrate is mounted on the mounting table as the substrate. ,
A reference board position storage means for obtaining and storing the position of the mounting table at each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, exposure light is irradiated onto the reference reticle, and a reticle reference mark formed on the reference reticle is projected onto the reference substrate, thereby forming an image of the reticle reference mark on the reference substrate. A reference substrate exposure means for
The image of the reticle reference mark and the reference substrate reference mark formed on the reference substrate are detected by the reference mark detection means, and the image of the reticle reference mark and the reference substrate reference mark are relative to each other based on the detection result. A reference substrate position correction calculation storage means for calculating a position and calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the relative position and the position of the mounting table; Including
The second position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. Exposure substrate position control means for sequentially moving and positioning the table;
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. Exposure substrate reference mark position storage means for
Linear error correction for calculating linear error correction data for correcting an error of the linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storage means using a least square method And an arithmetic means.

A projection exposure apparatus according to the present invention includes:
A digital micromirror device having a plurality of mirrors and capable of determining the reflection direction of light incident on the plurality of mirrors for each of the plurality of mirrors, and a plurality of micros each corresponding to each of the plurality of mirrors A projection exposure apparatus that projects an image of a spot formed by the microarray lens onto an exposure substrate.
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
The position determining means includes
First position correcting means for correcting an error in the position of the mounting table that occurs when the mounting table is moved;
Second position correcting means for correcting an error of a linear component of errors in the position of the exposure substrate reference mark,
The first position correcting means includes
Reference substrate position control means for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the drive stage when the reference substrate is mounted on the mounting table as the substrate. ,
A reference board position storage means for obtaining and storing the position of the mounting table at each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, the reference substrate reference mark is detected by the reference mark detection means, and the position of the reference substrate reference mark is calculated and stored based on the detection result and the position of the mounting table. Reference board reference mark position storage means for
Reference substrate position correction calculation storage means for calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the position of the reference substrate reference mark,
The second position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. Exposure substrate position control means for sequentially moving and positioning the table;
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. Exposure substrate reference mark position storage means for
Linear error correction for calculating linear error correction data for correcting an error of the linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storage means using a least square method And an arithmetic means.

  Based on the value of the mounting table position correction data described above, by controlling the driving stage so as to correct the position of the mounting table, the mounting table is adjusted at the level of the formation error of the reference mark formed on the reference substrate. Can be positioned. For this reason, a pattern can be transferred to an exposure substrate by a global method without using a position measuring device such as an interferometer for measuring the position of the mounting table. By reducing the number of measurement points of the reference mark, it is possible to improve the positioning accuracy of the mounting table and also to increase the throughput of manufacturing the exposure substrate.

  Moreover, a conductor pattern can be formed on an exposure substrate without using a reticle, and the shape of the conductor pattern can be made desired by controlling the digital micromirror device. Furthermore, by controlling the digital micromirror device, not only the degree of stretching but also the degree of orthogonality can be corrected.

A projection exposure apparatus according to the present invention includes:
A projection optical system that irradiates the exposure substrate with the exposure light;
The reference mark detection means includes an alignment optical system disposed between the projection optical system and the mounting table.
The alignment optical system irradiates the exposure substrate reference mark or the reference substrate reference mark with non-exposure light, and detects the exposure substrate reference mark or the reference substrate reference mark.
The alignment optical system includes:
When detecting the exposure substrate reference mark, or the reference substrate reference mark, is positioned at the detection position,
When the detection of the exposure substrate reference mark or the reference substrate reference mark is finished, the exposure substrate reference mark is positioned at the retracted position retracted from the detection position.

  By irradiating the reference substrate reference mark with non-exposure light, the reference mark can be accurately detected. Also, when detecting multiple fiducial marks, after measuring the position of the last fiducial mark, the alignment optical system is retracted and exposure is started, so there is no need to move the alignment optical system in each of the multiple exposure areas Since the time required for detecting the reference mark can be shortened, the throughput can be increased.

A projection exposure apparatus according to the present invention includes:
The mounting table position correction data is calculated based on an average value of the positions of the exposure substrate reference marks at a plurality of reference substrate detection positions.

  This is the case where an error occurs in the movement of the drive stage or an Abbe error due to a slight tilt of the drive stage by calculating the mounting table position correction data based on the average position of the exposure substrate reference mark. However, the positioning accuracy of the mounting table can be further increased.

A projection exposure apparatus according to the present invention includes:
The reference substrate reference mark is formed on the reference substrate so as to be located at a grid-like intersection of predetermined intervals,
The mounting table position correction data is data calculated based on the position of the reference substrate reference mark located at the grid intersection,
The exposure substrate position control means calculates a target position for positioning the mounting table by curve approximation or interpolation using the mounting table position correction data, and controls the positioning to position the mounting table at the target position.

  When the error gradually changes with respect to the position of the mounting table, the time for measuring the position of the reference mark is obtained by obtaining interpolation data by curve approximation or interpolation calculation using the mounting table position correction data. It is possible to shorten the time, to reduce the storage capacity occupied by the mounting table position correction data, and it is possible to shorten the time for the calculation performed before moving the drive stage.

A projection exposure apparatus according to the present invention includes:
A projection optical system capable of projecting the pattern onto the exposure substrate by changing a projection magnification of the image of the pattern;
Projection magnification determination means for determining the projection magnification based on the linear error correction data calculated by the linear error correction calculation means.

  Since the linear error correction data is obtained as a result of the long dimension measurement, it is possible to obtain an averaging effect by the least square approximation calculation. Based on this result, the projection magnification is corrected to accurately determine the pattern. It can be transferred to an exposure substrate with a large size.

  In particular, the parameters based on the linear error correction data include, for example, an X-direction elasticity and a Y-direction elasticity. When a projection optical system designed asymmetrically is used, the magnification in the X direction and the Y direction can be corrected independently, and the pattern can be transferred onto the exposure substrate more accurately.

A projection exposure apparatus according to the present invention includes:
A projection exposure apparatus that irradiates a reticle on which a pattern is formed with exposure light and projects an image of the pattern onto an exposure substrate,
A driving stage for positioning the mounting table on which the substrate is mounted by moving it to at least four predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate has at least four exposure areas on which an image of the pattern is projected;
The exposure substrate reference mark is an exposure area reference mark indicating a reference position of the at least four exposure areas,
The position determining means includes an exposure position correcting means for correcting an error in the position of the exposure substrate reference mark,
The exposure position correcting means includes
Exposure substrate position control means for sequentially moving and positioning the mounting table to at least four or more predetermined exposure substrate detection positions by the drive stage when the exposure substrate is mounted on the mounting table as the substrate. When,
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure area reference mark, and calculates and stores the position of the exposure area reference mark based on the detection result and the position of the mounting table. Exposure area reference mark position storage means for performing,
Based on the position of the exposure area reference mark stored in the exposure substrate reference mark position storage means, error information of a non-linear component of errors in the position of the exposure substrate reference mark is calculated using a least square method. Position error processing means;
Based on the difference in the position of the exposure area reference mark stored in the exposure substrate reference mark position storage means, the error information of the nonlinear component of the difference in the difference in position of the exposure substrate reference mark is used by the least square method. Differential error processing means for calculating
Exposure substrate position determining means for calculating a target position for positioning the mounting table by weighting based on error information of at least one of the two nonlinear components, and for positioning the mounting table at the target position. Features.

  The target position for positioning the mounting table is calculated by weighting the error of the linear component and the error of the nonlinear component, so stage control close to the die-by-die method and stage control close to the global method are performed according to the state of the exposure substrate. The accuracy of positioning the mounting table can be improved. Here, “weighting” is only the magnitude of the non-linear error and the linear error. In addition to selecting either the die-by-die method or the global method, it depends on the size of the non-linear error and the linear error. Means to calculate a target position.

A projection exposure apparatus according to the present invention includes:
A projection exposure apparatus that irradiates a reticle on which a pattern is formed with exposure light and projects an image of the pattern onto an exposure substrate,
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
Reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate has at least three exposure areas on which an image of the pattern is projected;
The exposure substrate reference mark is an exposure area reference mark indicating a reference position of the at least three exposure areas,
The position determining means includes an exposure position correcting means for correcting an error in the position of the exposure substrate reference mark,
The exposure position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, exposure substrate position control means for sequentially moving the mounting table to at least three or more predetermined exposure substrate detection positions by the drive stage. When,
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure area reference mark, and calculates and stores the position of the exposure area reference mark based on the detection result and the position of the mounting table. Exposure area reference mark position storage means for performing,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure area reference mark stored in the exposure area reference mark position storage means using a least square method Means,
Difference calculating means for calculating a difference between the positions of the exposure area reference marks stored in the exposure substrate reference mark position storage means;
Replacing at least one of expansion / contraction, rotation and orthogonality obtained by the least square method with the difference, irradiating the reticle with exposure light, and projecting an image of the pattern onto an exposure substrate; and And overlay control means for calculating and controlling the overlay target position with the exposure substrate.

  Since at least one of expansion, contraction, rotation, and orthogonality obtained by the least square method is replaced with a difference, the processing can be simplified and the throughput of manufacturing the substrate can be increased.

The projection exposure method according to the present invention includes:
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on a reference substrate capable of exposure;
A projection exposure apparatus including a position determining unit for determining the position of the mounting table based on the position indicated by the position signal, and irradiating the reticle on which the pattern is formed with exposure light, A projection exposure method for projecting an image of the pattern onto the exposure substrate placed on a mounting table,
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
A reference substrate position control step for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the driving stage when the reference substrate is mounted on the mounting table as the substrate; ,
A reference substrate position storing step for obtaining and storing the position of the mounting table in each of the reference substrate detection positions from the position signal;
At each of the reference substrate detection positions, exposure light is irradiated onto the reference reticle, and a reticle reference mark formed on the reference reticle is projected onto the reference substrate, thereby forming an image of the reticle reference mark on the reference substrate. A reference substrate exposure step,
The image of the reticle reference mark and the reference substrate reference mark formed on the reference substrate are detected by the reference mark detection means, and the image of the reticle reference mark and the reference substrate reference mark are relative to each other based on the detection result. A reference substrate position correction calculation storage step for calculating a position and calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the relative position and the position of the mounting table;
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. An exposure substrate position control step for sequentially moving and positioning the mounting table;
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. An exposure substrate reference mark position storing step,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storing step using a least square method And a step.

The projection exposure method according to the present invention includes:
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
A projection exposure apparatus including a position determining unit for determining the position of the mounting table based on the position indicated by the position signal, and irradiating the reticle on which the pattern is formed with exposure light, A projection exposure method for projecting an image of the pattern onto the exposure substrate placed on a mounting table,
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
A reference substrate position control step for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the driving stage when the reference substrate is mounted on the mounting table as the substrate; ,
A reference board position storing step for obtaining and storing the position of the mounting table in each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, the reference substrate reference mark is detected by the reference mark detection means, and the position of the reference substrate reference mark is calculated and stored based on the detection result and the position of the mounting table. A reference board reference mark position storing step,
A reference substrate position correction calculation storage step for calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the position of the reference substrate reference mark;
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. An exposure substrate position control step for sequentially moving and positioning the mounting table;
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. An exposure substrate reference mark position storing step,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storing step using a least square method And a step.

  Based on the value of the mounting table position correction data described above, by controlling the driving stage so as to correct the position of the mounting table, the mounting table is adjusted at the level of the formation error of the reference mark formed on the reference substrate. Can be positioned. For this reason, a pattern can be transferred to an exposure substrate by a global method without using a position measuring device such as an interferometer for measuring the position of the mounting table. By reducing the number of measurement points of the reference mark, it is possible to improve the positioning accuracy of the mounting table and also to increase the throughput of manufacturing the exposure substrate.

The projection exposure method according to the present invention includes:
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on a reference substrate capable of exposure;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
A digital micromirror device having a plurality of mirrors and capable of determining the reflection direction of light incident on the plurality of mirrors for each of the plurality of mirrors;
The image of the spot formed by the microarray lens was placed on the mounting table using a projection exposure apparatus including a microarray lens having a plurality of microlenses corresponding to each of the plurality of mirrors. A projection exposure method for projecting onto the exposure substrate,
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
A reference substrate position control step for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the driving stage when the reference substrate is mounted on the mounting table as the substrate; ,
A reference board position storing step for obtaining and storing the position of the mounting table in each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, exposure light is irradiated onto the reference reticle, and a reticle reference mark formed on the reference reticle is projected onto the reference substrate, thereby forming an image of the reticle reference mark on the reference substrate. A reference substrate exposure step,
The image of the reticle reference mark and the reference substrate reference mark formed on the reference substrate are detected by the reference mark detection means, and the image of the reticle reference mark and the reference substrate reference mark are relative to each other based on the detection result. A reference substrate position correction calculation storage step for calculating a position and calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the relative position and the position of the mounting table;
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. An exposure substrate position control step for sequentially moving and positioning the mounting table;
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. An exposure substrate reference mark position storing step,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storing step using a least square method And a step.

The projection exposure method according to the present invention includes:
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
A digital micromirror device having a plurality of mirrors and capable of determining the reflection direction of light incident on the plurality of mirrors for each of the plurality of mirrors;
The image of the spot formed by the microarray lens was placed on the mounting table using a projection exposure apparatus including a microarray lens having a plurality of microlenses corresponding to each of the plurality of mirrors. A projection exposure method for projecting onto the exposure substrate,
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
A reference substrate position control step for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the driving stage when the reference substrate is mounted on the mounting table as the substrate; ,
A reference board position storing step for obtaining and storing the position of the mounting table in each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, the reference substrate reference mark is detected by the reference mark detection means, and the position of the reference substrate reference mark is calculated and stored based on the detection result and the position of the mounting table. A reference board reference mark position storing step,
A reference substrate position correction calculation storage step for calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the position of the reference substrate reference mark;
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. An exposure substrate position control step for sequentially moving and positioning the mounting table;
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. An exposure substrate reference mark position storing step,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storing step using a least square method And a step.

  Based on the value of the mounting table position correction data described above, by controlling the driving stage so as to correct the position of the mounting table, the mounting table is adjusted at the level of the formation error of the reference mark formed on the reference substrate. Can be positioned. For this reason, a pattern can be transferred to an exposure substrate by a global method without using a position measuring device such as an interferometer for measuring the position of the mounting table. By reducing the number of measurement points of the reference mark, it is possible to improve the positioning accuracy of the mounting table and also to increase the throughput of manufacturing the exposure substrate.

  Moreover, a conductor pattern can be formed on an exposure substrate without using a reticle, and the shape of the conductor pattern can be made desired by controlling the digital micromirror device. Furthermore, by controlling the digital micromirror device, not only the degree of stretching but also the degree of orthogonality can be corrected.

The projection exposure method according to the present invention includes:
The projection exposure apparatus includes a projection optical system that irradiates the exposure substrate with the exposure light,
The reference mark detection means is disposed between the projection optical system and the mounting table, and irradiates the exposure substrate reference mark or the reference substrate reference mark with non-exposure light, and the exposure substrate reference mark, or An alignment optical system for detecting the reference substrate reference mark,
When detecting the reference substrate reference mark or the exposure substrate reference mark by the reference mark detection means,
When detecting the exposure substrate reference mark or the reference substrate reference mark, positioning the alignment optical system at a detection position;
And positioning the alignment optical system at the retracted position retracted from the detection position when the detection of the exposure substrate reference mark or the reference substrate reference mark is completed.

  By irradiating the reference substrate reference mark with non-exposure light, the reference mark can be accurately detected. Also, when detecting multiple fiducial marks, after measuring the position of the last fiducial mark, the alignment optical system is retracted and exposure is started, so there is no need to move the alignment optical system in each of the multiple exposure areas Since the time required for detecting the reference mark can be shortened, the throughput can be increased.

The projection exposure method according to the present invention includes:
The mounting table position correction data is calculated based on an average value of the positions of the exposure substrate reference marks at a plurality of reference substrate detection positions.

  This is the case where an error occurs in the movement of the drive stage or an Abbe error due to a slight tilt of the drive stage by calculating the mounting table position correction data based on the average position of the exposure substrate reference mark. However, the positioning accuracy of the mounting table can be further increased.

The projection exposure method according to the present invention includes:
The reference substrate reference mark is formed so as to be located at a grid-like intersection of predetermined intervals in the reference substrate,
The mounting table position correction data is data calculated based on the position of the reference substrate reference mark located at the grid intersection,
The method includes a step of calculating a target position for positioning the mounting table by using a curve approximation or interpolation method using the mounting table position correction data, and controlling the positioning to position the mounting table at the target position.

  When the error gradually changes with respect to the position of the mounting table, the time for measuring the position of the reference mark is obtained by obtaining interpolation data by curve approximation or interpolation calculation using the mounting table position correction data. It is possible to shorten the time, to reduce the storage capacity occupied by the mounting table position correction data, and it is possible to shorten the time for the calculation performed before moving the drive stage.

The projection exposure method according to the present invention includes:
A projection optical system capable of changing the projection magnification of the image of the pattern and projecting the pattern onto the exposure substrate;
Determining the projection magnification based on the linear error correction data calculated in the linear error correction calculation step.

  Since the linear error correction data is obtained as a result of the long dimension measurement, it is possible to obtain an averaging effect by the least square approximation calculation. Based on this result, the projection magnification is corrected to accurately determine the pattern. It can be transferred to an exposure substrate with a large size.

  In particular, the parameters based on the linear error correction data include, for example, an X-direction elasticity and a Y-direction elasticity. When a projection optical system designed asymmetrically is used, the magnification in the X direction and the Y direction can be corrected independently, and the pattern can be transferred onto the exposure substrate more accurately.

The projection exposure method according to the present invention includes:
A driving stage for positioning the mounting table on which the substrate is mounted by moving it to at least four predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
A projection exposure apparatus including a position determining unit for determining the position of the mounting table based on the position indicated by the position signal, and irradiating the reticle on which the pattern is formed with exposure light, A projection exposure method for projecting an image of the pattern onto the exposure substrate placed on a mounting table,
The exposure substrate has at least four exposure areas on which an image of the pattern is projected;
The exposure substrate reference mark is an exposure area reference mark indicating a reference position of the at least four exposure areas,
An exposure substrate position control step of sequentially moving and positioning the mounting table to at least four or more predetermined exposure substrate detection positions by the drive stage when the exposure substrate is mounted on the mounting table as the substrate. When,
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure area reference mark, and calculates and stores the position of the exposure area reference mark based on the detection result and the position of the mounting table. An exposure area reference mark position storing step;
Based on the position of the exposure area reference mark stored in the exposure substrate reference mark position storing step, error information of a non-linear component of errors in the position of the exposure substrate reference mark is calculated using a least square method. A position error processing step;
Based on the difference in the position of the exposure area reference mark stored in the exposure substrate reference mark position storage means, the error information of the non-linear component of the difference in the difference in position of the exposure substrate reference mark is used by the least square method. Differential error processing step to calculate,
A step of calculating a target position for positioning the mounting table by weighting based on error information of at least one of the two nonlinear components, and determining an exposure substrate position for positioning the mounting table at the target position. Features.

  The target position for positioning the mounting table is calculated by weighting the error of the linear component and the error of the nonlinear component, so stage control close to the die-by-die method and stage control close to the global method are performed according to the state of the exposure substrate. The accuracy of positioning the mounting table can be improved. Here, “weighting” is only the magnitude of the non-linear error and the linear error. In addition to selecting either the die-by-die method or the global method, it depends on the size of the non-linear error and the linear error. Means to calculate a target position.

The projection exposure method according to the present invention includes:
A projection exposure method for projecting an image of a pattern onto an exposure substrate by irradiating exposure light onto a reticle on which a pattern is formed, wherein the mounting table on which the substrate is mounted is moved to at least three predetermined positions A driving stage positioned
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
A projection exposure apparatus including a position determining unit for determining the position of the mounting table based on the position indicated by the position signal, and irradiating the reticle on which the pattern is formed with exposure light, A projection exposure method for projecting an image of the pattern onto the exposure substrate placed on a mounting table,
The exposure substrate has at least three exposure areas on which an image of the pattern is projected;
The exposure substrate reference mark is an exposure area reference mark indicating a reference position of the at least three exposure areas,
An exposure substrate position control step for sequentially moving and positioning the mounting table to at least three predetermined exposure substrate detection positions by the drive stage when the exposure substrate is mounted on the mounting table as the substrate. When,
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure area reference mark, and calculates and stores the position of the exposure area reference mark based on the detection result and the position of the mounting table. An exposure area reference mark position storing step;
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure area reference mark stored in the exposure area reference mark position storage means using a least square method Steps,
A difference calculating step of calculating a difference between the positions of the exposure area reference marks stored in the exposure substrate reference mark position storing step;
Replacing at least one of expansion / contraction, rotation and orthogonality obtained by the least square method with the difference, irradiating the reticle with exposure light, and projecting an image of the pattern onto an exposure substrate; and And a superposition control step for calculating and controlling a superposition target position with the exposure substrate.

  Since at least one of expansion, contraction, rotation, and orthogonality obtained by the least square method is replaced with a difference, the processing can be simplified and the throughput of manufacturing the substrate can be increased.

  Without using a position measuring device such as an interferometer for measuring the position of the stage, the substrate can be positioned at an accurate position at high speed. Furthermore, sufficient alignment accuracy can be obtained even in a printed wiring board having a large non-linear error compared to the wafer substrate.

  Embodiments of the present invention will be described below with reference to the drawings.

<<<< first embodiment >>>>
FIG. 1 schematically shows a projection exposure apparatus 100 according to the first embodiment of the present invention. The projection exposure apparatus 100 is mainly for manufacturing a printed wiring board.

<<< Configuration >>>
<< Projection optical system >>
<Light source 110>
A light source 110 that emits a light beam having a desired wavelength is used. For example, a lamp that emits ultraviolet rays having a short wavelength, such as a mercury lamp, can be used. In the bulb of the light source 110, mercury, which is a luminescent material, and two electrodes, an anode (not shown) and a cathode (not shown), are enclosed. The cathode and the anode are arranged to face each other. Each electrode is electrically connected to a metal conductor (not shown), and an arc discharge is formed between the cathode and the anode.

  One base 112a of the light source 110 is fixed to a support member (not shown) provided outside an elliptical mirror 120 described later. The other base 112b is connected to a power cable (not shown). The light source 110 is discharged when a predetermined voltage is applied to both electrodes through these caps. Note that the power cable has a small diameter and does not interfere with the light beam emitted from the light source 110.

  When arc discharge is generated between the anode and the cathode, strong light emission is generated from a discharge portion called an arc column. The luminous flux emitted from this arc column is divergent light spreading in all directions.

<Oval mirror 120>
The elliptical mirror 120 condenses the light beam emitted from the light source 110. As shown in FIG. 1, the elliptical mirror 120 has a reflective surface 122, and the elliptical mirror 120 is a reflective mirror in which the shape of the reflective surface 122 is a spheroid. A through hole 126 is formed at the bottom of the elliptical mirror 120. A part of the light source 110 is disposed in the through hole 126. By disposing a part of the light source 110 in the through hole 126, the light source 110 can be positioned so that the arc portion of the light source 110 is positioned at the first focal point of the elliptical mirror 120.

  As described above, once the light beam emitted from the light source 110 is collected by the elliptical mirror 120, the illuminance of the light beam can be increased. By doing in this way, the utilization efficiency of the light beam emitted from the light source 110 can be improved.

  As described above, in the illumination device according to the present invention, the elliptical mirror 120 is used for the condensing optical system. The elliptical mirror 120 has two focal points, a first focal point and a second focal point, and the light source 110 has a support member (so that the arc portion of the light source 110 is positioned at the first focal point of the elliptical mirror 120. (Not shown). By doing so, the light beam emitted from the light source 110 is reflected by the reflecting surface 122 of the elliptical mirror 120 and collected at the second focal point.

<Rod 130>
The rod 130 has a long rectangular parallelepiped shape. The rod 130 has an entrance surface 132 and an exit surface 134. The rod 130 is arranged so that the light source image conjugate plane of the rod 130 is optically located at the second focal point of the elliptical mirror 120 or at a point conjugate with the second focal point. Further, the rod 130 is disposed so that the emission surface 134 of the rod 130 is in a conjugate position with a pattern forming surface 144 of a reticle 142 described later.

  A light beam emitted from the light source 110 is incident on the incident surface 132 of the rod 130. The rod 130 is for making the illuminance of the light beam incident on the incident surface 132 uniform. From the exit surface 134 of the rod 130, a light flux having a uniform illuminance is emitted. The rod 130 only needs to be able to illuminate with the light flux incident on the incident surface 132 with the illuminance approaching uniform.

<Light guiding optical system 140>
The light guide optical system includes a reflection mirror 136, an illumination relay optical system 138, and a reflection mirror 140. The travel direction of the light beam emitted from the exit surface 134 of the rod 130 is changed by the reflection mirror 136, the cross-sectional size is enlarged by the illumination relay optical system 138, and the travel direction is changed again by the reflection mirror 140. Then, it enters a reticle 142 to be described later.

<Reticle 142>
The reticle 142 is a photomask used for forming a conductor pattern on an exposure substrate 156 (156a, 156b or 156c) to be described later when a printed wiring board is manufactured. The reticle 142 corresponds to a negative for transferring a pattern formed on the reticle 142 to the exposure substrate 156 by exposure light emitted from the light source 110 and forming a conductor pattern on the exposure substrate 156. A pattern corresponding to the conductor pattern to be formed on the exposure substrate 156 is formed on the pattern forming surface 144 of the reticle 142.

  The exposure substrate 156 is composed of a substrate such as a copper-clad laminate, and is a substrate before a conductor pattern is formed, and the surface is covered with a photosensitive substance such as a resist. Moreover, a conductor pattern says the figure formed with a conductive material with a printed wiring board. Further, the printed wiring board refers to a substrate in which a conductor pattern is formed on the exposure substrate 156.

  As described above, the light beam that is emitted from the exit surface 134 of the rod 130 and whose traveling direction is changed to the reflection mirror 140 illuminates the pattern forming surface 144 of the reticle 142.

<Reticle blind 146>
A reticle blind 146 is disposed in the vicinity above the reticle 142. The reticle blind 146 includes a movable plate 148 that can move while being parallel to the reticle 142. In the example shown in FIG. 1, the reticle 142 is held horizontally, and the movable plate 148 of the reticle blind 146 can move in the horizontal direction as indicated by a white arrow. The reticle blind 146 blocks part of the light beam emitted from the exit surface 134 of the rod 130 and changes the cross section of the light beam to a desired size. The light beam whose cross section has been changed is irradiated onto the reticle 142 described above.

<Projection lens 150>
A projection lens 150 is provided below the reticle 142 described above. The projection lens 150 has an entrance surface 152 and an exit surface 154, and is supported by a support member (not shown) so that the entrance surface 152 is located on the upper side and the exit surface 154 is located on the lower side. It has been.

  The light beam that has passed through the reticle 142 is incident on the incident surface 152 of the projection lens 150. The projection lens 150 is composed of at least one or more types of lenses, and inside the projection lens 150, the size of the cross section of the light beam incident on the incident surface 152 is set to a desired size by these lenses. The converted light flux is emitted from the exit surface 154. By doing so, the projection lens 150 changes the size of the pattern image formed on the pattern forming surface 144 of the reticle 142 described later, and the pattern image is projected onto the exposure substrate 156 described later. The formed pattern can be transferred onto the exposure substrate 156 in a desired size. Note that the projection lens 150 is preferably composed of an equal magnification projection optical system.

<< Alignment optical system 160 >>
The alignment optical system 160 photographs an exposure substrate 156 (156a, 156b or 156c) to be described later and a substrate reference mark formed on the reference substrate 158 (158a or 158b), and determines the position of the substrate reference mark. It is an optical system. The alignment optical system 160 is placed on a movable stage (not shown) and positioned at the retracted position and the measurement position. The retracted position and measurement position will be described later.

  The alignment optical system 160 is also used to determine the position of the table reference mark by photographing the table reference mark 179 formed on the table 177 of the substrate mounting stage 170 described later.

  The alignment optical system 160 includes two microscopes 162a and 162b. Each of the microscopes 162a and 162b includes an image pickup device (not shown) such as a CCD camera, and can photograph a substrate reference mark and a table reference mark. An image processing device 164 is electrically connected to the imaging elements of the microscopes 162a and 162b. The image processing apparatus 164 captures images taken by the microscopes 162a and 162b as image data, processes the image data, etc., extracts a substrate reference mark image and a table reference mark image, and extracts the position of the substrate reference mark. The position of the table reference mark is determined and stored.

  In the example shown in FIG. 1, there is only one alignment optical system 160, which is arranged on the lower left side of the projection lens 150. However, two optical systems are provided as the alignment optical systems 160a and 160b. Also good. In this case, like the alignment optical system 160, the alignment optical system 160a is disposed on the lower left side of the projection lens 150, and the alignment optical system 160b is disposed on the lower right side of the projection lens 150 (not shown). Each of the alignment optical systems 160a and 160b has the same configuration as that of the alignment optical system 160. Each of the alignment optical systems 160a and 160b has two microscopes and can photograph a substrate reference mark and a table reference mark. Further, an image processing device 164 is electrically connected to each of the alignment optical systems 160a and 160b, and images taken by each of the alignment optical systems 160a and 160b can be processed. Thus, when two alignment optical systems are used, the processing can be speeded up as will be described later.

<< Substrate Placement Stage 170 >>
As shown in FIG. 1, a substrate placement stage 170 is provided below the projection lens 150. The substrate placement stage 170 includes an X direction moving stage 172, a Y direction moving stage 174, and a Z direction moving stage 176. In FIG. 1, the right direction of the drawing indicates the + X direction, the depth direction of the drawing indicates the + Y direction, and the upward direction of the drawing indicates the + Z direction. A table 177 (not shown) for horizontally placing the exposure substrate 156 is formed on the upper surface of the Z-direction moving stage 176.

  A table reference mark 179 (not shown) is formed on a part of the upper surface of the table 177 for alignment with the reticle reference mark (not shown) formed on the reticle 142 described above. Yes. The reticle reference mark is a reference mark for indicating the reference position of the reticle 142. The alignment of the table reference mark 179 when the position of the image when the reticle reference mark is projected onto the table 177 (hereinafter referred to as the image of the reticle reference mark) and the position of the table reference mark 179 coincide with each other. The image is taken by the system 160 and the position of the table reference mark 179 is stored. When the pattern formed on the reticle 142 is projected onto the exposure substrate 156, the stored position of the table reference mark 179 and the position of the substrate reference mark are matched so that the pattern formed on the reticle 142 is , And can be projected onto a desired exposure region of the exposure substrate 156.

<X direction moving stage 172, Y direction moving stage 174>
2A is a front view showing details of the X direction moving stage 172 and the Y direction moving stage 174, and FIG. 2B is a front view showing details of the X direction moving stage 172. As shown in FIG. is there. 2A and 2B, the right direction in the drawing indicates the + X direction, and the upward direction in the drawing indicates the + Y direction.

  The substrate mounting stage 170 has long surface plates 178a and 178b. Each of the surface plates 178a and 178b is fixed to a predetermined table (not shown).

  The surface plate 178a is provided with a linear motor stator 180a and a linear encoder stator 182a. The linear motor stator 180a and the linear encoder stator 182a have a long shape. The linear motor stator 180a and the linear encoder stator 182a are provided on the surface plate 178a so as to be parallel to each other and along the longitudinal direction of the surface plate 178a.

  The surface plate 178b is also provided with a linear motor stator 180b and a linear encoder stator 182b. The linear motor stator 180b and the linear encoder stator 182b have a long shape. The linear motor stator 180b and the linear encoder stator 182b are provided on the surface plate 178b so as to be parallel to each other and along the longitudinal direction of the surface plate 178b.

  The platen 178a is provided with an elongated linear guide 188a between the linear motor stator 180a and the linear encoder stator 182a. The platen 178b is provided with a long linear guide 188b between the linear motor stator 180b and the linear encoder stator 182b.

  On the left side of the lower surface of the Y-direction moving stage 174, a linear motor movable element 184a is provided so as to correspond to the linear motor stator 180a. A linear motor movable element 184b is provided on the right side of the lower surface of the Y-direction moving stage 174 so as to correspond to the linear motor stator 180b. By supplying current to the linear motor movable elements 184a and 184b, the linear motor movable element 184a moves along the linear motor stator 180a while being guided by the linear guide 188a, and the linear motor movable element 184b While moving along the linear motor stator 180b while being guided by 188b, the Y-direction moving stage 174 can be moved to a desired position in the ± Y direction.

  On the left side of the lower surface of the Y-direction moving stage 174, a linear encoder mover 186a is also provided so as to correspond to the linear encoder stator 182a. A signal indicating the position of the linear encoder movable element 186a with respect to the linear encoder stator 182a is generated from the linear encoder movable element 186a.

  A linear encoder movable element 186b is also provided on the right side of the lower surface of the Y-direction moving stage 174 so as to correspond to the linear encoder stator 182b. A signal indicating the position of the linear encoder mover 186b relative to the linear encoder stator 182b is generated from the linear encoder mover 186b.

  A control device 199 is connected to the Y-direction moving stage 174. The control device 199 receives the signal emitted from the linear encoder movable element 186a and the signal emitted from the linear encoder movable element 186b, thereby obtaining the position and moving distance in the Y direction of the Y-direction moving stage 174. it can. When the Y-direction moving stage 174 is moved in the ± Y direction, the control device 199 receives a signal generated from the linear encoder movable element 186a and a signal generated from the linear encoder movable element 186b, and receives the linear encoder movable element. Based on the positions of 186a and 186b, the current supplied to the linear motor movable elements 184a and 184b is controlled.

  Further, by moving the linear encoder movers 186a and 186b in the same direction, the Y-direction moving stage 174 can be translated in the ± Y directions. Further, the Y-direction moving stage 174 can be rotated to some extent clockwise or counterclockwise by moving the linear encoder movable elements 186a and 186b by different distances or by moving them in opposite directions.

FIG. 2B is a front view showing details of the X-direction moving stage 172.
As shown in FIG. 2B, a linear motor stator 190 and a linear encoder stator 192 are provided on the upper part of the Y-direction moving stage 174. The linear motor stator 190 and the linear encoder stator 192 have a long shape. The linear motor stator 190 and the linear encoder stator 192 are provided on the Y direction moving stage 174 so as to be parallel to each other and along the longitudinal direction of the Y direction moving stage 174. The Y-direction moving stage 174 is provided with a long linear guide 194 between the linear motor stator 190 and the linear encoder stator 192.

  A linear motor movable element 196 is provided on the lower surface of the X-direction moving stage 172 so as to correspond to the linear motor stator 190. By supplying current to the linear motor movable element 196, the linear motor movable element 196 moves along the linear motor stator 190 while being guided by the linear guide 194, and as a result, the X-direction moving stage 172 is moved ± It can be moved to a desired position in the X direction.

  A linear encoder movable element 198 is also provided on the lower surface of the X direction moving stage 172 so as to correspond to the linear encoder stator 192. A signal indicating the position of the linear encoder mover 198 relative to the linear encoder stator 192 is generated from the linear encoder mover 198.

  A control device 199 is also connected to the X-direction moving stage 172. The control device 199 can obtain the position and movement distance of the X-direction moving stage 172 by receiving a signal emitted from the linear encoder mover 198. As described above, since the Y-direction moving stage 174 can be rotated clockwise or counterclockwise to some extent, the signal generated from the linear encoder mover 198 is transmitted in the longitudinal direction of the Y-direction moving stage 174. The position of the X direction moving stage 172 is shown. When the X-direction moving stage 172 is moved in the direction along the longitudinal direction of the Y-direction moving stage 174, the control device 199 receives a signal generated from the linear encoder mover 198 and receives the linear encoder mover 198. Based on this position, the current supplied to the linear motor movable element 196 is controlled.

  The signals generated from the linear encoder movable elements 186a and 186b described above are signals in the Y direction of the Y direction moving stage 174 in the coordinate system fixed to the surface plates 178a and 178b with the home position of the Y direction moving stage 174 as the origin. Indicates the position. The signal generated from the linear encoder movable element 198 indicates the position of the X direction moving stage 172 in the coordinate system fixed to the Y direction moving stage 174 with the home position of the X direction moving stage 172 as the origin. This position is a position along the longitudinal direction of the Y-direction moving stage 174. As described above, since the X-direction moving stage 172 is provided above the Y-direction moving stage 174, the control device 199 also obtains signals emitted from the linear encoder movers 186a and 186b. The position of the X-direction moving stage 172 can be converted to a position in a coordinate system fixed to the surface plates 178a and 178b.

  By doing so, the control device 199 receives the signal emitted from the linear encoder movable element 186a, the signal emitted from the linear encoder movable element 186b, and the signal emitted from the linear encoder movable element 198, The Y-direction position and rotational position of the Y-direction moving stage 174 in the coordinate system fixed to the surface plates 178a and 178b can be obtained, and the X-direction moving stage 172 in the coordinate system fixed to the surface plates 178a and 178b. The position in the X direction can be obtained.

<Z-direction moving stage 176>
FIG. 3 is a side view showing details of the Z-direction moving stage 176. In FIG. 3, the left direction in the drawing indicates the + Y direction, and the depth direction in the drawing indicates the + X direction. FIG. 3A shows the Y-direction moving stage 174 positioned at the extreme end in the −Y direction, and FIG. 3B shows the Y-direction moving stage 174 at the extreme end in the + Y direction. It is the one when it is positioned.

  A Z-direction moving stage 176 is provided above the X-direction moving stage 172. As described above, the table 177 for placing the exposure substrate 156 is formed on the upper surface of the Z-direction moving stage 176. The Z-direction moving stage 176 has a tilt drive motor (not shown) for making the Z-direction moving stage 176 tilt with respect to the horizontal as well as translationally moving in the ± Z directions. By controlling the tilt drive motor, the table 177 of the Z-direction moving stage 176 can be tilted by a desired angle with respect to the horizontal.

  As shown in FIGS. 3A and 3B, the exposure substrate 156 is placed on the table 177 of the Z-direction moving stage 176. By tilting the Z-direction moving stage 176 with the tilt mechanism described above, the exposure substrate 156 placed on the table 177 of the Z-direction moving stage 176 can be tilted with respect to the horizontal by a desired angle. .

  Further, as shown in FIGS. 3A and 3B, the white arrow pointing downward indicates the light beam emitted from the exit surface 154 of the projection lens 150 (not shown). The light beam emitted from the exit surface 154 of the projection lens 150 is applied to the exposure substrate 156. The range of the arrow shown in FIG. 3A and FIG. 3B shows the exposure area A exposed by the light beam emitted from the light source 110.

  The table 177 of the Z-direction moving stage 176 is preferably processed flat, but depending on the size of the exposure substrate 156 placed on the table 177, the table 177 may have to be enlarged. In such a case, even if the flatness of the table 177 is improved, the table 177 may be curved, so-called swelled.

  Thus, when the table 177 of the Z-direction moving stage 176 is formed to be curved, when the exposure substrate 156 is placed on the table 177, the exposure substrate 156 is bent along the curved table 177. It will be. In this way, when the exposure substrate 156 is bent and placed on the table 177, the exposure area A of the exposure substrate 156 is horizontal as shown in FIGS. 3A and 3B. Thus, the table 177 is tilted with respect to the horizontal direction by controlling the tilt drive motor of the Z-direction moving stage 176 described above.

  The tilt drive motor may be controlled by either closed control or open control. In the closed control, a tilt amount measurement sensor (not shown) is provided on the Z-direction moving stage 176, and the tilt drive motor is controlled based on the tilt amount measured by the tilt amount measurement sensor. On the other hand, in the open control, the degree of bending generated in the table 177 of the Z-direction moving stage 176 is measured in advance, the result is stored, and the degree of bending stored at the time of exposure is stored. And the tilt drive motor is controlled to determine the tilt of the table 177.

  As described above, the table 177 for placing the exposure substrate 156 is formed on the upper surface of the Z direction moving stage 176, and the Z direction moving stage 176 is provided above the X direction moving stage 172. It has been. Therefore, by driving the X-direction moving stage 172 and the Y-direction moving stage 174 described above, the table 177 can be positioned at a desired X-direction position and Y-direction position.

<Abbe error generation>
As described above, the exposure area A to be exposed can be kept horizontal by tilting the Z-direction moving stage 176. However, when the Z-direction moving stage 176 is tilted, the Z-direction moving stage 176 is used. The distance (ΔZ shown in FIG. 3) between the horizontal reference position of the Z-direction moving stage 176 and the surface of the exposure substrate 156 changes according to the degree of inclination of the stage 176. For this reason, an Abbe error may occur depending on the distance ΔZ. If this Abbe error occurs, a horizontal position measurement error occurs.

  Further, depending on the size of the exposure substrate 156 placed on the table 177, the movement distance of the X-direction movement stage 172 and the Y-direction movement stage 174 described above may have to be increased. For this reason, it is necessary to increase the horizontal length of the linear guide 194 of the X-direction moving stage 172 and the linear guides 188a and 188b of the Y-direction moving stage 174, and the linear guide 194 and the linear guide 188a or 188b are required. In addition, bending in the Z direction is likely to occur. Even when the linear guide 194 or the linear guide 188a or 188b is bent in the Z direction, an Abbe error occurs depending on the degree of the Z direction curve, and a horizontal position measurement error occurs.

<< Exposure Substrates 156a and 156b >>
FIG. 4 is a view showing an example of the exposure substrates 156a and 156b. In the example shown in each of FIGS. 4A and 4B, the outer rectangle is a line indicating the outline of the outer shape of the exposure substrate 156a or 156b. In addition, each of a total of 12 squares (ER1 to ER12) of 4 in the horizontal direction and 3 in the vertical direction shown inside the outer rectangle represents one exposure area. The pattern formed on the reticle 142 is transferred to each of the 12 exposure regions ER1 to ER12. In addition, the square line which shows the outline of each of 12 exposure areas ER1-ER12 is for demonstrating an exposure area | region, and is a virtual line.

  When the exposure substrates 156a and 156b are placed on the table 177, as shown in FIGS. 4A and 4B, the vertical direction of the exposure substrates 156a and 156b depends on the X of the substrate placement stage 170. The horizontal direction of the exposure substrates 156a and 156b is set to the X direction of the substrate mounting stage 170 so that the direction is the same as the direction.

  Hereinafter, the exposure substrate 156a and the exposure substrate 156b are simply referred to as the exposure substrate 156 when it is not necessary to distinguish them.

  FIG. 4A shows an example of an exposure substrate 156a in which two reference marks are formed in each of the exposure regions, and FIG. 4B shows four reference marks formed in each of the exposure regions. An example of the exposure substrate 156b is shown.

  As described above, FIG. 4A shows the exposure substrate 156a in which the two reference marks RM1 and RM2 are formed in each of the 12 exposure regions (ER1 to ER12). In the example shown in FIG. 4A, the two reference marks RM1 and RM2 are in the vicinity of the midpoint of each of the opposite sides of the four sides of the square exposure region for each of the exposure regions ER1 to ER12. Is formed. The positions where the two reference marks RM1 and RM2 are formed are not limited to such positions, and the two reference marks RM1 and RM2 are formed so that the two reference marks RM1 and RM2 are separated as much as possible. Is good. By forming as far as possible, the accuracy of measuring the positions of the two reference marks RM1 and RM2 can be increased.

  In the example shown in FIG. 4A, one exposure substrate 156a has 12 exposure regions (ER1 to ER12), and two reference marks RM1 and RM2 are formed in each of them. A total of 24 reference marks are formed on one exposure substrate 156a.

  When the pattern formed on the reticle 142 is transferred to the exposure substrate 156a, a reticle on which two reticle reference marks are formed so as to correspond to the two reference marks RM1 and RM2 is used.

  As described above, FIG. 4B shows the exposure substrate 156b in which the four reference marks RM1 to RM4 are formed in each of the 12 exposure regions (ER1 to ER12). In the example shown in FIG. 4B, four reference marks RM1 to RM4 are formed in the vicinity of each of the four corners of the square exposure region for each of the exposure regions ER1 to ER12. The positions where the four reference marks RM1 to RM4 are formed are not limited to such positions, and may be formed so that the four reference marks RM1 to RM4 are separated as much as possible. By disposing them as far as possible, the accuracy of measuring the positions of the four reference marks RM1 to RM4 can be increased.

  In the example shown in FIG. 4B, one exposure substrate 156b has 12 exposure regions (ER1 to ER12), and four reference marks RM1 to RM4 are formed in each of them. A total of 48 reference marks are formed on one exposure substrate 156b.

  When the pattern formed on the reticle 142 is transferred to the exposure substrate 156b, a reticle on which four reticle reference marks are formed so as to correspond to each of the four reference marks RM1 to RM4 is used.

<Displacement of fiducial mark position>
The reference marks RM1 and RM2 formed on the exposure substrate 156a and the reference marks RM1 to RM4 formed on the exposure substrate 156b are originally formed so as to be located at desired positions. However, these reference marks are formed by melting the surface of the exposure substrate 156 with laser light, or formed by mechanical processing with a drill or the like. Depending on the accuracy of the method of forming such a reference mark, the reference mark may be formed at a position displaced from the originally designed position.

  In addition, heat may be applied to the exposure substrate 156, or force may be applied to the exposure substrate 156 in the middle of conveyance, so that the exposure substrate 156 may be entirely or partially deformed. In such a case, the reference mark is positioned at a position different from the originally designed position.

  Further, as described above, an Abbe error may occur depending on the structure of the X-direction moving stage 172, the Y-direction moving stage 174, and the Z-direction moving stage 176.

  As described above, in order to accurately transfer the pattern formed on the reticle 142 to the exposure substrate 156 when the reference mark is displaced from the originally designed position or when an Abbe error occurs. Therefore, when positioning the X-direction moving stage 172, the Y-direction moving stage 174, and the Z-direction moving stage 176, it is necessary to consider the reference mark error. This positioning will be described later.

  In the present specification, the fact that the reference mark is positioned at a position displaced from the originally designed position is also referred to as an error in the position of the reference mark.

<<< Procedure for Transfer of Pattern Formed on Reticle 142 >>>
As described above, the pattern formed on the reticle 142 is transferred to the exposure substrate 156 by the exposure light emitted from the light source 110. In the present embodiment, exposure substrate 156 has a plurality of exposure regions, and a pattern formed on reticle 142 is sequentially transferred to each of the plurality of exposure regions.

  As a preparation for transferring the pattern formed on the reticle 142, as described above, the position of the image of the reticle reference mark and the position of the table reference mark 179 must be matched. A table reference mark 179 for aligning with the reticle reference mark formed on the reticle 142 is formed on a part of the upper surface of the table 177. The X-direction moving stage 172 and the Y-direction moving stage 174 are driven to move the table 177 so that the position of the reticle reference mark image matches the position of the table reference mark 179. The table reference mark 179 when the position of the image of the reticle reference mark matches the position of the table reference mark 179 is photographed by the alignment optical system 160, and the position of the table reference mark 179 is stored.

  When the pattern formed on the reticle 142 is transferred to the exposure substrate 156, first, the position of the reference mark in the desired exposure area is matched with the position of the table reference mark 179 stored in the above preparation. The X direction moving stage 172 and the Y direction moving stage 174 are moved.

  For example, when the pattern formed on the reticle 142 is transferred to the exposure region ER1 of the exposure substrate 156a shown in FIG. 4A, the positions of the reference marks RM1 and RM2 formed in the exposure region ER1 are the above-described processing. The X-direction movement stage 172 and the Y-direction movement stage 174 are moved so as to coincide with the stored position of the table reference mark 179. As described above, when a pattern is transferred to the exposure substrate 156a, a reticle on which two reticle reference marks are formed is used as the reticle 142 so as to correspond to each of the two reference marks RM1 and RM2.

  Similarly, for example, when the pattern formed on the reticle 142 is transferred to the exposure region ER6 of the exposure substrate 156b shown in FIG. 4B, the positions of the reference marks RM1 to RM4 formed in the exposure region ER6 are the same. The X-direction moving stage 172 and the Y-direction moving stage 174 are moved so as to coincide with the position of the table reference mark 179 stored in the above-described processing. Also in this case, as described above, when a pattern is transferred to the exposure substrate 156b, a reticle on which four reticle reference marks are formed is used as the reticle 142 so as to correspond to each of the four reference marks RM1 to RM4. .

  The X-direction moving stage 172 and the Y-direction moving stage 174 are moved so that the position of the reference mark in the desired exposure area matches the position of the stored table reference mark 179, and at that position. Then, exposure light is emitted from the light source 110 to transfer the pattern formed on the reticle 142 to the exposure substrate 156.

  In this manner, the procedure of emitting exposure light from the light source 110 is performed by matching the position of the reference mark in the desired exposure area with the position of the stored table reference mark 179, thereby forming the reticle 142 on the reticle 142. The pattern can be sequentially transferred to each of the plurality of exposure areas.

  However, when an error occurs in the position of the reference mark described above, it is necessary to position the X-direction moving stage 172 and the Y-direction moving stage 174 according to the generated error.

<<< Alignment method >>>
As a method of positioning the X direction moving stage 172 and the Y direction moving stage 174 in accordance with an error, there are a die-by-die method and a global method. In the die-by-die method, an error in the position of the reference mark is calculated for each of a plurality of exposure areas, and the positions of the X direction moving stage 172 and the Y direction moving stage 174 are corrected and positioned in accordance with the error. The pattern formed on the reticle 142 is transferred to the exposure substrate 156. On the other hand, in the global method, errors over the entire exposure substrate 156 are calculated in advance. First, an error over the entire exposure substrate 156 is calculated, and the position where the X direction moving stage 172 and the Y direction moving stage 174 are positioned is corrected based on the measured error, and the corrected position is stored. . When the pattern formed on the reticle 142 is transferred to the exposure substrate 156, the X-direction movement stage 172 and the Y-direction movement stage 174 are positioned at the corrected positions, and the pattern is sequentially transferred to the exposure substrate 156.

<< Die-by-die method >>
In the die-by-die method, as described above, the position of the reference mark is measured by the alignment optical system 160 described above for each of a plurality of exposure regions of the exposure substrate 156, and the position of the substrate placement stage 170 is corrected according to the measurement result. Then, the pattern formed on the reticle 142 is transferred to the exposure substrate 156.

  As described above, in this die-by-die method, the position of the reference mark is measured by the alignment optical system 160, the position of the substrate mounting stage 170 is corrected according to the measurement result, and whether or not the position is appropriate is determined. Check. Since the substrate mounting stage 170 can be accurately positioned without using an interferometer for determining the position of the X direction moving stage 172 and the position of the Y direction moving stage 174, the projection exposure apparatus 100 can be made inexpensive. be able to.

The die-by-die method will be further described in detail.
In the first to third aspects of the procedure by the die-by-die method described below, the above-described preparation is performed, and the position of the image of the reticle reference mark and the position of the table reference mark 179 are matched. It is assumed that the position of the table reference mark 179 is stored in advance.

<First aspect of procedure by die-by-die method>
This first mode is for transferring the pattern formed on the reticle 142 to each of the 12 exposure regions ER1 to ER12 of the exposure substrate 156a. As described above, two reference marks RM1 and RM2 are formed in each of the 12 exposure regions ER1 to ER12 of the exposure substrate 156a. In the first aspect, the alignment optical system 160 is used to determine the positions of the two reference marks RM1 and RM2. As described above, the alignment optical system 160 includes the two microscopes 162a and 162b. The microscope 162a detects the reference mark RM1 on the exposure substrate 156a, and the microscope 162b detects the reference mark RM2 on the exposure substrate 156a.

  Each of the two microscopes 162a and 162b includes an image sensor (not shown) such as a CCD camera. The surface of the exposure substrate 156a including the reference mark RM1 or RM2 is photographed by the image sensor, and a reference is obtained from the photographed images. The position of the reference mark RM1 or RM2 is determined by extracting the image of the mark RM1 or RM2.

  FIG. 5A to FIG. 5C are diagrams showing procedures for detecting the position of the reference mark, adjusting the position of the exposure substrate 156a, and exposing the exposure substrate 156a according to the first aspect. In the example shown in FIGS. 5A to 5C, ER1 is representatively shown among the 12 exposure regions ER1 to ER12 of the exposure substrate 156a. In the example shown in FIGS. 5A to 5C, the upward direction in the drawing is the + X direction, and the left direction in the drawing is the + Y direction. Further, in the example shown in FIGS. 5A to 5C, a large circle indicates an irradiable range EA in which the light beam emitted from the projection lens 150 can be irradiated.

  FIG. 5A shows that the exposure region ER1 of the exposure substrate 156a placed on the table 177 is irradiated by driving the X-direction movement stage 172 and the Y-direction movement stage 174 of the substrate placement stage 170. The state when positioned in the possible range EA is shown. The design positions of the two reference marks RM1 and RM2 formed in each of the exposure regions ER1 to ER12 of the exposure substrate 156a are stored in advance, and based on this value, the X-direction moving stage 172 is stored. And the Y-direction moving stage 174 can move the exposure regions ER1 to ER12 of the exposure substrate 156a within the irradiable range EA.

  In the state of FIG. 5A, the alignment optical system 160 is located at the retracted position. As shown in FIG. 1, the retracted position of the alignment optical system 160 is set so that the alignment optical system 160 does not obstruct exposure to the exposure substrate 156a or various operations. Is retracted from below the projection lens 150. For example, the retracted position of the alignment optical system 160 is a position where the alignment optical system 160 is positioned when exposure light is emitted from the light source 110 and the pattern formed on the reticle 142 is transferred to the exposure substrate 156a. The retracted position of the alignment optical system 160 is preferably the home position of the alignment optical system 160. For simplicity, FIG. 5A shows a state in which the alignment optical system 160 is positioned at a position retracted from the exposure region ER1, but as described above, this position is actually This is the position where the alignment optical system 160 is retracted from the substrate mounting stage 170.

  The alignment optical system 160 includes an X-direction alignment moving stage (not shown). By driving the X-direction alignment moving stage, the alignment optical system 160 can be moved in the ± X directions as indicated by the white arrows AX1 or AX2 in FIG. 5A or 5C. .

  FIG. 5B shows a state when the alignment optical system 160 is moved to the measurement position. As described above, the alignment optical system 160 includes the X-direction alignment movement stage, and by driving the X-direction alignment movement stage, as shown by the white arrow AX1 in FIG. The optical system 160 can be moved in the + X direction to be positioned at the measurement position.

  This measurement position is a position where the alignment optical system 160 is positioned when the reference mark RM1 is photographed with the microscope 162a and the reference mark RM2 is photographed with the microscope 162b. It is only necessary to ensure that the measurement position of the alignment optical system 160 is a fixed position, and it is not necessary to determine the position of the alignment optical system 160 when positioned at the measurement position using a position detection device. That is, it is only necessary that when the alignment optical system 160 is positioned at the measurement position where the reference marks RM1 and RM2 can be photographed from the retraction position described above, the measurement position is always a constant position.

  The alignment optical system 160 may be moved from the retracted position to the measuring position as follows. First, for example, when the retracted position of the alignment optical system 160 described above is the home position of the X-direction alignment moving stage, the number of pulse signals corresponding to the distance from the retracted position to the measurement position is set as the X-direction alignment. It is stored in advance in a control means for controlling the motor of the moving stage. Next, when positioning the alignment optical system 160 from the retracted position to the measurement position, the number of stored pulse signals is supplied from the control means to the motor so that the alignment optical system 160 is moved from the home position of the X-direction alignment moving stage. The alignment optical system 160 can always be positioned at a certain measurement position.

  As shown in FIG. 5B, the alignment optical system 160 is moved to the measurement position, and the reference mark RM1 is photographed with the microscope 162a, and the reference mark RM2 is photographed with the microscope 162b. The captured image is stored in an image storage means (not shown), and image processing is performed by an image processing means (not shown) to extract images of the reference marks RM1 and RM2, and the position of the reference mark RM1 and the reference mark The position of RM2 is calculated. Note that the position of the reference mark RM1 and the position of the reference mark RM2 at this time are positions on the image, and may be any position, for example, in units of pixels (pixels). The position does not have to be the unit of length used.

  The position of the reference mark RM1 and the position of the reference mark RM2 obtained in this way are a position in the X direction (X coordinate) and a position in the Y direction (Y coordinate). By obtaining the X coordinate and Y coordinate of the reference mark RM1 and the X coordinate and Y coordinate of the reference mark RM2, as will be described later, the X offset, Y offset, rotation, and X direction of the exposure region ER1 are described. Four pieces of information such as magnification are obtained. Note that these four pieces of information will be described later.

  It is determined whether or not the position of the obtained reference mark RM1 and the position of the reference mark RM2 match the position of the table reference mark 179 stored in advance by preparation. As described above, the position of the table reference mark 179 stored in advance is the position of the image of the reticle reference mark formed on the reticle 142. When it is determined that the position of the reference mark RM1 and the position of the reference mark RM2 do not match the position of the table reference mark 179 stored in advance, the position of the reference mark RM1 and the position of the reference mark RM2 are determined in advance. The X-direction movement stage 172 and the Y-direction movement stage 174 of the substrate placement stage 170 are driven so as to coincide with the stored position of the table reference mark 179 to position the exposure region ER1 of the exposure substrate 156a. . In this way, the exposure region ER1 of the exposure substrate 156a can be positioned so that the position of the reference mark RM1 and the position of the reference mark RM2 correspond to the position of the reference mark formed on the reticle 142. In addition, when the magnification in the X direction obtained from the position of the reference mark RM1 and the position of the reference mark RM2 is not 1, control for changing the magnification of the projection lens 150 is also performed so that the magnification in the X direction becomes 1. Do it at the same time.

  FIG. 5C shows a state when the alignment optical system 160 is moved again to the retracted position. By driving the X-direction alignment moving stage described above, the alignment optical system 160 can be moved in the −X direction and positioned at the retracted position, as indicated by the white arrow AX2 in FIG. . The retracted position is the same as that described above, and the alignment optical system 160 is placed on the projection lens 150 so that the alignment optical system 160 does not obstruct exposure to the exposure substrate 156a or various operations. This is the position retracted from below.

  After the alignment optical system 160 is retracted from below the projection lens 150 in this way, exposure light is emitted from the light source 110, and the pattern formed on the reticle 142 is transferred to the exposure region ER1.

Next, by driving the X-direction movement stage 172 and the Y-direction movement stage 174 of the substrate placement stage 170, the exposure area ER2 of the exposure substrate 156a placed on the table 177 is brought into the irradiable range EA. In the same manner as in the state shown in FIG. 5A, the above-described procedure is performed to transfer the pattern formed on the reticle 142 to the exposure region ER2. In this manner, the pattern formed on the reticle 142 can be sequentially transferred for all the 12 exposure regions ER1 to ER12.
<Second aspect of procedure by die-by-die method>
In the second mode, the pattern formed on the reticle 142 is transferred to each of the 12 exposure regions ER1 to ER12 of the exposure substrate 156b described above. As described above, four reference marks RM1 to RM4 are formed in each of the 12 exposure regions ER1 to ER12 of the exposure substrate 156a. In the second mode, the alignment optical system 160 is used to determine the positions of the four reference marks RM1 to RM4. The alignment optical system 160 in the second aspect includes two microscopes 162a and 162b as in the first aspect. The microscope 162a detects the reference mark RM1 or RM3 on the exposure substrate 156b, and the microscope 162b detects the reference mark RM2 or RM4 on the exposure substrate 156b. Since the configuration and function of the alignment optical system 160 are the same as those in the first mode, description thereof is omitted in the second mode.

  Each of the two microscopes 162a and 162b includes an image sensor (not shown) such as a CCD camera, and the surface of the exposure substrate 156b including the reference marks RM1 to RM4 is photographed by the image sensor, and a reference is obtained from the photographed images. The positions of the reference marks RM1 to RM4 are determined by extracting the images of the marks RM1 to RM4.

  FIG. 6A to FIG. 6D are diagrams showing procedures for detecting the position of the reference mark, adjusting the position of the exposure substrate 156a, and exposing the exposure substrate 156a according to the second mode. In the example shown in FIGS. 6A to 6D, ER1 is representatively shown among the 12 exposure regions ER1 to ER12 of the exposure substrate 156b. In the example shown in FIGS. 6A to 6D, the upward direction in the drawing is the + X direction, and the left direction in the drawing is the + Y direction. Furthermore, in the examples shown in FIGS. 6A to 6D, a large circle indicates the irradiable range EA in which the light beam emitted from the projection lens 150 can be irradiated.

  FIG. 6A shows that the exposure region ER1 of the exposure substrate 156b placed on the table 177 is irradiated by driving the X-direction movement stage 172 and the Y-direction movement stage 174 of the substrate placement stage 170. The state when positioned in the possible range EA is shown. As in the first mode, the design positions of the four reference marks RM1 to RM4 formed in each of the exposure regions ER1 to ER12 of the exposure substrate 156b are stored in advance, and based on this value. Thus, by moving the X-direction moving stage 172 and the Y-direction moving stage 174, the exposure regions ER1 to ER12 of the exposure substrate 156b can be positioned in the irradiable range EA.

  In the state of FIG. 6A, the alignment optical system 160 is located at the retracted position. This retracted position is also the same as in the first mode.

  FIG. 6B shows a state when the alignment optical system 160 is moved to the measurement position and the exposure substrate 156b is moved to the advanced position.

  As in the first embodiment, the alignment optical system 160 includes an X-direction alignment movement stage, and as shown by a white arrow AX1 in FIG. 6A by driving the X-direction alignment movement stage. Further, the alignment optical system 160 can be moved in the + X direction to be positioned at the measurement position. Although this measurement position is different from that of the first mode (see FIG. 5B), the reference mark RM1 or RM3 can be photographed with the microscope 162a, and the reference mark RM2 or RM4 can be photographed with the microscope 162b. It is only necessary to ensure that the position is constant.

  On the other hand, by driving the X-direction moving stage 172 described above, the X-direction moving stage 172 is moved in the −X direction as shown by the black arrow AX3 in FIG. Can be positioned. The original position of the X-direction moving stage 172 is the position shown in FIG. 6 (a), FIG. 6 (c), or FIG. 6 (d). The movement from the original position to the advance position may be performed as follows. First, the number of pulse signals corresponding to the distance from the original position of the X-direction moving stage 172 to the advanced position is stored in advance in a control means for controlling the motor of the X-direction moving stage 172. Next, when the X-direction moving stage 172 is positioned from the original position to the advanced position, by supplying the pulse signals from the control means to the motor by the number of stored pulse signals, the X-direction moving stage 172 The X-direction moving stage 172 can be positioned from the original position to the advanced position.

  By moving the alignment optical system 160 to the measurement position and moving the X-direction moving stage 172 to the advanced position, as shown in FIG. 6B, the entire reference mark RM1 is within the imaging region of the microscope 162a. The alignment optical system 160 and the X-direction moving stage 172 are positioned so that the entire reference mark RM2 is included in the imaging region of the microscope 162b.

  As shown in FIG. 6B, the alignment optical system 160 is positioned at the measurement position, the X-direction moving stage 172 is positioned at the advanced position, the reference mark RM1 is photographed with the microscope 162a, and the reference mark RM2 is captured with the microscope 162b. Shoot. The captured image is subjected to image processing by an image storage means (not shown), the images of the reference marks RM1 and RM2 are extracted, and the position of the reference mark RM1 and the position of the reference mark RM2 are calculated. Note that the position of the reference mark RM1 and the position of the reference mark RM2 at this time are positions on the image, and may be any position, for example, in units of pixels (pixels). The position does not have to be the unit of length used.

  In FIG. 6C, the alignment optical system 160 remains positioned at the measurement position, and the X-direction moving stage 172 is moved in the + X direction as indicated by the black arrow in FIG. Return to position. By positioning the alignment optical system 160 at the measurement position and the X-direction moving stage 172 at the original position, the reference mark RM3 can be photographed with the microscope 162a, and the reference mark RM4 can be photographed with the microscope 162b. Also in this case, the captured image is stored in an image storage means (not shown), and image processing is performed by an image processing means (not shown) to extract images of the reference marks RM3 and RM4. The position and the position of the reference mark RM4 are calculated. Note that the position of the reference mark RM3 and the position of the reference mark RM4 at this time are also positions on the image, and may be any position, for example, in units of pixels (pixels). The position does not have to be in the unit of length to be generated.

  The positions of the four reference marks RM1 to RM4 thus obtained are a position in the X direction (X coordinate) and a position in the Y direction (Y coordinate). By obtaining the positions of these reference marks RM1 to RM4, it is possible to obtain five pieces of information including the X offset, the Y offset, the rotation, the magnification in the X direction, and the magnification in the Y direction of the exposure region ER1. Note that these five pieces of information will be described later.

  It is determined whether or not the positions of the obtained reference marks RM1 to RM4 coincide with the position of the table reference mark 179 stored in advance by preparation. The position of the table reference mark 179 stored in advance is the position of the image of the reticle reference mark formed on the reticle 142. When it is determined that the positions of the reference marks RM1 to RM4 do not coincide with the positions of the table reference marks 179 stored in advance, the positions of the reference marks RM1 to RM4 are the positions of the table reference marks 179 stored in advance. The X direction moving stage 172 and the Y direction moving stage 174 of the substrate mounting stage 170 are driven so as to coincide with the position, and the exposure region ER1 of the exposure substrate 156b is positioned. In this way, the exposure region ER1 of the exposure substrate 156a can be positioned so that the positions of the reference marks RM1 to RM4 correspond to the positions of the reference marks formed on the reticle 142. Note that when the magnification in the X direction and the magnification in the Y direction obtained from the positions of the reference marks RM1 to RM4 are not 1, the magnification of the projection lens 150 is set so that the magnification in the X direction and the magnification in the Y direction are 1. At the same time, control to change

  FIG. 6D shows a state when the alignment optical system 160 is moved again to the retracted position. By driving the X-direction alignment moving stage described above, the alignment optical system 160 can be moved in the −X direction and positioned at the retracted position, as indicated by the white arrow AX2 in FIG. . This retracted position is the same as that described above, and the alignment optical system 160 is placed on the projection lens 150 so that the alignment optical system 160 does not obstruct exposure to the exposure substrate 156 or various operations. This is the position to be retracted from below.

  After the alignment optical system 160 is retracted from below the projection lens 150 in this way, exposure light is emitted from the light source 110, and the pattern formed on the reticle 142 is transferred to the exposure region ER1.

  Next, by driving the X-direction movement stage 172 and the Y-direction movement stage 174 of the substrate placement stage 170, the exposure area ER2 of the exposure substrate 156b placed on the table 177 is brought into the irradiable range EA. Positioning is performed in the state shown in FIG. 6A, the above-described procedure is performed, and the pattern formed on the reticle 142 is transferred to the exposure region ER1. In this manner, the pattern formed on the reticle 142 can be sequentially transferred for all the 12 exposure regions ER1 to ER12.

<Third aspect of procedure by die-by-die method>
In the third aspect, the pattern formed on the reticle 142 is transferred to each of the 12 exposure regions ER1 to ER12 of the exposure substrate 156b described above. As described above, four reference marks RM1 to RM4 are formed in each of the 12 exposure regions ER1 to ER12 of the exposure substrate 156a. In the third aspect, two alignment optical systems 160a and 160b are used. The reference mark RM1 is detected by the microscope 162aa, the reference mark RM2 is detected by the microscope 162ab, the reference mark RM3 is detected by the microscope 162ba, and the reference mark RM4 is detected by the microscope 162bb. Since the configuration and functions of the alignment optical systems 160a and 160b are the same as those of the alignment optical system 160 of the first aspect and the second aspect, description thereof is omitted in the third aspect.

  Each of the four microscopes 162aa and 162ab and 162ba and 162bb includes an image sensor (not shown) such as a CCD camera, and images the surface of the exposure substrate 156b including the reference marks RM1 to RM4 with the image sensor. The positions of the reference marks RM1 to RM4 are determined by extracting images of the reference marks RM1 to RM4 from the captured image.

  FIG. 7A to FIG. 7C are diagrams showing a procedure for detecting the position of the reference mark, adjusting the position of the exposure substrate 156a, and exposing the exposure substrate 156a according to the third aspect. In the example shown in FIGS. 7A to 7C, ER1 is representatively shown among the 12 exposure regions ER1 to ER12 of the exposure substrate 156b. In the example shown in FIGS. 7A to 7C, the upward direction in the drawing is the + X direction, and the left direction in the drawing is the + Y direction. Further, in the examples shown in FIGS. 7A to 7C, a large circle indicates the irradiable range EA in which the light beam emitted from the projection lens 150 can be irradiated.

  FIG. 7A illustrates an irradiation area ER1 of the exposure substrate 156b placed on the table 177 by driving the X-direction movement stage 172 and the Y-direction movement stage 174 of the substrate placement stage 170. The state when positioned in the possible range EA is shown. The design positions of the four reference marks RM1 to RM4 formed in the exposure regions ER1 to ER12 of the exposure substrate 156b are stored in advance, and the X-direction moving stage 172 is based on this value. And the Y-direction moving stage 174 can move the exposure regions ER1 to ER12 of the exposure substrate 156b within the irradiable range EA.

  In the state of FIG. 7A, the alignment optical systems 160a and 160b are located at the retracted position. This retracted position is also the same as in the first and second aspects.

  FIG. 7B shows a state when both the alignment optical systems 160a and 160b are moved to the measurement position. Each of alignment optical systems 160a and 160b includes an X-direction alignment moving stage. By driving the X-direction alignment moving stage of the alignment optical system 160a, the alignment optical system 160a is moved in the -X direction and positioned at the measurement position as indicated by the white arrow AX5 in FIG. In addition, as shown by a white arrow AX6 in FIG. 7A, the alignment optical system 160b can be moved in the + X direction to be positioned at the measurement position.

  By moving both the alignment optical systems 160a and 160b to the measurement position, as shown in FIG. 7B, the entire reference mark RM1 is included in the imaging region of the microscope 162aa, and the entire reference mark RM2 is included. Are included in the imaging area of the microscope 162ab, the entire reference mark RM3 is included in the imaging area of the microscope 162ba, and the entire reference mark RM4 is included in the imaging area of the microscope 162bb. Both systems 160a and 160b are located.

  As shown in FIG. 7B, the alignment optical system 160a is moved to the measurement position, and the reference mark RM1 is photographed with the microscope 162aa, and the reference mark RM2 is photographed with the microscope 162ab. Similarly, the alignment optical system 160b is positioned at the measurement position, the reference mark RM3 is photographed with the microscope 162ba, and the reference mark RM4 is photographed with the microscope 162bb. The photographed image is stored in an image storage means (not shown), image processing is performed by an image processing means (not shown), images of reference marks RM1 to RM4 are extracted, and the position of the reference mark RM1 and the reference mark The position of RM2, the position of the reference mark RM3, and the position of the reference mark RM4 are calculated. Note that the positions of these reference marks RM1 to RM4 at this time are positions on the image, and may be positions that have, for example, a pixel (pixel) or the like as a unit, and are generally used lengths such as millimeters. The position does not have to be a unit using the unit of height.

  The positions of the four reference marks RM1 to RM4 thus obtained are a position in the X direction (X coordinate) and a position in the Y direction (Y coordinate). Also according to the third aspect, by obtaining the positions of these reference marks RM1 to RM4, five of the X offset, the Y offset, the rotation, the X direction magnification, and the Y direction magnification of the exposure region ER1 are obtained. Information can be obtained. Note that these five pieces of information will be described later.

  It is determined whether or not the positions of the obtained reference marks RM1 to RM4 coincide with the position of the table reference mark 179 stored in advance by preparation. As described above, the position of the table reference mark 179 stored in advance is the position of the image of the reticle reference mark formed on the reticle 142. When it is determined that the positions of the reference marks RM1 to RM4 do not coincide with the positions of the table reference marks 179 stored in advance, the positions of the reference marks RM1 to RM4 are the positions of the table reference marks 179 stored in advance. The X direction moving stage 172 and the Y direction moving stage 174 of the substrate mounting stage 170 are driven so as to coincide with the position, and the exposure region ER1 of the exposure substrate 156b is positioned. In this way, the exposure region ER1 of the exposure substrate 156a can be positioned so that the positions of the reference marks RM1 to RM4 correspond to the positions of the reference marks formed on the reticle 142. Note that when the magnification in the X direction and the magnification in the Y direction obtained from the positions of the reference marks RM1 to RM4 are not 1, the magnification of the projection lens 150 is set so that the magnification in the X direction and the magnification in the Y direction are 1. At the same time, control to change

  FIG. 7C shows a state when the alignment optical systems 160a and 160b are moved again to the retracted position. By driving the X-direction alignment moving stage of the alignment optical system 160a, the alignment optical system 160a is moved in the + X direction and positioned at the retracted position as indicated by the white arrow AX7 in FIG. Can do. Similarly, by driving the X-direction alignment moving stage of the alignment optical system 160b, the alignment optical system 160b is moved in the −X direction as shown by the white arrow AX8 in FIG. Can be positioned. The retracted position is the same as that described above, and the alignment optical systems 160a and 160b are installed in order to prevent the alignment optical systems 160a and 160b from obstructing the exposure of the exposure substrate 156 and various operations. This is the position where the projection lens 150 is retracted from below.

  After the alignment optical system 160 is retracted from below the projection lens 150 in this way, exposure light is emitted from the light source 110, and the pattern formed on the reticle 142 is transferred to the exposure region ER1.

  Next, by driving the X-direction movement stage 172 and the Y-direction movement stage 174 of the substrate placement stage 170, the exposure area ER2 of the exposure substrate 156b placed on the table 177 is brought into the irradiable range EA. Positioning is performed in the state shown in FIG. 7A, the above-described procedure is performed, and the pattern formed on the reticle 142 is transferred to the exposure region ER1. In this manner, the pattern formed on the reticle 142 can be sequentially transferred for all the 12 exposure regions ER1 to ER12.

  In the third aspect, since the positions of the four reference marks RM1 to RM4 can be detected at the same time for each of the exposure regions, the detection process can be rapidly advanced.

  In the second aspect and the third aspect described above, information about both the X direction magnification error and the Y direction magnification error can be obtained for each exposure region. This is effective when the direction magnification error occurs separately.

<< Global method >>
As described above, in the global method, an error over the entire exposure substrate 156 is calculated in advance, and the position where the X direction moving stage 172 and the Y direction moving stage 174 are positioned is corrected in advance based on the measured error. By storing the corrected position, when the pattern formed on the reticle 142 is transferred to the exposure substrate 156, the X-direction moving stage 172 and the Y-direction moving stage 174 are positioned at the corrected positions. Then, the pattern is sequentially transferred to the exposure substrate 156.

<Exposed substrate 156c>
FIG. 8 shows an example of the exposure substrate 156c used in the case of the global method. In the exposure substrate 156c shown in FIG. 8, as with the exposure substrates 156a and 156b described above, the outer rectangle is a line indicating the outline of the outer shape of the exposure substrate 156c. In addition, each of a total of 12 squares (ER1 to ER12) of 4 in the horizontal direction and 3 in the vertical direction shown inside the outer rectangle represents one exposure area. The pattern formed on the reticle 142 is transferred to each of the 12 exposure regions ER1 to ER12. In addition, the square line which shows the outline of each of 12 exposure areas ER1-ER12 is for demonstrating an exposure area | region, and is a virtual line.

  When the exposure substrate 156c is placed on the table 177, the horizontal direction of the exposure substrate 156c is set so that the vertical direction of the exposure substrate 156c is the X direction of the substrate placement stage 170, as shown in FIG. The substrate mounting stage 170 is set in the X direction.

  In the exposure substrate 156c shown in FIG. 8, two reference marks RM1 and RM2 are formed in each of the four exposure regions ER1, ER4, ER9, and ER12. These four exposure areas ER1, ER4, ER9 and ER12 are exposure areas closest to the four corners of the exposure substrate 156c. When the exposure substrate 156c shown in FIG. 8 is used, the positions of the two reference marks RM1 and RM2 are determined using the alignment optical system 160 described above. The alignment optical system 160 includes two microscopes 162a and 162b. The microscope 162a detects the reference mark RM1 on the exposure substrate 156a, and the microscope 162b detects the reference mark RM2 on the exposure substrate 156a. Since the configuration and function of the alignment optical system 160 are the same as those in the first mode of the procedure by the die-by-die method, the description is omitted here.

  When the pattern formed on the reticle 142 is transferred to the exposure substrate 156c, a reticle on which two reticle reference marks are formed so as to correspond to each of the two reference marks RM1 and RM2 is used as the reticle 142.

  Further, even in the procedure based on the global method described below, the position of the table reference mark 179 when the above-described preparation is performed and the position of the image of the reticle reference mark is matched with the position of the table reference mark 179 is Assume that it is stored in advance.

  Further, the design position (Xmark_des1 (n), Ymark_des1 (n)) of the reference mark RM1 formed in each of the four exposure regions ER1, ER4, ER9, and ER12 of the exposure substrate 156c and the design of the reference mark RM2 Positions (Xmark_des2 (n), Ymark_des2 (n)) are stored in advance, and the exposure substrate 156c is moved by moving the X-direction moving stage 172 and the Y-direction moving stage 174 based on these values. These four exposure areas ER1, ER4, ER9 and ER12 can be positioned in the irradiable range EA. The variable n will be described later.

<Detection of positions of reference marks RM1 and RM2>
FIG. 9 is a flowchart showing a procedure of global processing using the exposure substrate 156c. Below, it demonstrates using the flowchart of this FIG. Note that the variable n shown in the flowchart of FIG. 9 indicates the above-described four exposure regions ER1, ER4, ER9, and ER12. n = 1 indicates that the exposure area is ER1, and the exposure area ER1 is referred to as a first measurement exposure area. n = 2 indicates that the exposure area is ER4, and the exposure area ER4 is referred to as a second measurement exposure area. n = 3 indicates that the exposure region is ER12, and the exposure region ER12 is referred to as a third measurement exposure region. n = 4 indicates that the exposure area is ER9, and the exposure area ER9 is referred to as a fourth measurement exposure area.

  First, the alignment optical system 160 is moved from the retracted position to the measurement position (step S11). The retraction position and measurement position of the alignment optical system 160 are the same positions as those of the die-by-die system. The retracted position is preferably the home position of the alignment optical system 160. The measurement position may be any position that can ensure that the reference mark RM1 can be photographed with the microscope 162a and the reference mark RM2 can be photographed with the microscope 162b.

  Next, in order to position the exposure area ER1 of the exposure substrate 156c placed on the table 177 as the first measurement exposure area (n = 1) in the irradiable range EA, the X direction of the substrate placement stage 170 The moving stage 172 and the Y direction moving stage 174 are driven to move the table 177 (step S12). As described above, the design position (Xmark_des1 (n), Ymark_des1 (n)) of the reference mark RM1 formed in each of the four exposure regions ER1, ER4, ER9, and ER12 and the design of the reference mark RM2. Since the position (Xmark_des2 (n), Ymark_des2 (n)) is stored in advance, the process of step S12 can be performed based on the stored design position.

  By performing the processes in steps S11 and S12 described above, the state similar to that in FIG.

  Next, the reference mark RM1 is photographed with the microscope 162a of the alignment optical system 160, and the reference mark RM2 is photographed with the microscope 162b (step S13). In this way, the reference marks RM1 and RM2 in the exposure area ER1 (first measurement exposure area (n = 1)) can be photographed.

  Next, the photographed image is stored in an image storage means (not shown), image processing is performed by an image processing means (not shown), images of the reference marks RM1 and RM2 are extracted, and the position of the reference mark RM1 ( Xmark_1 (1), Ymark_1 (1)) and the position of the reference mark RM2 (Xmark_2 (1), Ymark_2 (1)) are calculated and stored as the position of the reference mark RM1 and the position of the reference mark RM2 in the exposure area ER1. It is stored in means (not shown) (step S14). At this time, the position of the reference mark RM1 (Xmark_1 (1), Ymark_1 (1)) and the position of the reference mark RM2 (Xmark_2 (1), Ymark_2 (1)) are also positions on the image in the same manner as in the diby-die method. For example, the position may be a position using a pixel (pixel) or the like as a unit, and does not need to be a position using a commonly used length unit such as a millimeter. The position of the reference mark RM1 (Xmark_1 (1), Ymark_1 (1)) and the position of the reference mark RM2 (Xmark_2 (1), Ymark_2 (1)) in the exposure area ER1 obtained in this way is a position in the X direction. (X coordinate) and position in the Y direction (Y coordinate).

  By executing the processes of steps S12 to S14 described above, the positions of the reference marks RM1 (Xmark_1 (1), Ymark_1 (1)) and RM2 in the exposure area ER1 (first measurement exposure area (n = 1)). (Xmark_2 (1), Ymark_2 (1)) can be detected and the position can be stored.

  Next, it is determined whether the two reference marks RM1 and RM2 in all the measurement exposure areas (ER1, ER4, ER9, and ER12) have been processed (step S15). When it is determined that the processing is not performed, the processing in the above-described steps S12 to S14 is performed again in order to perform processing in the next measurement exposure region (step S16). Thus, when n = 2, the position of the reference mark RM1 (Xmark_1 (2), Ymark_1 (2)) and the position of the reference mark RM2 (Xmark_2 (2), Ymark_2 (2)) in the exposure region ER4. Is detected and stored, and when n = 3, the position of the reference mark RM1 (Xmark_1 (3), Ymark_1 (3)) and the reference mark RM2 (Xmark_2 (3), Ymark_2 (3) in the exposure region ER12 )) Is determined and stored, and when n = 4, the position of the reference mark RM1 (Xmark_1 (4), Ymark_1 (4)) and the reference mark RM2 (Xmark_2 (4)) in the exposure region ER9. , Ymark_2 (4)) can be determined and stored.

  If it is determined in step S15 that all the measurement exposure areas (ER1, ER4, ER9, and ER12) have been processed, the alignment optical system 160 is moved from the measurement position to the retracted position (step S17).

  By executing the processing described above, the positions of the reference marks RM1 (Xmark_1 (n), Ymark_1 (n)) in the four exposure regions ER1, ER4, ER9, and ER12 and the positions of the reference marks RM2 (Xmark_2 (n), Ymark_2 (n)) and the position can be stored. As described above, in step S11, after the alignment optical system 160 is positioned from the retracted position to the measurement position, the alignment optical system 160 is maintained in the measurement position until all the exposure regions are processed. When the nth exposure area is positioned in the irradiable range EA in step S12, the state is the same as in FIG. 5B, and the reference mark RM1 is immediately photographed with the microscope 162a, and the reference mark RM2 is captured with the microscope 162b. Can be taken. As described above, the global method does not need to repeat the operation of positioning the alignment optical system 160 at the retracted position and the measurement position, so that the time required for processing can be shortened.

  In the example described above, the positions of the reference marks RM1 and RM2 are determined in the order of the exposure areas ER1, ER4, ER14, and ER9. By doing so, the moving distance between the X-direction moving stage 172 and the Y-direction moving stage 174 can be shortened, and the time required for processing can be further shortened.

<Coordinate conversion of the positions of the reference marks RM1 and RM2>
The positions of the reference marks RM1 (Xmark_1 (n), Ymark_1 (n)) and the positions of the reference marks RM2 (Xmark_2 (n ), Ymark_2 (n)) is a position in a coordinate system fixed to images taken by the microscopes 162a and 162b. For this reason, in order to calculate the corrected positions of the X-direction moving stage 172 and the Y-direction moving stage 174, it is necessary to convert to a coordinate system fixed to the surface plates 178a and 178b. Hereinafter, the transformation of the coordinate system will be described.

  FIG. 10 shows that one of the four exposure areas ER1, ER4, ER9, or ER14 of the exposure substrate 156c placed on the table 177 is positioned within the irradiable range EA, and the alignment optical system 160 is positioned as the measurement position. FIG. 6 is a diagram showing a state when the reference mark RM1 is photographed with the microscope 162a and the reference mark RM2 is photographed with the microscope 162b. Also in FIG. 10, the upward direction of the drawing is the + X direction, and the left direction of the drawing is the + Y direction.

  As described above, exposure area ER1 is the first measurement exposure area, exposure area ER4 is the second measurement exposure area, exposure area ER9 is the third measurement exposure area, and exposure area ER14 is the fourth measurement. When it is referred to as an exposure area and any one of these measurement exposure areas is indicated, it is referred to as the nth measurement exposure area. Here, n is an integer of any value from 1 to 4.

  The reference mark RM1 is formed at the approximate center of the left side of the measurement exposure region, and the reference mark RM2 is formed at the approximate center of the right side of the measurement exposure region at the originally planned position. However, in the example shown in FIG. 10, both the reference marks RM1 and RM2 are formed at positions displaced from the original positions.

  As shown in FIG. 10, the position in the X direction of the X direction moving stage 172 when the nth measurement exposure region is positioned in the irradiable range EA is Xstg (n), and the Y direction moving stage 174 is Y. The direction position is Ystg (n). Xstg (n) is a position in the X direction (X coordinate) in the coordinate system fixed to the surface plates 178a and 178b with the home position of the X direction moving stage 172 as the origin. Similarly, Ystg (n) is a position in the Y direction (Y coordinate) in the coordinate system fixed to the surface plates 178a and 178b with the home position of the Y direction moving stage 174 as the origin.

  Xstg (n) and Ystg (n) are predetermined amounts for positioning the X-direction moving stage 172 and the Y-direction moving stage 174. As described above, the design positions of the two reference marks RM1 and RM2 formed in each of the four exposure regions ER1, ER4, ER9, and ER12 of the exposure substrate 156c are stored in advance. Xstg (n) and Ystg (n) can be calculated based on the design position of the two reference marks RM1 and RM2 and the position of the table reference mark 179, and the X-direction moving stage 172 and Y It can be stored in the control means of the direction moving stage 174. Since control for driving the X-direction moving stage 172 and the Y-direction moving stage 174 is performed by pulse signals, Xstg (n) and Ystg (n) correspond to the number of pulses of this pulse signal. Here, Xstg (n) and Ystg (n) are amounts converted into units indicating actual lengths such as millimeters.

  Further, as shown in FIG. 10, the center of the nth measurement exposure region is ER-O. Further, an imaging area that can be photographed with the microscope 162a of the alignment optical system 160 is LSA, and an imaging area that can be photographed with the microscope 162b of the alignment optical system 160 is RSA. The center of the imaging area LSA is LSA-O, and the center of the imaging area RSA is RSA-O.

  In the n-th measurement exposure area, the center ER-O of the measurement exposure area is the origin, and the X-direction position (X coordinate) of the center LSA-O of the imaging area LSA in the coordinate system fixed to the exposure substrate 156c is XCCD_1. And Further, the center ER-O of the measurement exposure area is set as the origin, and the Y-direction position (Y coordinate) of the center LSA-O of the imaging area LSA in the coordinate system fixed to the exposure substrate 156c is set as YCCD_1.

  Similarly, the center ER-O of the measurement exposure area is the origin, and the X-direction position (X coordinate) with the center RSA-O of the imaging area RSA in the coordinate system fixed to the exposure substrate 156c is XCCD_2. Further, the center ER-O of the measurement exposure area is set as the origin, and the Y-direction position (Y coordinate) with respect to the center RSA-O of the imaging area RSA in the coordinate system fixed to the exposure substrate 156c is set as YCCD_2. In this way, in the coordinate system fixed to the exposure substrate 156c with the center ER-O of the measurement exposure region as the origin, the coordinates of the center LSA-O of the imaging region LSA are (XCCD_1, YCCD_1), The coordinates of the center RSA-O of the imaging area RSA are (XCCD_2, YCCD_2). As described above, the measurement position of the alignment optical system 160 is a position where the alignment optical system 160 is positioned so that the reference mark RM1 can be photographed with the microscope 162a and the reference mark RM2 can be photographed with the microscope 162b. The position is always a constant position. Therefore, the coordinates of the center LSA-O (XCCD_1, YCCD_1) of the imaging area LSA and the coordinates (XCCD_2, YCCD_2) of the center RSA-O of the imaging area RSA are determined when the measurement position of the alignment optical system 160 is determined. The coordinates can be uniquely determined.

  Also, it is assumed that these coordinates (XCCD_1, YCCD_1) and coordinates (XCCD_2, YCCD_2) are also converted into units indicating the actual length such as millimeters.

  Further, the position of the reference mark RM1 (Xmark_1 (n), Ymark_1 (n)) and the position of the reference mark RM2 (Xmark_2 (n), Ymark_2 (n)) are pixels (pixels) on the image as described above. In the following description, it is assumed that the position of the reference mark RM1 and the position of the reference mark RM2 are converted into units indicating the actual length such as millimeters. For example, a relationship between the number of pixels and the actual length can be obtained by setting a high-precision scale (not shown) as a reference on the table 177 and photographing the scale with the alignment optical system 160. By using this relationship, it is possible to change from the coordinates of the pixel to the coordinates of the actual length.

  Specifically, with the center LSA-O of the imaging area LSA as the origin, the X coordinate in the coordinate system fixed to the imaging area LSA is the position Xmark_1 (n) in the X direction of the reference mark RM1. In addition, the Y coordinate in the Y direction of the reference mark RM1 is the Y coordinate_1 (n) in the coordinate system fixed to the imaging area LSA with the center LSA-O of the imaging area LSA as the origin.

  Similarly, the X coordinate in the coordinate system fixed to the imaging area RSA with the center RSA-O of the imaging area RSA as the origin is the position Xmark_2 (n) in the X direction of the reference mark RM2. Further, the Y coordinate in the coordinate system fixed to the imaging area RSA with the center RSA-O of the imaging area RSA as the origin is the position Ymark_2 (n) in the Y direction of the reference mark RM2.

  By defining as described above, the conversion formula for converting the position of the reference mark RM1 (Xmark_1 (n), Ymark_1 (n)) from the coordinate system fixed to the image to the coordinate system fixed to the surface plates 178a and 178b. Is

とすることができる。また、基準マークＲＭ２の位置（Ｘｍａｒｋ＿２（ｎ），Ｙｍａｒｋ＿２（ｎ））を、画像に固定された座標系から定盤１７８ａと１７８ｂに固定された座標系へ変換する変換式は、

It can be. Further, a conversion equation for converting the position of the reference mark RM2 (Xmark_2 (n), Ymark_2 (n)) from the coordinate system fixed to the image to the coordinate system fixed to the surface plates 178a and 178b is:

It can be. In the global method in the present embodiment, the position of the midpoint between the reference mark RM1 and the reference mark RM2 is used. The position of the midpoint between the reference mark RM1 and the reference mark RM2 is given by

によって、算出することができる。

Can be calculated.

  The variable n used in the above-described equations (1) to (3) is also a variable for specifying the above-described measurement exposure region. In this embodiment, n is an integer of any one of 1 to 4. It is.

By using the above-described equations (1) to (3), the position of the midpoint between the reference mark RM1 and the reference mark RM2 is changed from an image coordinate system fixed to the image to a coordinate system fixed to the surface plates 178a and 178b. Can be converted to
This coordinate conversion process is executed in step S18 of the process procedure of FIG.

  In the global method in the present embodiment, the position of the midpoint between the design position of the reference mark RM1 and the design position of the reference mark RM2 described above is used. The midpoint between the design position of the reference mark RM1 and the design position of the reference mark RM2 is given by

によって、算出することができる。

Can be calculated.

<Calculates six parameters Sx, Sy, θ, ω, Ox and Oy>
After the coordinate conversion in this way, (XM (n), YM (n)) obtained by Expression (3) and (XM_D (n), YM_D (n)) obtained by Expression (4) And the two least squares formulas

Thus, six parameters Sx, Sy, θ, ω, Ox, and Oy can be calculated. The variable n used in the above-described equations (5) and (6) is also a variable for indicating the above-described measurement exposure region. In the present embodiment, n is an integer of any one of 1 to 4. is there.

  In Expressions (5) and (6), Sx indicates the degree of expansion and contraction in the X direction, and indicates the degree when the exposure area is expanded and contracted in the ± X direction as shown in FIG. This Sx corresponds to the magnification in the X direction described above. Sy indicates the degree of expansion and contraction in the Y direction, and indicates the degree when the exposure area is expanded and contracted in the ± Y direction as shown in FIG. This Sy corresponds to the magnification in the Y direction described above. θ indicates the degree of rotation. As shown in FIG. 11C, this indicates the degree when the exposure region rotates. ω indicates the degree of orthogonality, and indicates the degree when the exposure region undergoes shear deformation as shown in FIG. Ox indicates the degree of displacement in the X direction, and indicates the degree when the exposure region is displaced in the ± x direction as shown in FIG. Oy indicates the degree of displacement in the Y direction, and indicates the degree when the exposure region is displaced in the ± y direction as shown in FIG.

  In the process of step S19 in FIG. 9 described above, the six parameters Sx, Sy, θ, ω, Ox, and Oy can be calculated using the least square method shown in the equations (5) and (6).

  By obtaining these six parameters Sx, Sy, θ, ω, Ox and Oy, the position where the X-direction moving stage 172 and the Y-direction moving stage 174 are positioned can be approximated and corrected by a linear expression. it can. That is, the coordinate correction conversion formula using these six parameters

Can be used to obtain a position for positioning the X-direction moving stage 172 and the Y-direction moving stage 174.

In this equation (5), the variable m is a variable indicating the 12 exposure regions ER1 to ER12 of the exposure substrate 156c. Here, m = 1 is the exposure area is ER1, m = 2 is the exposure area is ER2, m = 3 is the exposure area ER3, and m = 4 is the exposure area ER4. It shows that. M = 5, the exposure area is ER8, m = 6, the exposure area is ER7, m = 7, the exposure area is ER6, m = 8, the exposure area is ER5,
m = 9 indicates that the exposure area is ER9. Further, m = 10 indicates that the exposure area is ER10, m = 11 indicates that the exposure area is ER11, and m = 12 indicates that the exposure area is ER12. Hereinafter, when any one of these exposure areas is indicated, it is referred to as the mth exposure area. Here, m is an integer of any value from 1 to 12.

  In the above equation (7), XM_D (m) is the X coordinate before coordinate conversion, and the position in the X direction of the midpoint between the design position of the reference mark RM1 and the design position of the reference mark RM2 It is. YM_D (m) is the Y coordinate before coordinate conversion, and is the position in the Y direction of the midpoint between the design position of the reference mark RM1 and the design position of the reference mark RM2.

  By calculating XM_le (m) and YM_le (m) using Equation (7) described above, the linear component error (hereinafter referred to as linear error) can be corrected by a linear equation. By moving the direction moving stage 172 and the Y direction moving stage 174 to (XM_le (m), YM_le (m), the mth exposure region can be positioned at an appropriate position. If not, XM_le (m) = XM_D (m) and YM_le (m) = YM_D (m), and the X direction moving stage 172 and the Y direction moving stage are at the originally designed positions. The stage 174 is positioned.

<Pattern transfer>
Hereinafter, a procedure for transferring the pattern formed on the reticle 142 to each of the exposure regions ER1 to ER12 of the exposure substrate 156c shown in FIG. 8 using this global method will be described with reference to the flowchart of FIG.

  First, XM_le (1) and YM_le (1) are calculated using equation (7) (step S20). Next, the X-direction moving stage 172 and the Y-direction moving stage 174 are driven to move the table 177 so as to be positioned at XM_le (1) and YM_le (1) calculated in step S19 (step S21). ). With this process, the first exposure area can be positioned at the corrected position.

  Next, exposure light is emitted from the light source 110 to transfer the pattern formed on the reticle 142 to the first exposure region ER1 of the exposure substrate 156c (step 22). It is determined whether or not the pattern has been transferred to all twelve exposure areas ER1 to ER12 (step S23). When it is determined that the process is not performed, the next exposure area (step S24) is processed. The process returns to step S20 described above.

  When it is determined that the pattern has been transferred to all twelve exposure areas ER1 to ER12, the global process ends.

  As described above, in the global method, the movement operation of the alignment optical system 160 to the retracted position and the movement operation to the measurement position are not required for each of the plurality of exposure regions, and thus the pattern formed on the reticle 142 is used as the exposure substrate. The processing time for transferring to 156c can be shortened.

  In the global method, the number of locations for determining the position of the reference mark can be reduced, so that the time required for detection can be shortened. In the example shown in FIG. 8 described above, the case of measuring the positions of the reference marks in the four exposure areas is shown. However, the present invention is not limited to this, and the positions of the reference marks in more than four exposure areas are determined. Also good. By doing in this way, the precision of the correction of the position which positions the stage 172 for X direction movement and the stage 174 for Y direction movement can be improved by the averaging effect.

  In the global method, by determining the positions of the reference marks near the four corners of the exposure substrate, the rotation parameter θ, the expansion / contraction parameter Sx in the X direction, and the expansion / contraction parameter Sy in the Y direction form a reference mark. It is possible to make it less susceptible to the effects of linear errors that occur during the process.

  Furthermore, even if there is a reference mark that is difficult to detect due to damage when manufacturing the exposure substrate, the position can be estimated using the detection result of the position of another reference mark. Therefore, the pattern formed on the reticle 142 can be stably transferred.

  In the above-described embodiment, the exposure area is moved in the order of ER1, ER2, ER3, ER4, ER8, ER7, ER6, ER5, ER9, ER10, ER11, and ER12. As described above, the movement of the exposure area is always set to the adjacent exposure area, so that the movement time of the X-direction movement stage 172 and the Y-direction movement stage 174 can be shortened, and the time required for the entire processing is also reduced. Can be shortened.

<< Error correction using reference board >>
The global method described above is effective when the position of the reference mark formed on the exposure substrate is displaced from the original position due to deformation of the exposure substrate itself. However, the above-mentioned Abbe error is caused by the structure of the X-direction moving stage 172, the Y-direction moving stage 174, and the Z-direction moving stage 176, and the above-described global method alone has a sufficiently high accuracy. In some cases, the pattern cannot be transferred to the exposure substrate. Therefore, the positioning of the X direction moving stage 172 and the Y direction moving stage 174 is corrected using the reference substrate.

<Reference board 158a>
FIG. 12A is a front view schematically showing the reference substrate 158a, and FIG. 12B is an enlarged view showing reference marks formed in one region of the reference substrate 158a.

  In the example shown in FIG. 12, the outer rectangle is a line indicating the outline of the outer shape of the reference substrate 158a. Further, each of a total of twelve squares (ER1 to ER12) including four in the horizontal direction and three in the vertical direction shown inside the outer rectangle represents one area. The reference substrate 158a is not a substrate for transferring a pattern, but a square broken line EB indicating a region shown in FIG. 12A is a virtual one, and the exposure substrate 156 (156a, 156b, This is shown in order to clarify the correspondence between the position and size of the exposure area in 156c). In FIG. 12A, the regions corresponding to the exposure regions ER1 to ER12 of the exposure substrate 156 (156a, 156b, 156c) are denoted by the same reference numerals.

  The reference substrate 158a has substantially the same size as the exposure substrate 156 described above. The reference substrate 158a is made of a glass substrate.

  As shown in FIG. 12B, a plurality of reference marks are formed of chromium in each of the 12 regions ER1 to ER12. In FIG. 12B, these reference marks are indicated by white circles. Each of the reference marks is formed on the reference substrate 158a so that the error is 1 micrometer or less. That is, the reference mark is formed on the reference substrate 158a so as to be included in a range within 1 micrometer with respect to the planned position.

  It is not necessary to determine all the positions of the plurality of reference marks shown in FIG. 12B, and some of them may be selected and used.

  FIG. 13 (a) is a diagram illustrating a configuration using 18 reference marks among a plurality of reference marks for each of the 12 regions ER1 to ER12. In the present embodiment, as shown in FIG. 13A, two black circle reference marks are paired, and these are used as one reference mark pair, and nine reference mark pairs RRM1 to RRM9 are formed. Treat as a single fiducial mark. The nine reference mark pairs RRM1 to RRM9 are located at the center of each of the 12 regions ER1 to ER12, near the four corners, and near the midpoint of the four sides.

  FIG. 13B shows all of the reference mark pairs on the reference substrate 158a. The reference substrate 158a has 12 regions ER1 to ER12, and there are 9 reference mark pairs for each of the 12 regions ER1 to ER12. Therefore, there are 108 reference mark pairs in the entire reference substrate 158a. In FIG. 13B, each of the nine reference mark pairs is indicated by one black square.

  In the following, it is assumed that the design positions of the reference mark pairs used on the reference substrate 158a are stored in advance. Specifically, the design position of the left reference mark (Xmark_des_L (k), Ymark_des_L (k)) of the reference mark pair and the design position of the right reference mark (Xmark_des_R (k), Ymark_des_R (k)) ) Is stored in advance. Note that k = 1 to 108, and as will be described later, k is a variable for specifying the reference mark pair. By moving the X direction moving stage 172 and the Y direction moving stage 174 based on the design position of the reference mark pair, the alignment optical system 160 can photograph the reference mark.

<Detection of the position of the reference mark pair on the reference board 158a>
FIG. 14 is a flowchart showing a procedure for determining the position of the reference mark pair on the reference substrate 158a. A variable k shown in the flowchart of FIG. 14 is a variable for specifying the 108 reference mark pairs shown in FIG. There are 108 reference mark pairs in total for all reference mark pairs RRM1 to RRM9 in the regions ER1 to ER12 of the reference substrate 158a, and the variable k takes a value of 1 to 108. For example, if k = 1, it indicates the reference mark pair RRM1 in the region ER1, and if k = 50, it indicates the reference mark RRM5 in the region ER5.

  First, the alignment optical system 160 is moved from the retracted position to the measurement position (step S31). The retraction position and measurement position of the alignment optical system 160 are the same positions as those of the die-by-die system. The retracted position is preferably the home position of the alignment optical system 160. The measurement position is a position that can ensure that the microscope 162a can capture the left reference mark of the reference mark pair and the microscope 162b can capture the right reference mark of the reference mark pair. I just need it.

  Next, in order to position the first reference mark pair on the reference substrate 158a placed on the table 177 at a position where it can be photographed, an X-direction moving stage 172 and a Y-direction moving stage 174 of the substrate placing stage 170 To move the table 177 (step S32).

  Next, the left reference mark of the reference mark pair is photographed with the microscope 162a of the alignment optical system 160, and the right reference mark of the reference mark pair is photographed with the microscope 162b (step S33).

  Next, the photographed image is stored in an image storage means (not shown), and image processing is performed by an image processing means (not shown), so that the left reference mark image and the right reference mark image of the reference mark pair The image is extracted and the position of the left reference mark (Xmark_L (k), Ymark_L (k)) and the position of the right reference mark (Xmark_R (k), Ymark_R (k)) are calculated. The data is stored in storage means (not shown) (step S34).

  The position of the reference mark pair at this time is a position on the image, and may be a position in an image coordinate system with a pixel (pixel) or the like as a unit, for example, a commonly used length unit such as millimeters. There is no need to use the position. The position of the reference mark pair obtained in this way is a position in the X direction (X coordinate) and a position in the Y direction (Y coordinate).

  By executing the processes of steps S32 to S34 described above, the positions of all the reference mark pairs RRM1 to RRM9 in the regions ER1 to ER12 can be determined and the positions can be stored.

  Next, it is determined whether or not the positions of all the reference mark pairs RRM1 to RRM9 in all the regions ER1 to ER12 have been determined (step S35). If it is determined that no detection has been made, the process returns to step S32 described above in order to process the next reference mark pair (step S36).

  If it is determined in step S35 that the positions of all the reference mark pairs RRM1 to RRM9 in all 12 regions ER1 to ER12 have been determined, the alignment optical system 160 is moved from the measurement position to the retracted position (step). S37).

  In the above-described example, it is preferable to determine the positions of the reference mark pairs in the order of the areas ER1 → ER2 →. → ER4 → ER8 → ER7 .. → ER5 → ER9 → ER10 .. → ER12. By doing so, the moving distance between the X-direction moving stage 172 and the Y-direction moving stage 174 can be shortened, and the time required for processing can be further shortened.

<Coordinate transformation>
Next, in order to convert from the coordinate system fixed to the image to the coordinate system fixed to the surface plates 178a and 178b, the following equations (11) to (13) similar to the equations (1) to (3) described above are used. ) Is used.

  As described above, the position of the left reference mark (Xmark_L (k), Ymark_L (k)) and the position of the right reference mark (Xmark_R (k), Ymark_R (k)) are as follows. As described above, it is a position in the image coordinate system in units of pixels (pixels) or the like on the image. In the following, these positions are converted into units indicating actual lengths such as millimeters. And

  In Expressions (11) and (12), Xstg (k) and Ystg (k) are 12 X-direction movement stages 172 and 12 Y-direction movement stages 174 as in Expressions (1) and (2). This is a predetermined amount for positioning in each of the regions ER1 to ER12.

  In Expression (11), XCCD_L and YCCD_L are the positions of the center of the imaging region of the microscope 162a, similarly to XCCD_1 and YCCD_1 in Expression (1). This XCCD_L is the position in the X direction (X coordinate) in the coordinate system fixed to the reference substrate 158a with the center of each of the 12 regions ER1 to ER12 as the origin, and YCCD_L is the Y direction in the same coordinate system. This is the position (Y coordinate).

  In Expression (12), XCCD_R and YCCD_R are the positions of the center of the imaging region of the microscope 162b, similarly to XCCD_2 and YCCD_2 in Expression (1). This XCCD_R is the position in the X direction (X coordinate) in the coordinate system fixed to the reference substrate 158a with the center of each of the 12 regions ER1 to ER12 as the origin, and YCCD_R is the Y direction in the same coordinate system. This is the position (Y coordinate).

  The position (XM_M (k), YM_M (k)) of the midpoint between the left reference mark and the right reference mark of the reference mark pair is calculated by the above equation (13). Hereinafter, the position of the midpoint is set as the position of the reference mark pair.

  In the embodiment of the present invention, when the reference substrate 158a is used, the position of the midpoint between the left reference mark and the right reference mark of the reference mark pair described above is used. The midpoint between the left reference mark and the right reference mark is

によって、算出することができる。

Can be calculated.

<Extraction of nonlinear error>
Next, using (XM_M (k), YM_M (k)) obtained by Expression (13) and (XRM_D (k), YRM_D (k)) obtained by Expression (14), the following Using equations (15) and (16), six parameters Sx, Sy, θ, ω, Ox, and Oy are calculated by the least square method (step S39).

  K used in the above-described equations (15) and (16) is also a variable for specifying each of the 108 reference mark pairs as described above. In equations (15) and (16), Sx indicates the degree of expansion / contraction in the X direction, Sy indicates the degree of expansion / contraction in the Y direction, θ indicates the degree of rotation, and ω indicates the degree of orthogonality. Ox indicates the degree of displacement in the X direction, and Oy indicates the degree of displacement in the Y direction. A linear error can be extracted by calculating these six parameters Sx, Sy, θ, ω, Ox, and Oy.

  Next, an error composed of nonlinear components (hereinafter referred to as nonlinear errors) (XRM_nle (k), YRM_nle (k))

Calculate using. By using the equation (17), it is possible to calculate the position of the midpoint of the reference mark pair in which the linear error is corrected by approximating with the linear equation using the six parameters calculated in the process of step S39. The non-linear error can be calculated by subtracting the detected position of the midpoint of the reference mark pair from the position where the linear error is corrected by the equation (18).

  Next, using (XRM_nle (k), YRM_nle (k)) obtained by the process of step S40, interpolation using a polynomial is performed, and the range in which the X-direction moving stage 172 and the Y-direction moving stage 174 can move is determined. The nonlinear error is calculated and the result is stored as map data (step S41).

  It is understood that the nonlinear error thus obtained is caused by Abbe error caused by the structure of the X-direction moving stage 172, the Y-direction moving stage 174, and the Z-direction moving stage 176. When the X direction moving stage 172 and the Y direction moving stage 174 are driven, the position is determined based on the non-linear error stored in step S41. It can be positioned on the stage 172 or the Y-direction moving stage 174.

<Reference board 158b>
FIG. 15A is a front view schematically showing the reference substrate 158b, and FIG. 15B is an enlarged view showing the reference mark formed in one region of the reference substrate 158b.

  In the example shown in FIG. 15A, the outer rectangle is a line indicating the outline of the outer shape of the reference substrate 158b. Further, each of a total of twelve squares (ER1 to ER12) including four in the horizontal direction and three in the vertical direction shown inside the outer rectangle represents one area. Similarly to the reference substrate 158a, the reference substrate 158b is not a substrate for transferring a pattern, and the square broken line EB indicating the region shown in FIG. This is shown in order to clarify the correspondence between the position and size of the exposure region in 156 (156a, 156b). In FIG. 15A as well, regions corresponding to the exposure regions ER1 to ER12 of the exposure substrate 156 (156a, 156b) are denoted by the same reference numerals.

  The reference substrate 158b has substantially the same size as the exposure substrate 156 described above. The reference substrate 158b is made of a glass substrate. As will be described later, the reference substrate 158b is preliminarily coated with a photosensitive agent in order to irradiate the reference pattern formed on the reference position reticle.

  As shown in FIG. 15B, a plurality of reference marks are formed of chromium in each of the 12 regions ER1 to ER12. In FIG. 15B, these reference marks are indicated by white squares and black squares. Each of the reference marks is formed on the reference substrate 158b so that the error is 1 micrometer or less. That is, the reference mark is formed on the reference substrate 158b so as to be included in a range within 1 micrometer with respect to the planned position.

  It is not necessary to determine all the positions of the plurality of reference marks shown in FIG. 15B, and some of them may be selected and used. In FIG. 15B, the reference marks to be used are black squares. It showed in. As shown in FIG. 15A, there are nine reference marks IRM1 to IRM9 to be used for each of the twelve regions ER1 to ER12. Therefore, 108 reference marks are used in the entire reference substrate 158b.

  FIG. 16A shows a reference pattern formed on a reference position reticle. The reference position reticle is made of a glass substrate, and a black portion of the reference pattern is a covering portion 42 covered with chrome. A portion indicated by a white solid line in the reference pattern is an uncovered portion 44 that is not covered with chrome and maintains the state of the glass substrate.

<Process of Transferring Reference Pattern to Reference Substrate 158b>
FIG. 17 shows a process for transferring the reference pattern to the reference substrate 158b. It is assumed that the design position of the reference mark used on the reference substrate 158b is stored in advance. By moving the X direction moving stage 172 and the Y direction moving stage 174 based on the design position of the reference mark, the alignment optical system 160 can photograph the reference mark.

  Moreover, the variable j shown in the flowchart of FIG. 17 is a variable for specifying all 108 reference marks shown in FIG. There are 108 reference marks in total of all the reference marks IRM1 to IRM9 in the regions ER1 to ER12 of the reference substrate 158b, and the variable j takes a value of 1 to 108. For example, if j = 1, it indicates the reference mark IRM1 in the region ER1, and if j = 50, it indicates the reference mark IRM5 in the region ER5.

  First, the reference position reticle is arranged in the same manner as the reticle 142 shown in FIG. 1, and the reference substrate 158b is placed on the table 177 of the substrate placement stage 170 (step S51).

  Next, in order to position the first reference mark of the reference substrate 158b placed on the table 177 at a position where the first reference mark can be photographed, the X-direction movement stage 172 and the Y-direction movement stage 174 of the substrate placement stage 170 are placed. Driven to move the table 177 (step S52). When the pattern corresponding to the non-covered portion 44 is transferred, the reference substrate 158b is positioned such that the centers of the IRM1 to IRM9 formed on the reference substrate 158b are the centers of the non-covered portion 44. When exposure light is emitted from the light source 110 in this state, the exposure light can pass through the non-covering portion 44 of the reference position reticle. The exposure light that has passed through the non-covering part 44 is irradiated onto the reference substrate 158b, and a pattern corresponding to the non-covering part 44 is transferred (step S53).

  Next, it is determined whether or not all the reference marks IRM1 to IRM9 in all the regions ER1 to ER12 have been processed (step S54). When it is determined that the processing is not performed, the processing of the above-described steps S52 to S53 is performed again in order to process the next reference mark (step S55).

  By performing the processing described above, as shown in FIG. 16B, the patterns ORM1 to ORM9 corresponding to the non-covering portion 44 are transferred to all the regions ER1 to ER12 of the reference substrate 158b. When there is no movement error in the X direction moving stage 172 and the Y direction moving stage 174, the center of each of the IRM1 to IRM9 formed on the reference substrate 158b is a pattern corresponding to the uncovered portion 44. The patterns ORM1 to ORM9 are transferred so as to coincide with the centers of the ORM1 to ORM9. However, when a movement error occurs in the X direction moving stage 172 and the Y direction moving stage 174, the center is displaced and the patterns ORM1 to ORM9 are transferred as shown in FIG. The In this case, the displacement X_dev in the X direction and the displacement Y_dev in the Y direction shown in FIG.

<Detection of the position of the reference mark on the reference board 158b>
The procedure for determining the position of the reference mark pair on the reference substrate 158b will be described below with reference to the flowchart of FIG. Hereinafter, as shown in FIG. 16B, IRM1 to IRM9 and corresponding patterns ORM1 to ORM9 are combined and referred to as reference marks RRM1 to RRM9. For example, IRM1 and ORM1 are RRM1. Further, as described above, the variable j shown in the flowchart of FIG. 17 specifies the reference mark, and the reference mark is a total of 108 reference marks RRM1 to RRM9 in the regions ER1 to ER12 of the reference substrate 158b. The variable j takes a value from 1 to 108. For example, if j = 1, the reference mark RRM1 in the region ER1 is indicated, and if j = 50, the reference mark RRM5 in the region ER5 is indicated.

  First, the alignment optical system 160 is moved from the retracted position to the measuring position (Step S56). The retraction position and measurement position of the alignment optical system 160 are the same positions as those of the die-by-die system. The retracted position is preferably the home position of the alignment optical system 160. Further, the measurement position may be a position that can ensure that the measurement position is a fixed position where the reference marks RRM1 to RRM9 can be photographed with the microscope 162a or 162b. Note that when the reference substrate 158b is used, it is not necessary to detect two reference marks at the same time. Therefore, the reference marks RRM1 to RRM9 may be photographed with one of the microscopes 162a and 162b.

  Next, in order to position the first reference mark pair on the reference substrate 158a placed on the table 177 at a position where it can be photographed, an X-direction moving stage 172 and a Y-direction moving stage 174 of the substrate placing stage 170 Is driven to move the table 177 (step S57). Next, the reference mark is photographed with the microscope 162a or 162b of the alignment optical system 160 (step S58), and the displacement X_dev (j) in the X direction and the displacement Y_dev (j) in the Y direction of the jth reference mark are calculated. And remember. The displacement X_dev (j) in the X direction of the reference mark and the displacement Y_dev (j) in the Y direction at this time may be an amount in units of pixels (pixels), for example. It need not be in quantities using the unit of length used.

  By executing the processing of steps S57 to S59 described above, the displacement X_dev (j) of all the reference marks RRM1 to RRM9 in the regions ER1 to ER12 and the displacement Y_dev (j) in the Y direction are calculated and stored. Can do.

  Next, it is determined whether or not all the reference mark pairs RRM1 to RRM9 in all the regions ER1 to ER12 have been processed (step S60). When it is determined that the processing is not performed, the processing of the above-described steps S57 to S59 is performed again in order to perform processing of the next reference mark pair (step S61).

  If it is determined in step S60 that all the reference marks RRM1 to RRM9 in all the regions ER1 to ER12 have been processed, the alignment optical system 160 is moved from the measurement position to the retracted position (step S61).

  Thereafter, the same processing as the above-described nonlinear error extraction is performed in steps S38 to S41, whereby the coordinates including the nonlinear error can be calculated for the reference substrate 158b and the result can be stored as map data. In the flowchart of FIG. 17 described above, the processes in steps S38 to S41 are the same as those in FIG.

<< Exposure substrate pattern transfer process >>
As described above, the reference mark error caused by deformation of the exposure substrate 156 (156a, 156b, 156c) can be corrected by the global method. Further, by creating map data using the reference substrate 158a or 158b, a nonlinear error can be extracted and the nonlinear error of the movement between the X direction moving stage 172 and the Y direction moving stage 174 can be corrected. it can. Therefore, when the pattern formed on the reticle 142 is transferred to the exposure substrate 156, first, a process of creating map data is executed using the reference substrate 158a or 158b (step S71 in FIG. 18). This process can be performed by executing the process of FIG. 14 or FIG. 17 described above.

  Next, the pattern formed on the reticle 142 is transferred to the exposure substrate 156 by the global method (step S72 in FIG. 18). This process can be performed by executing the process of FIG. 9 described above. In this case, the position where the X-direction moving stage 172 and the Y-direction moving stage 174 are positioned in the process of step S12 in FIG. 9 is the position stored as the map data created in the process of step S71. is there. Thus, even if there is a movement error between the X direction moving stage 172 and the Y direction moving stage 174, the X direction moving stage 172 and the Y direction moving stage are not affected by the error. The stage 174 can be positioned.

  In this way, the X-direction moving stage 172 and the Y-direction moving stage can be used without using an apparatus such as an interferometer for determining the positions of the X-direction moving stage 172 and the Y-direction moving stage 174. 174 can be accurately positioned at a desired position. Further, even when the exposure substrate 156 is deformed or the like and the position of the reference mark is displaced from the originally designed position, the pattern can be accurately transferred to a desired position.

<< Weighting of Daibidai and Global systems >>
By performing the processing of FIG. 18 described above, the X-direction moving stage 172 and the Y-direction stage 172 can be used even when a linear error occurs in the position of the reference mark due to deformation of the exposure substrate 156 (156a, 156b, 156c). Even when there is an error in positioning with the direction moving stage 174, the position can be corrected and the pattern formed on the reticle 142 can be transferred to the exposure substrate 156.

  However, as described above, the reference mark formed on the exposure substrate 156 is formed by melting the surface of the exposure substrate 156 with a laser beam, or formed by mechanical processing with a drill or the like. . Depending on the accuracy of the method for forming the reference mark, the reference mark may be formed at a position displaced from the originally designed position. Even in such a case, it is necessary to correct the generated error.

  Furthermore, the printed circuit board is made of glass fiber or the like, and nonlinear errors often occur in each process. Here, a method for determining the exposure position including such a nonlinear error of the exposure substrate will be described below.

  In the following, using the exposure substrate 156a, the position of the midpoint between the two reference marks RM1 and RM2 formed on the exposure substrate 156a and the difference between the position of these two reference marks RM1 and the position of RM2 will be described. Use.

  By executing the same process as the process of step S18 in FIG. 9, the position of the midpoint between the reference mark RM1 and the reference mark RM2 (XM (n), YM (n)) is obtained. Further, a difference ΔXM (n) in the X direction and a difference ΔYM (n) in the Y direction can be calculated from these position data. As described above, the position of the reference mark RM1 is (XM_1 (n), YM_1 (n)), and the position of the reference mark RM2 is (XM_2 (n), YM_2 (n)). Therefore, the difference ΔXM (n) is XM_1 (n) −XM_2 (n), and the difference ΔYM (n) is YM_1 (n) −YM_2 (n).

  In the process shown in FIG. 9, the reference marks RM1 and RM2 are detected for the four exposure regions ER1, ER4, ER9, and ER12 in the process using the exposure substrate 156c, but the exposure substrate 156a is used. In this case, the reference marks RM1 and RM2 are detected for the 12 exposure areas ER1 to ER12. Therefore, the variable n described above takes an integer value of 1 to 12. In this case, n = 1 is the exposure region is ER1, n = 4 is the exposure region is ER4, n = 5 is the exposure region is ER8, and n = 8 is the exposure region is ER5. N = 9 indicates that the exposure area is ER9, and n = 12 indicates that the exposure area is ER12. The detection of the reference marks RM1 and RM2 is performed from n = 1 to n = 12. By performing the processing in this way, the X-direction moving stage 172 and the Y-direction moving stage 174 may be moved to the adjacent exposure regions, so that the moving distance of these stages can be shortened. Processing time can be shortened.

  Note that the reference marks RM1 and RM2 may not be detected for all the 12 exposure areas ER1 to ER12, and the reference marks RM1 and RM2 may be detected only for a plurality of selected exposure areas.

  Further, before executing the above-described processing for detecting the reference marks RM1 and RM2, by using the above-described reference substrate 158a or 158b, nonlinear errors are extracted, and the X-direction moving stage 172 and the Y-direction moving stage are extracted. The process of correcting the movement error with respect to 174 is performed in advance, and the X-direction moving stage 172 and the Y-direction moving stage 174 are positioned at the position where the non-linear error is corrected to detect the reference marks RM1 and RM2. To do. In the following, corrected positions for correcting the non-linear error and positioning the X-direction moving stage 172 and the Y-direction moving stage 174 are (X_cor (n), Y_cor (n)). Here, as described above, n is an integer value of 1 to 12 and indicates an exposure area as described above. That is, for example, (X_cor (4), Y_cor (4)) is a corrected stage position for positioning the X direction moving stage 172 and the Y direction moving stage 174 in the exposure region ER4.

  After obtaining the position (XM (n), YM (n)) of the midpoint between the reference marks RM1 and RM2 described above, the difference ΔXM (n) in the X direction, and the difference ΔYM (n) in the Y direction, The process shown in FIG. 19 is executed.

  First, using the position of the midpoint between the reference marks RM1 and RM2 (XM (n), YM (n)) and the corrected position of the stage (X_cor (n), Y_cor (n)), the minimum two points are used. Six parameters Sx, Sy, θ, ω, Ox, and Oy are calculated by multiplication equations (21) and (22) (step S81).

  After executing the processing of step S81, the positions X_le (n) and Y_le (n) obtained by approximating the corrected positions of the midpoints of the two reference marks RM1 and RM2 by the linear expression using Expression (23). ) (Step S82).

  Here, as described above, X_cor (n) and Y_cor (n) in Expression (23) are corrected stages in which nonlinear errors in movement between the X-direction moving stage 172 and the Y-direction moving stage 174 are corrected. Is the position.

  Next, nonlinear error components X_nle (n) and Y_nle (n) are calculated for the position of the midpoint between the two reference marks RM1 and RM2 using Expression (24) (step S83).

Next, six parameters Sx, Sy, θ, ω, Ox, and Oy regarding the position difference are calculated using Expression (25) and Expression (26) (Step S84).

  Next, using the equation (27), the positions ΔX_le (n) and ΔY_le (n) obtained by approximating the difference between the positions of the two reference marks RM1 and RM2 by a linear equation are calculated (step S85).

  From ΔX_le (n) and ΔY_le (n) calculated by Expression (27), nonlinear error components ΔX_nle (n) and ΔY_nle (n) are obtained for the difference in position between the two reference marks RM1 and RM2 according to Expression (28). ) Is calculated (step S86).

  Next, 3σ_le of the linear error components ΔX_le (n) and ΔY_le (n) calculated by Expression (27) is calculated by statistical calculation (step S87). Here, σ_le is a standard deviation between the linear error components ΔX_le (n) and ΔY_le (n). Hereinafter, this 3σ_le is referred to as S_le. Next, 3σ_nle of the nonlinear error components ΔX_nle (m) and ΔY_nle (m) calculated by the equation (28) is calculated by statistical calculation (step S88). Here, σ_nle is a standard deviation between the nonlinear error components ΔX_nle (m) and ΔY_nle (m). Hereinafter, this 3σ_nle is referred to as S_nle. S_nle is error information indicating the degree of the magnitude of the nonlinear error component. Further, error information may be calculated for the nonlinear error components X_nle (n) and Y_nle (n) calculated in step S83 described above as in the case of S_nle and used in the following steps together with S_nle.

  X_le (n) and Y_le (n) calculated in step S82, X_nle (n) and Y_nle (n) calculated in step S83, S_le calculated in step S87, and step S88 Xpos and Ypos are calculated by using equations (29) and (30) using S_nle calculated in (Step S89).

  The X-direction moving stage 172 and the Y-direction moving stage 174 are positioned at Xpos and Ypos calculated by the equations (29) and (30).

  In the above equations (29) and (30), the position (X_le, Y_le) is a position corrected by the global method. On the other hand, the position (X_le + X_nle, Y_le + Y_nle) is a position corrected by the die-by-die method.

  If there is a large error when the two reference marks RM1 and RM2 are formed on the exposure substrate 156 (including the case where the deformation of the exposure substrate 156 is higher than the third order). S_nle becomes large. Further, when the secondary error of the exposure substrate 156 is small, S_le = 0. In this case, it is considered that the error occurred at random, and Equations (29) and (30) are

となり、グローバル方式によって、適切な位置にパターンを転写することができる。

Thus, the pattern can be transferred to an appropriate position by the global method.

  On the other hand, if the error when the two reference marks RM1 and RM2 are formed on the exposure substrate 156 is small, S_nle = 0. Furthermore, when the secondary error of the exposure substrate 156 is large, S_le is large. The error in this case is considered to be due to the second-order distortion error of the exposure substrate 156. Equations (29) and (30) are

となり、ダイバイダイ方式によって、適切な位置にパターンを転写することができる。

Thus, the pattern can be transferred to an appropriate position by the die-by-die method.

  Further, when neither S_nle nor S_le is small, the position is calculated by Expression (29) and Expression (30).

  Note that, when calculating the equations (29) and (30), the coefficient D may be used as S_nle = S_nle × D. The coefficient D is a coefficient that can determine whether to place importance on the global method or on the die-by-die method, and is a coefficient that can be determined by the user's intention. For example, when D> 1 is set, the global method can be emphasized, and when D <1, the die-by-die method can be emphasized.

<< Error alternative >>
In the processing described above, when the processing of FIG. 19 is performed, the difference ΔXM (n) in the X direction and the difference ΔYM (n) in the Y direction are obtained. Since the two reference marks RM1 and RM2 are arranged along the X direction, the difference ΔXM (n) in the X direction corresponds to Sx indicating the degree of expansion / contraction in the X direction, and the difference ΔYM (n) in the Y direction. Corresponds to θ indicating the degree of rotation.

  Therefore, after calculating the six parameters Sx, Sy, θ, ω, Ox, and Oy in the process of step S84 described above, Sx is replaced with the difference ΔXM (n) in the X direction, and θ is the difference in the Y direction. Instead of ΔYM (n), the processing shown in FIG. 19 may be performed. Note that it is not necessary to replace both Sx and θ, and processing may be performed by replacing only one of them.

  In the first embodiment described above, the control device 199 causes the first position correction means, the second position correction means, the reference substrate position control means, the reference substrate position storage means, and the reference substrate exposure means to Reference substrate position correction calculation storage means, exposure substrate position control means, exposure substrate position storage means, exposure substrate reference mark position storage means, and linear error correction calculation means are configured.

<< Intelligent global method >>
The exposed substrate may be deformed into a shape that can be approximated by a quadratic equation or a cubic equation, for example, when it is thermally deformed during manufacturing or when it is cut into a predetermined size. FIG. 24 illustrates a case where (a) the deformation of the exposure substrate is approximated by a quadratic expression and (b) a case where the deformation of the exposure substrate is approximated by a cubic expression. The exposed substrate is often deformed as shown in FIGS. 24A and 24A during the manufacturing process. Therefore, the position of the reference mark on the exposure substrate is also displaced to a position that can be approximated by a quadratic expression, a cubic expression, or the like. Since the displacement of this position can be regarded as an error in the position of the reference mark, an error based on the displacement of the position of the reference mark can also be approximated by a quadratic expression or a cubic expression. In general, deformation of the shape of the exposure substrate often causes a positional error that can be approximated by an order expression up to a third order expression. Therefore, in the following description, a case where the deformation of the shape of the exposure substrate can be approximated by a cubic equation including a quadratic term will be described as an example.

  On the other hand, the reference mark on the exposure substrate 156 is formed by melting the surface of the exposure substrate 156 with laser light, or formed by mechanical processing with a drill or the like. For this reason, depending on the accuracy at the time of forming the reference mark, the reference mark may be formed at an unexpected position different from the originally designed position. This displacement is a random displacement and causes a random error in the position of the reference mark. Further, such a random error in the position of the reference mark is an error that can be approximated by a higher-order expression of a quaternary expression or higher when compared with an error that can be approximated by a cubic expression as described above. It can be considered. Therefore, in the present embodiment, the error generated at the position of the reference mark is separated into two types, that is, the error based on the above-described exposure substrate deformation and the error based on the formation of the reference mark, and the former is approximated by a cubic equation. An error that can be performed (third-order approximation error) is assumed, and the latter is assumed to be an error (random error) that can be approximated by a higher-order equation higher than the fourth-order equation.

  In the intelligent global method according to the present embodiment, when correcting the position error of the reference mark, the optimum position of the exposure substrate at the time of exposure depends on which of the cubic error and the random error is the dominant error. Change the correction method. That is, among the errors of the reference mark position, it is determined which error is dominant based on the magnitude of the cubic approximation error and the random error, and based on the result, the above-described die-by-die method and The exposure position error is corrected by a method similar to the weighting with the global method. A method of correcting the error of the exposed substrate position during exposure in this way is called “intelligent global method”. The intelligent global method uses not only the cubic expression but also the quaternary expression and the quintic expression as exposure criteria based on the position error and random error that can be approximated by higher order errors than the cubic expression. It is also possible to correct an error in the exposure position at the time. According to this intelligent global process, the target position for positioning the mounting table on which the exposure substrate is placed at the time of exposure can be set to a more accurate position.

  FIG. 25 shows a flowchart of the processing procedure of the intelligent global method. Hereinafter, the intelligent global method will be described in detail with reference to FIG. In the following, an explanation will be given by taking as an example an intelligent global method using a cubic approximation error and a random error as criteria.

  First, a reference mark (exposure substrate reference mark) of each exposure area on the exposure substrate is detected. This detection is performed in the same manner as described in FIGS. 9, 14 and 17 (step S101). FIG. 26 shows a schematic view of an example of an exposure substrate used in intelligent global processing. The exposure substrate 156d has four exposure regions ER (1,1) to ER (4,4). These exposure areas are generally defined as ER (i, j) (i = 1 to 4, j = 1 to 4 natural numbers). Each exposure region has four exposure substrate reference marks RM1 (i, j), RM2 (i, j), RM3 (i, j), and RM4 (i, j). In the present embodiment, the exposure substrate reference mark is detected as a set of two exposure substrate reference marks.

  When detecting the position of the exposure substrate reference mark, it is possible to sequentially detect all the exposure substrate reference marks in all the exposure regions. However, in order to shorten the detection time of the exposure substrate reference mark, it is better to omit detection of some exposure substrate reference marks. In this case, the position of the omitted exposure substrate reference mark is preferably replaced with the position of another exposure substrate reference mark in the vicinity thereof. An example of this substitution will be described using the exposure substrate 156e shown in FIG. In the exposure substrate 156e, an exposure substrate reference mark for which detection is omitted is not described or indicated by a dotted line. As shown in the exposure substrate 156e, the detection processing of the exposure substrate reference marks RM3 (1, 1) and RM4 (1, 1) in the exposure region ER (1, 1) is omitted. The positions of these exposure substrate reference marks are calculated based on the positions of the exposure substrate reference marks RM1 (2, 1) and RM2 (2, 1) in the vicinity thereof. Similarly, in the exposure substrate 156e, detection of exposure substrate reference marks in other exposure regions can be omitted. When detecting the exposure substrate reference marks of the exposure substrate 156d shown in FIG. 26, it is necessary to detect 32 sets (64 pieces) of the exposure substrate reference marks, whereas the exposure substrate 156e shown in FIG. When detecting the exposure substrate reference mark, it is sufficient to detect 20 sets (40 pieces), and the time for detecting the exposure substrate reference mark can be shortened. In FIGS. 26 and 27, the exposure reference mark to be detected is indicated by a black square.

  An example in which the detection of the exposure substrate reference mark can be further omitted is shown in FIG. In the exposure substrate 156f, detection of the exposure substrate reference marks RM1 (1,2) and RM2 (1,2) in the exposure region ER (1,2) is omitted. The positions of these exposure substrate reference marks are based on the positions of the exposure substrate reference mark RM2 (1,1) in the exposure region ER (1,2) and RM1 (1,3) in the exposure region ER (1,2). Can be calculated. For other exposure substrate reference marks, at locations where the boundary of the exposure region is adjacent, by detecting at least one exposure substrate reference mark, an exposure substrate in the vicinity of the exposure substrate reference mark in the other exposure region Detection of the reference mark can be omitted. As a result, in the case of the exposure substrate 156e, it is only necessary to detect 15 sets (30) of exposure substrate reference marks indicated by the black squares shown in the figure. Thus, by omitting a large number of exposure substrate reference marks, the number of times the alignment optical system is moved and stopped can be reduced, and the time required for detection of the reference marks can be shortened. Therefore, it is preferable because the throughput of the exposure process can be increased.

  It is also possible to detect reference marks only for a plurality of selected exposure areas without detecting the reference marks in some exposure areas. In this case, the position of the exposure region where detection is omitted can be calculated by approximately complementing based on the position of the exposure substrate reference mark in the adjacent exposure region. Also, when there is an exposure area where the detection of the reference mark could not be performed for some reason, similarly, the position of the exposure area is based on the position of the exposure substrate reference mark in the adjacent exposure area, Approximate complements can be calculated.

  One exposure area does not necessarily have four exposure substrate reference marks. For example, as shown in FIG. 4A, the processing according to the present method can be performed even when each exposure region has two exposure substrate reference marks. However, in order to obtain an exposure position in which an error in the position of the exposure substrate reference mark is more accurately corrected, each exposure region preferably has at least four exposure substrate reference marks.

  After performing the process of step S101 described above, the position of the exposure substrate reference mark is calculated from the detection result of the position of the exposure substrate reference mark (step S102). “Calculating the position of the exposure substrate reference mark” means that if the detection of the position of a part of the exposure substrate reference mark is omitted, the omitted exposure is based on the positions of other exposure substrate reference marks in the vicinity. It also includes calculating the position of the substrate reference mark. The exposure substrate reference mark position is calculated using equations (1) to (2) for converting from a coordinate system fixed to the image to a coordinate system fixed to the surface plates 178a and 178b. The same method as described above can be used.

  As pre-processing for calculating the position of the exposure substrate reference mark, it is preferable to perform error correction using the reference substrate as described above. That is, it is preferable to perform in advance a process for correcting an error caused by the structure of the X-direction moving stage 172 and the Y-direction moving stage 174 by using a reference substrate similar to the above-described reference substrate 158a or 158b. In the following, the positions of the X-direction moving stage 172 and the Y-direction moving stage 174 after correcting errors caused by the structures of the X-direction moving stage 172 and the Y-direction moving stage 174 are expressed as (X_cor (i, j ), Y_cor (i, j)). Here, i and j take a natural number of 1 to 4, and indicate an exposure area. For example, (X_cor (i, j), Y_cor (i, j)) is a corrected value for positioning the X-direction moving stage 172 and the Y-direction moving stage 174 in the exposure region ER (i, j). The position of the stage.

  Next, an entire area error parameter value, which is a value characterizing an error based on the displacement of the position of the exposure substrate reference mark, is calculated over the entire exposure substrate using the least square method based on the position of the exposure substrate reference mark (step S103). Here, the entire area error parameter is a parameter indicating an overall error occurring over the entire exposure substrate. Specifically, the six parameters Sx, Sy, θ obtained in the above-described global processing are used. , Ω, Ox, and Oy. These parameters can be calculated by executing processing similar to the processing in steps S18 and S19 in FIG. 9 based on the position of the exposure substrate reference mark calculated as described above. Specifically, the position of the midpoint of the paired reference marks is obtained using an expression similar to Expression (3). Furthermore, using the least square formulas (21) and (22), approximation by the least square method is performed for (i, j) instead of n based on X_cor (i, j), Y_cor (i, j). By doing so, the entire region error parameter can be calculated.

  Next, in each of the detection areas, detection area error parameter values Sx (i, j), Sy (i, j) that characterize an error based on the displacement of the position of the exposure substrate reference mark based on the positions of at least two exposure substrate reference marks. ), Θx (i, j) and θy (i, j) are calculated (step S104). Here, the detection area is an area for calculating each detection area error parameter value. Although the detection area may be the same area as the exposure area, a plurality of areas obtained by subdividing each of the exposure areas may be used as the detection area in order to improve the accuracy of this processing. In some cases, an area having a different size, position, and shape from the exposure area may be used as the detection area. Although it has been described that the detection of some of the exposure substrate reference marks can be omitted in the processing of step S101 described above, the exposure substrate in the omitted exposure region is similarly applied to the detection regions in which the detection of the exposure substrate reference marks is omitted. The position of the reference mark can be calculated based on the positions of other exposure substrate reference marks in the vicinity thereof. Hereinafter, a case where the exposure area and the detection area are the same area will be described as an example. For this reason, the same symbol as that of the exposure region is used as the symbol of the detection region, and is described as a detection region ER (i, j).

  The detection area error parameter value calculated in the process of step S104 described above is, for example, the degree of expansion / contraction of the detection area in the X direction and the Y direction, or the distortion or rotation of each of the detection areas in the X direction and the Y direction. Is a value characterizing an error based on each displacement or deformation of the detection area. An example of the detection area error parameter will be described with reference to FIG. FIG. 29 shows the shape of the detection area before and after deformation of the detection area and the position of the exposure substrate reference mark by a broken line and a solid line, respectively. In this example, the positions of RM1 (i, j) and RM3 (i, j) are not displaced, but the positions of RM2 (i, j) and RM4 (i, j) are displaced. Dx and Dy indicate the distance between the centers of two exposure substrate reference marks adjacent in the X direction and the Y direction before the detection area is deformed. The length obtained by subtracting Dx or Dy from the difference between the position coordinate components in the X direction or Y direction of the exposure substrate reference mark adjacent in the X direction or Y direction is Sx (i, j) (1), Sx (i, j ) (2), Sy (i, j) (1) and Sy (i, j) (2). Sx (i, j) (1) and Sy (i, j) (2) are average values of Sx (i, j) (1) and Sx (i, j) (2). ) (Sy (i, j)) can be obtained as an average value. These Sx (i, j) and Sy (i, j) are detection region error parameters indicating the degree of error of expansion or contraction in the X direction or Y direction in the detection region ER (i, j).

  Further, the difference between the position coordinate components in the Y direction or the X direction of the exposure substrate reference mark adjacent in the X direction or the Y direction is expressed as θx (i, j) (1), θx (i, j) (2), θy ( i, j) (1) and θy (i, j) (2). θx (i, j) is averaged between θx (i, j) (1) and θx (i, j) (2), and θy (i, j) (1) and θy (i, j) (2 ) (Y, i, j) can be obtained as an average value. These θx (i, j) and θy (i, j) are the degree of shear deformation in the X direction or Y direction in the detection region ER (i, j), or θx (i, j) and θy (i, j, When the magnitude of j) is the same, it is a detection area error parameter indicating an error corresponding to the degree of rotation.

  In general, the detection area error parameters Sx (i, j), Sy (i, j), θx (i, j), and θy (i, j) are the position coordinates of a plurality of exposure substrate reference marks in a certain detection area. Can be calculated based on the difference. Therefore, the detection area error parameter value corresponds to the first derivative of the position of the exposure substrate reference mark. The detection area error parameter is not limited to Sx (i, j), Sy (i, j), θx (i, j), and θy (i, j), and corresponds to the first derivative of the position of the exposure substrate reference mark. Any device may be used as long as it characterizes an error based on the displacement of the position of the exposure substrate reference mark.

  When the shape of the exposure substrate is approximated by a quadratic equation due to deformation of the exposure substrate, the detection region error parameter is a value corresponding to the quadratic coefficient of the quadratic equation.

  In addition, the least square method similar to the equations (5) and (6) is used based on the coordinates of the position of the exposure substrate reference mark included in the detection region ER (i, j), instead of using the above-described difference. Thus, the six parameters Sx (i, j), Sy (i, j), θ (i, j), ω (i, j), Ox (i, j) and Oy (i, j) of each detection region j) may be calculated and used as detection region error parameters.

  Next, in each detection region, a linear component of the detection region error parameter value is calculated using the least square method based on the detection region error parameter value (step S105). That is, the position of the midpoint of the detection area ER (i, j) and the detection area error parameters Sx (i, j), Sy (i, j), θx (i, j), and θy (i, j) The linear component of the detection area error parameter can be obtained by executing the same process as the process of step S19 in FIG. Specifically, as described in step S103, first, the position of the midpoint of the detection area ER (i, j) is obtained. Next, Sx (i, j) is substituted for ΔXM (n) and Sy (i, j) is substituted for ΔYM (n) by using the same equation as the equations (25) to (26) of the least square method. The six parameters Sx, Sy, θ, ω, Ox and Oy can be calculated by using the least squares approximation for (i, j) instead of n. Further, the linear components Sx_le (i, j) and Sy_le (i, j) of the detection region error parameter value can be calculated in the same manner as Expression (27). By performing similar processing for θx (i, j) and θy (i, j), the linear components θx_le (i, j) and θy_le (i, j) of the detection region error parameter value can be calculated. .

  Next, a difference of at least the first floor or more of detection area error parameter values in two adjacent detection areas is calculated (step S106). Here, “difference on the first floor” refers to a difference between detection area error parameter values in two adjacent detection areas. The “second floor difference” is obtained by further calculating the difference of the first floor difference of the detection area error parameter value. Similarly, the difference when the difference is calculated n times is referred to as “n-th floor difference”.

  Note that, as described with respect to step S104 described above, generally, the detection region error parameter is calculated based on the difference in position coordinates of the exposure substrate reference mark. Therefore, the detection area error parameter corresponds to the first order difference (first order differentiation) of the position of the exposure substrate reference mark. Similarly, the first-order difference (first-order differentiation) of the detection area error parameter value corresponds to the second-order difference (second-order differentiation) of the position of the exposure substrate reference mark. In general, the n-th order difference (n-order derivative) of the detection region error parameter value corresponds to the n + 1-order difference (n + 1-order derivative) of the position of the exposure substrate reference mark.

  In the following description, only the first-order differences ΔSx (i, j), ΔSy (i, j), Δθx (i, j), and Δθy (i, j) of detection area error parameter values in two adjacent detection areas are used. The case of calculating will be described.

  Next, using the least-squares method based on the first-order difference, the differential linear components ΔSx (i, j) _le, ΔSy (i, j) _le, Δθx (i, j) _le, and Δθy (i, j) _le Is calculated (step S107). The calculation of the differential linear component using the least square method is performed using equations similar to the equations (25) to (27), similarly to the calculation of the linear component of the region error parameter value in step S105 described above. Can do.

  As described above, since the detection region error parameter corresponds to the first derivative of the position of the exposure substrate reference mark, the difference in the detection region error parameter value corresponds to the second derivative of the position of the exposure substrate reference mark. Become. Therefore, when the shape is approximated by a cubic equation due to deformation of the exposure substrate, the differential linear component is a value corresponding to the cubic coefficient of the cubic equation.

Ｓｙ＿ｎｌｅ（ｉ，ｊ）、θｘ＿ｎｌｅ（ｉ，ｊ）およびθｙ＿ｎｌｅ（ｉ，ｊ）についても、Ｓｙ＿ｌｅ＿ｔｏｔａｌ（ｉ，ｊ）、θｘ＿ｌｅ＿ｔｏｔａｌ（ｉ，ｊ）およびθｙ＿ｌｅ＿ｔｏｔａｌ（ｉ，ｊ）を式（３５）と同様に算出することにより、式（３６）と同様な式を用いて算出することができる。 Next, for each detection region, a detection region error parameter value such as Sx (i, j), a linear component of a detection region error parameter value such as Sx_le (i, j), ΔSx (i, j) _le, and the like Error information S_Sx, S_Sy, S_θx, S_θy such as error Sx_nle (i, j) of the detection region error parameter value is calculated based on the cumulative sum of the difference linear components of (step S108). For example, the detection area error parameter value error Sx_nle (i, j) for Sx is calculated from the detection area error parameter value Sx (i, j) to the linear component Sx_le (i, j) of the detection area error parameter value. This is performed by subtracting the sum Sx_le_total (i, j) of the difference linear component ΔSx (i, j) _le. That is, Sx_nle (i, j) can be calculated by the equations (35) and (36).

For Sy_nle (i, j), θx_nle (i, j), and θy_nle (i, j), Sy_le_total (i, j), θx_le_total (i, j), and θy_le_total (i, j) are the same as in equation (35). Can be calculated using the same expression as Expression (36).

  As is clear from the above calculation process, the linear component Sx_le (i, j) and the like of the detection region error parameter value correspond to the first derivative of the position. Further, the difference linear component ΔSx (i, j) _le and the like correspond to the secondary differential of the position, and the cumulative sum of the difference linear components corresponds to the integration thereof. Therefore, Sx_le_total (i, j) obtained by adding the cumulative sum of the difference linear components to the linear component of the detection region error parameter value corresponds to a cubic approximation error among errors based on the displacement of the position. Since the cumulative sum corresponds to integration, when the differential linear component can be expressed by a mathematical formula, the integral value of the mathematical formula can be used as the cumulative sum.

  On the other hand, the error Sx_nle (i, j) of the detection region error parameter value is obtained by subtracting the cubic approximation error from the entire error based on the displacement of the position, and can be said to correspond to a random error. .

  In the above-described step S106, when the difference of the second or higher floor of the detection area error parameter value in the two adjacent detection areas is calculated, the cumulative sum of the difference linear components ΔSx (i, j) _le is calculated. In addition, it is necessary to calculate the cumulative sum of the number of times based on the difference rank. For example, when the difference of the second floor is calculated, the cumulative sum of the second-order difference linear components is calculated, the cumulative sum of the cumulative sum is calculated, and the cumulative sum of the cumulative sum is calculated as Sx_le_total (i, j) Add to. Similarly, when the difference between the third floor and the nth floor is calculated, the cumulative sum is repeated n times in the same procedure and added to Sx_le_total (i, j). Based on this Sx_le_total (i, j), the error Sx_nle (i, j) of the detection region error parameter value can be calculated. The same applies to ΔSy (i, j) _le, Δθx (i, j) _le, and Δθy (i, j) _le.

  Next, error information S_Sx, S_Sy, S_θx, and S_θy corresponding to variations in the error Sx_nle (i, j) of the detection region error parameter value is calculated by statistical calculation. Specifically, for example, the error information of the detection region error parameter value error can be calculated by obtaining the standard deviation (σ) such as the error Sx_nle (i, j) of the detection region error parameter value. Further, twice the σ (2σ) or three times σ (3σ) or the like may be used as error information of the detection region error parameter value error. As an example, 3σ calculated from Sx_nle (i, j) or the like can be used as error information S_Sx of the error of the detection region error parameter value. Similarly, 3σ calculated from Sy_nle (i, j), etc., θx_nle (i, j), etc., or θy_nle (i, j), etc. is set as error information S_Sy, S_θx, or S_θy of the error of the detection region error parameter value. Can do. The error information corresponding to the error variation of the detection region error parameter value is not limited to the standard deviation as long as it statistically indicates the error variation, and any information can be used.

Next, based on the error information S_Sx, S_Sy, S_θx, S_θy of the error of the detection region error parameter value, an error based on the cumulative sum of the linear component and the differential linear component of the detection region error parameter value (corresponding to a cubic approximation error) And a weighting coefficient W that indicates a ratio of the magnitude of the error that is not based on (corresponding to a random error) (step S109). Here, “indicating the ratio of size” means indicating which is the dominant error based on the size of the error corresponding to the cubic approximation error and the error corresponding to the random error. To do. As an example of the weighting coefficient, the error information of the detection area error parameter value calculated in step S108 can be calculated based on a value obtained by dividing the error information by the detection area error parameter value. For example, the weighting coefficient is calculated by Expression (37). be able to.

  Next, a target position for positioning the mounting table is calculated based on the position of the exposure substrate reference mark, the entire area error parameter value, and the weighting coefficient W (step S110).

  For example, when the weighting coefficient W = 0 calculated by the equation (36) corresponds to a case where the reference mark position error is only a cubic approximation error, the substrate displacement and the position of the exposure substrate reference mark associated therewith. This is a case where the displacement of is not random. Therefore, it can be said that the position of the exposure substrate reference mark calculated in step S102 is probable. Therefore, when the weighting coefficient W = 0, the target position for positioning the mounting table is calculated based on the position of the exposure substrate reference mark calculated in step S102. A target position calculated by this method is (Xd, Yd). For the calculation of the target position (Xd, Yd), the same calculation method as the position correction by the above-described die-by-die method can be used. Further, the target position (Xd, Yd) is calculated based on a value corresponding to the cubic approximation error of Sx_le_total (i, j), Sy_le_total (i, j), θx_le_total (i, j), and θy_le_total (i, j). It can be performed.

  On the other hand, when the weighting coefficient W = 1 calculated by Expression (36) corresponds to the case where the error of the reference mark position is only a random error. Therefore, it cannot be said that the position of the exposure substrate reference mark calculated in step S102 is likely. Therefore, by calculating the target position for positioning the mounting table for each exposure region using the entire area error parameter value calculated in step S103, the target position for positioning the mounting table on which the exposure substrate is placed at the time of exposure is more accurate. It can be a position. The target position calculated by this method is (Xg, Yg).

In general, the weighting coefficient W is used to weight the two target position calculation methods. For example, the target position (Xpos, Ypos) can be calculated using the following equations (38) and (39).

  The calculation method of the weighting coefficient and the target position is not limited to the above example, and it is for determining which is the dominant error based on the magnitude of the cubic approximation error and the random error. This is a coefficient, and the calculation method can be changed as appropriate based on the meaning of the weighting coefficient to be reflected in the calculation of the target position of the exposure substrate. Further, the weighting coefficient is not limited to one, and a weighting coefficient may be calculated for each detection region error parameter value and used for weighting.

  Next, the mounting table is positioned at the target position calculated as described above, and the pattern is transferred to the exposure substrate (step S111).

  As described above, the processing based on the intelligent global method has been described for the case where the cubic approximation error and the random error are used as the criterion. However, Step S106 and Step S107 are repeated a predetermined number of times, and an appropriate number of differences are accumulated in Step S107. By calculating the sum, it is intelligent to use the error of the exposure substrate reference mark position and random error as a criterion for the deformation of the higher order substrate than the cubic equation, such as quaternary equation and quintic equation. A global method can be performed.

  30A and 30B show examples of position error correction by the intelligent global method described above. In the figure, the arrows indicate the correction direction and the correction magnitude obtained by the intelligent global method. As can be seen from this figure, when a positional error occurs such that the deformation of the exposure substrate is approximated by a quadratic expression or a cubic expression, a very excellent error correction result can be obtained. In addition, as shown in FIG. 30C, the error can be corrected even when the change in the magnitude of the rotation approximated by the cubic equation is caused by the intelligent global process.

  Using intelligent global processing, even if there is an exposure area where the exposure substrate reference mark could not be detected for some reason, the overall position error parameter value is used to determine the target position for positioning the mounting table for each exposure area. Can be calculated. In addition, even when some of the exposure substrate reference marks cannot be detected, the positions of the exposure substrate reference marks that cannot be detected can be approximately complemented based on the positions of the peripheral exposure substrate reference marks that can be detected. it can. Therefore, it is possible to perform exposure even for an exposure area where detection of the exposure substrate reference mark is impossible for some reason.

  Through the intelligent global method described above, it is possible to perform exposure at an exposure position in consideration of a random error in the position of the exposure substrate reference mark. Further, by omitting detection of some exposure substrate reference marks, the throughput of exposure processing can be increased. In addition, since exposure processing can be performed even when there is an exposure region in which the exposure substrate reference mark cannot be detected for some reason, more reliable exposure processing is possible. Furthermore, since errors due to the stage structure and the like are often not random errors, the exposure substrate can be obtained by using the intelligent global method even when correcting the error due to the stage structure or the like using the reference substrate. It is possible to perform both correction of the error and correction of the error caused by the structure of the stage. That is, it is possible to omit correction of errors caused by the structure of the stage using the reference substrate.

<<<< Second Embodiment >>>>
FIG. 20 schematically shows a projection exposure apparatus 100 according to the second embodiment of the present invention. Similar to the projection exposure apparatus 100, the projection exposure apparatus 200 is mainly for manufacturing a printed wiring board.

  The projection exposure apparatus 200 is a projection exposure apparatus that uses a digital micromirror device (Digital_Micromirror_Device), and is a projection exposure apparatus that can transfer a pattern onto an exposure substrate without using a reticle.

<< Projection optical system >>
The projection optical system includes a light source 210, a fiber 212, and a rod 214.
The light source 210 has a plurality of ultraviolet LED light sources (not shown). The light beam emitted from the light source 210 is incident on the fiber 212, and the fiber 212 collects the incident light beam and emits the illumination light beam from the emission portion of the fiber 212. The illumination light beam emitted from the fiber 212 is incident on the rod 214, and the rod 214 emits the illuminance of the incident illumination light beam close to uniform.

<Digital micromirror device optical system>
An illumination relay optical system 222, a deflection mirror 224, and a digital micromirror device 230 are arranged in the traveling direction of the light beam emitted from the rod 214. The light beam emitted from the rod 214 is adjusted by the illumination relay optical system 222 and the deflecting mirror 224 so as to be the size of the reflecting surface 232 of the digital micromirror device 230 and irradiates the digital micromirror device 230. The reflection surface 232 of the digital micromirror device 230 includes a plurality of mirrors that can be driven independently. By driving the plurality of mirrors, the angles of the plurality of mirrors can be changed to reflect the light incident on the plurality of mirrors in a desired direction. The plurality of mirrors are two-dimensionally arranged, for example, 800 × 600, 1280 × 1024, 1980 × 1080, and the like.

<Enlarged lighting system>
An enlarged illumination system 240 is disposed below the digital micromirror device 230. The magnified illumination system 240 includes a plurality of lenses. A pupil position exists in the optical path in the magnified illumination system 240, and a blind 242 is disposed at the pupil position. An opening 244 is formed in the blind 242.

  As described above, the plurality of mirrors of the digital micromirror device 230 can change angles. In the present embodiment, the angles of the plurality of mirrors of the digital micromirror device 230 are driven so as to be the first angle or the second angle. The first angle is such that the light beam incident on the plurality of mirrors is directed to the opening 244 of the blind 242. When the angles of the plurality of mirrors are the first angle, the light beam emitted from the light source 210 can travel downward through the opening 244 of the blind 242. On the other hand, the second angle is such that the light beam incident on the plurality of mirrors is directed to a portion that is not the opening 244 of the blind 242. When the angle of the plurality of mirrors is the second angle, the light beam emitted from the light source 210 is blocked by the blind 242 and cannot pass through the opening 244.

  A microarray lens 250 is disposed below the magnified illumination system 240. The microarray lens 250 includes a plurality of microlenses corresponding to each of the plurality of mirrors of the digital micromirror device 230. When the angles of the plurality of mirrors become the first angle, the light beam emitted from the light source 210 passes through the opening 244 of the blind 242 and enters the microarray lens 250. The microarray lens 250 condenses light incident on each microlens and forms a light beam spot at a position LS below the microarray lens 250. The luminous flux spot has a size of several micrometers to several tens of micrometers.

<Projection Lens 150, Alignment Optical System 160, Substrate Placement Stage 170>
Below the microarray lens 250, a projection lens 150, an alignment optical system 160, and a substrate placement stage 170 are arranged. The projection lens 150, the alignment optical system 160, and the substrate mounting stage 170 have the same configurations and functions as those of the projection exposure apparatus 100 in the first embodiment, and are denoted by the same reference numerals.

  The exposure substrate 156 is placed on the table 177 of the substrate placement stage 170 as in the first embodiment. The exposure substrate 156 may be any of the exposure substrates 156a, 156b, or 156c described in the first embodiment. On the exposure substrate 156, an image of the light beam spot formed at the position LS is formed. By forming the image of the light beam spot on the exposure substrate 156, the portion where the image of the light beam spot is formed can be exposed. As a result, by controlling the angle of each of the plurality of mirrors to be either the first angle or the second angle described above, the surface of the exposure substrate 156 is a place where the image of the light beam spot is formed. And a portion that is not formed. By creating on the exposure substrate 156 a place where the image of the light beam spot is formed and a place where the image of the light beam spot is not formed, it is possible to do the same as the pattern transfer.

  FIG. 21 is an enlarged view showing the image 260 of the light beam spot formed on the exposure substrate 156 and the exposure substrate 156. FIG. 21 is a view showing a part of the image 260 of the light beam spot formed on the exposure substrate 156 and a part of the exposure substrate 156. In FIG. 21, the image 260 of the light beam spot is indicated by a white circle.

  As shown in FIG. 21, the image 260 of the light beam spot formed on the exposure substrate 156 is a discrete image in which the positions of adjacent images are separated. For this reason, the locations where the exposure substrate 156 is exposed are also discrete, and it becomes difficult to form a continuous conductor pattern of the printed wiring board on the exposure substrate 156. For this reason, as shown in FIG. 21, the digital micromirror device 230 is arranged such that the row of the light beam spot images 260 is slightly inclined (angle θt) with respect to the direction in which the exposure substrate 156 is moved. In FIG. 21, the exposure substrate 156 is moved in the direction indicated by the white arrow. The direction indicated by the white arrow is preferably either the X direction or the Y direction. Here, it is assumed that the exposure substrate 156 is moved in the X direction. Further, the tilting angle θt may be appropriately determined according to the size of the image of the light beam spot formed on the exposure substrate 156 and the interval between the images of the light beam spot.

<Formation of a continuous pattern in the X direction>
FIG. 22 is a diagram illustrating a procedure when forming a pattern continuous in the X direction. 22 (a-1) to 22 (a-4) are diagrams showing the positional relationship between the exposure substrate 156 and the image 260 of the light beam spot, and FIGS. 22 (b-1) to 22 (b-4). ) Is a view showing a portion exposed by moving the exposure substrate 156. 22 (a-1) to 22 (a-4) and 22 (b-1) to 22 (b-4) are also included in the image 260 of the light beam spot formed on the exposure substrate 156. It is a figure which shows a part and a part of exposure board | substrate 156. FIG.

  When a pattern continuous in the X direction is formed, a predetermined one light beam spot image 260a among the plurality of light beam spot images 260 is used. In FIG. 22, this light beam spot image 260a is indicated by a black circle. That is, the light from the light source 210 is irradiated on the exposure substrate 156 only at the light spot image 260a.

As shown in FIG. 22 (a-1), first, the exposure substrate 156 is positioned at a desired position, and an image 260a of one light beam spot is formed on the exposure substrate 156, so as shown in FIG. 22 (b-1). In this manner, one exposure point 262a is formed on the exposure substrate 156.
Next, by moving the exposure substrate 156 by a predetermined distance in the −X direction, and forming an image 260a of the light beam spot on the exposure substrate 156 at that position, as shown in FIG. One exposure point 262b is formed on the exposure substrate 156. The predetermined distance to be moved in the −X direction may be appropriately determined according to the size of the image of the light beam spot formed on the exposure substrate 156 and the interval between the images of the light beam spot.

  Similarly, the exposure substrate 156 is sequentially moved by a predetermined distance in the −X direction, and a light beam spot image 260a is formed on the exposure substrate 156 at that position, whereby FIGS. As shown in (b-4), one exposure point 262c and 262d can be formed on the exposure substrate 156 one after another.

  In this manner, by forming the image 260a of one light beam spot on the exposure substrate 156 while moving the exposure substrate 156 by a predetermined distance in the −X direction, a continuous pattern along the X direction is formed on the exposure substrate 156. Can be formed.

  22 (b-1) to 22 (b-4) described above, the exposure substrate 156 is moved by a certain long distance in order to clearly show the exposure points 262a to 262d formed on the exposure substrate 156. As shown above, the distance by which the exposure substrate 156 is moved may be appropriately determined according to the size of the image of the light beam spot formed on the exposure substrate 156 and the interval of the image of the light beam spot.

<Formation of a continuous pattern in the Y direction>
FIG. 23 is a diagram illustrating a procedure when forming a pattern continuous in the Y direction. 23 (a-1) to 23 (a-3) are diagrams showing the positional relationship between the exposure substrate 156 and the image 260 of the light beam spot, and FIGS. 23 (b-1) to 23 (b-3). ) Is a view showing a portion exposed by moving the exposure substrate 156. 23A-1 to 23A-3 and FIGS. 23B-1 to 23B-3 are also included in the image 260 of the light beam spot formed on the exposure substrate 156. It is a figure which shows a part and a part of exposure board | substrate 156. FIG.

  When a pattern continuous in the Y direction is formed, at least two light beam spot images out of a plurality of light beam spot images 260 are used. FIG. 23 shows an example using three light beam spot images 260a to 260c, which are indicated by black circles. That is, the light from the light source 210 is irradiated on the exposure substrate 156 only at the light beam spot images 260a to 260c.

  As shown in FIG. 23 (a-1), first, the exposure substrate 156 is positioned at a desired position, and an image 260a of one light beam spot is formed on the exposure substrate 156, so as shown in FIG. 23 (b-1). In this manner, one exposure point 264a is formed on the exposure substrate 156.

  Next, the exposure substrate 156 is moved by a predetermined distance in the + X direction. This position is a position where the image 260b of the light beam spot is aligned with the exposure point 264a along the + Y direction. At this position, an image 260b of the light beam spot is formed on the exposure substrate 156, thereby forming one exposure point 264b on the exposure substrate 156 as shown in FIG. 23 (b-2). As described above, the predetermined distance by which the exposure substrate 156 is moved in the + X direction is a distance at which the image of the light beam spot 260b is aligned with the exposure point 264a along the + Y direction.

  Similarly, the exposure substrate 156 is sequentially moved by a predetermined distance in the + X direction, and the image of the light beam spot is formed on the exposure substrate 156 so that the image of the light beam spot is aligned with the exposure point 264a along the + Y direction. Thus, as shown in FIG. 23B-3, one exposure point 264c can be formed on the exposure substrate 156 one after another.

  In this way, by forming the image 260 of two or more light beam spots on the exposure substrate 156 while moving the exposure substrate 156 in the + X direction by a predetermined distance, a pattern continuous along the Y direction is formed on the exposure substrate 156. Can be formed.

  In FIG. 23 (b-1) to FIG. 23 (b-3) described above, the exposure substrate 156 is moved by a certain long distance in order to clearly show the exposure points 264a to 264c formed on the exposure substrate 156. As shown above, the distance by which the exposure substrate 156 is moved is the distance at which the image of the light beam spot is located along the + Y direction.

  In the above-described example, whether the continuous pattern is formed in the X direction or the continuous pattern is formed in the Y direction, the light from the light source 210 is irradiated onto the exposure substrate 156 within a predetermined short time. Although only one of the plurality of light flux spot images 260 is received, the light source 210 emits the light beam 210 so as to form two or more light flux spot images 260 within a predetermined short time. The exposure substrate 156 may be irradiated with light. By doing so, the processing efficiency can be improved, and the time required for pattern formation can be shortened.

  Further, in the projection exposure apparatus 200 shown in FIG. 20, the one composed of one digital micromirror device 230 and one projection lens 150 corresponding thereto is shown, but a plurality of digital micromirror devices and these correspond to these. A plurality of projection lens images 260 may be formed by a plurality of projection lenses within a predetermined short time. In this way, the time required for pattern formation can be further shortened.

<Error occurrence>
As described above, also in the projection exposure apparatus 200 in the second embodiment, the same substrate mounting stage 170 as that in the projection exposure apparatus 100 in the first embodiment is used. Therefore, an error in movement between the X-direction moving stage 172 and the Y-direction moving stage 174 occurs in the same manner as the projection exposure apparatus 100. Abbe errors also occur in the same way.

  Further, the same exposure substrate 156 (156a, 156b and 156c) is used. Therefore, an error in the displacement of the reference mark due to the deformation of the exposure substrate 156 and an error that occurs when the reference mark is formed also occur in the same manner as in the projection exposure apparatus 100.

  For this reason, also in the projection exposure apparatus 200 in the second embodiment, the exposure process by the global method shown in FIG. 9 as described in the first embodiment, or the projection exposure apparatus 200 in FIG. Positioning by using the reference substrate 158a or 158b shown in FIG. 18, exposure processing by the global method using the reference substrate 158a or 158b shown in FIG. 18, and weighting the die-by-die method and the global method shown in FIG. 25, the X direction expansion / contraction Sx is replaced with the X direction difference ΔXM (n), the rotation θ is replaced with the Y direction difference ΔXM (n), and the intelligent global method shown in FIG. Thus, all the processes for determining the position can be performed in the same manner as in the first embodiment.

  Also in the second embodiment described above, the control device 199 causes the first position correction means, the second position correction means, the reference substrate position control means, the reference substrate position storage means, and the reference substrate exposure means. A reference substrate position correction calculation storage means, an exposure substrate position control means, an exposure substrate position storage means, an exposure substrate reference mark position storage means, and a linear error correction calculation means.

1 is a diagram showing an outline of a projection exposure apparatus 100 according to a first embodiment of the present invention. FIG. 2A is a front view showing details of an X direction moving stage 172 and a Y direction moving stage 174, and FIG. 2B is a front view showing details of the X direction moving stage 172; It is a side view which shows the detail of the stage 176 for Z direction movement, and is the thing (a) when the stage 174 for Y direction movement is located in the extreme end part of -Y direction, and the stage 174 for Y direction movement is + Y direction This is (b) when positioned at the end. It is a figure which shows the example of exposure board | substrates 156a and 156b. It is a figure which shows the procedure of the detection of the position of the reference mark by the 1st aspect of the procedure by a die-by-die system, the position adjustment of the exposure board | substrate 156a, and exposure to the exposure board | substrate 156a. It is a figure which shows the procedure of the detection of the position of the reference mark by the 2nd aspect of the procedure by a die-by-die system, the position adjustment of the exposure board | substrate 156a, and exposure to the exposure board | substrate 156b. It is a figure which shows the procedure of the detection of the position of the reference mark by the 3rd aspect of the procedure by a die-by-die system, the position adjustment of the exposure board | substrate 156a, and exposure to the exposure board | substrate 156b. The example of the exposure board | substrate 156c detected in the case of a global system is shown. It is a flowchart which shows the procedure of the process of a global system when using the exposure board | substrate 156c. It is a figure which shows a state when image | photographing the reference mark RM1 and the reference mark RM2 of the exposure area | region of four exposure areas ER1, ER4, ER9, or ER14 of the exposure board | substrate 156c mounted on the table 177. FIG. It is a figure which shows six parameters Sx, Sy, (theta), (omega), Ox, and Oy, and each aspect. It is the front view (a) which shows the outline of the reference board | substrate 158a, and is an enlarged view (b) which shows the reference mark formed in one area | region of the reference board | substrate 158a. It is a figure which shows what uses 18 reference marks among several reference marks about each of 12 area | regions ER1-ER12. It is a flowchart which shows the procedure for determining the position of the reference mark pair of the reference | standard board | substrate 158a. It is the front view (a) which shows the outline of the reference board | substrate 158b, and is an enlarged view (b) which shows the reference mark formed in one area | region of the reference board | substrate 158b. FIG. 6A is a diagram showing a reference pattern formed on a reference position reticle. Reference patterns 158b are transferred to all regions ER1 to ER12 of the reference substrate 158b by the patterns ORM1 to ORM9 corresponding to the uncovered portion 44. FIG. 8B is a diagram (c) illustrating a state where the center is displaced and the patterns ORM1 to ORM9 are transferred. It is a flowchart which shows the procedure of the process which transfers a reference pattern to the reference board | substrate 158b, and the process which determines the position of the reference mark pair of the reference board | substrate 158b. It is a flowchart which shows the procedure which correct | amends the error | error of the movement of the X direction movement stage 172 and the Y direction movement stage 174 using the reference | standard board | substrate 158a or 158b, and performs an exposure process by a global system. It is a flowchart which shows the process which weights a die-by-die system and a global system, and determines the position of the stage 172 for X direction movement, and the stage 174 for Y direction movement. It is a figure which shows the outline of the projection exposure apparatus 100 of 2nd Embodiment which concerns on this invention. It is a figure which expands and shows the image 260 of the light beam spot formed in the exposure board | substrate 156, and the exposure board | substrate 156. FIG. It is a figure which shows the procedure when forming the pattern continuous in a X direction. It is a figure which shows the procedure when forming the pattern continuous in a Y direction. It is a figure which shows the mode of a deformation | transformation of an exposure board | substrate when the deformation | transformation of an exposure board | substrate is approximated by (a) quadratic expression, and (b) is approximated by cubic expression. It is a figure which shows the procedure of the process of an intelligent global system. It is the schematic of an example of the exposure board | substrate used by the process of an intelligent global system. It is the schematic of the exposure board | substrate which shows abbreviate | omitting the detection of some exposure board | substrate reference marks. It is the schematic of the exposure board | substrate which shows abbreviate | omitting the detection of some exposure board | substrate reference marks. It is the schematic which shows an example of a detection area error parameter value. It is the schematic which shows the example of the position error correction | amendment by the process of an intelligent global system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Projection exposure apparatus 110 Light source 142 Reticle 150 Projection lens 156, 156a, 156b, 156c, 156d, 156e, 156f Exposure substrate 158a, 158b Reference substrate 160, 160a, 160b Alignment optical system 162 Image processing device 170 Substrate mounting stage 172 X Direction moving stage 174 Y direction moving stage 176 Z direction moving stage 177 Table (mounting table)
199 Control apparatus 200 Projection exposure apparatus 210 Light source 230 Digital micromirror device RM1, RM2, RM3, RM4 Reference mark ER Exposure area, detection area

Claims (20)

A projection exposure apparatus that irradiates a reticle on which a pattern is formed with exposure light and projects an image of the pattern onto an exposure substrate,
A driving stage for positioning the mounting table on which the substrate is mounted by moving it to at least four predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on a reference substrate capable of exposure;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate reference mark comprises at least four marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least four marks for indicating a reference position of the reference substrate,
The position determining means includes
First position correcting means for correcting an error in the position of the mounting table that occurs when the mounting table is moved;
Second position correcting means for correcting an error of a linear component of errors in the position of the exposure substrate reference mark,
The first position correcting means includes
Reference substrate position control means for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the drive stage when the reference substrate is mounted on the mounting table as the substrate. ,
A reference board position storage means for obtaining and storing the position of the mounting table at each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, exposure light is irradiated onto the reference reticle, and a reticle reference mark formed on the reference reticle is projected onto the reference substrate, thereby forming an image of the reticle reference mark on the reference substrate. A reference substrate exposure means for
The image of the reticle reference mark and the reference substrate reference mark formed on the reference substrate are detected by the reference mark detection means, and the image of the reticle reference mark and the reference substrate reference mark are relative to each other based on the detection result. A reference substrate position correction calculation storage means for calculating a position and calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the relative position and the position of the mounting table; Including
The second position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. Exposure substrate position control means for sequentially moving and positioning the table;
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. Exposure substrate reference mark position storage means for
Linear error correction for calculating linear error correction data for correcting an error of the linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storage means using a least square method A projection exposure apparatus comprising: a calculation means; A projection exposure apparatus that irradiates a reticle on which a pattern is formed with exposure light and projects an image of the pattern onto an exposure substrate,
A driving stage for positioning the mounting table on which the substrate is mounted by moving it to at least four predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate reference mark comprises at least four marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least four marks for indicating a reference position of the reference substrate,
The position determining means includes
First position correcting means for correcting an error in the position of the mounting table that occurs when the mounting table is moved;
Second position correcting means for correcting an error of a linear component of errors in the position of the exposure substrate reference mark,
The first position correcting means includes
Reference substrate position control means for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the drive stage when the reference substrate is mounted on the mounting table as the substrate. ,
A reference board position storage means for obtaining and storing the position of the mounting table at each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, the reference substrate reference mark is detected by the reference mark detection means, and the position of the reference substrate reference mark is calculated and stored based on the detection result and the position of the mounting table. Reference board reference mark position storage means for
Reference substrate position correction calculation storage means for calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the position of the reference substrate reference mark,
The second position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. Exposure substrate position control means for sequentially moving and positioning the table;
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. Exposure substrate reference mark position storage means for
Linear error correction for calculating linear error correction data for correcting an error of the linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storage means using a least square method A projection exposure apparatus comprising: a calculation means; A digital micromirror device having a plurality of mirrors and capable of determining the reflection direction of light incident on the plurality of mirrors for each of the plurality of mirrors, and a plurality of micros each corresponding to each of the plurality of mirrors A projection exposure apparatus that projects an image of a spot formed by the microarray lens onto an exposure substrate.
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on a reference substrate capable of exposure;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
The position determining means includes
First position correcting means for correcting an error in the position of the mounting table that occurs when the mounting table is moved;
Second position correcting means for correcting an error of a linear component of errors in the position of the exposure substrate reference mark,
The first position correcting means includes
Reference substrate position control means for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the drive stage when the reference substrate is mounted on the mounting table as the substrate. ,
A reference board position storage means for obtaining and storing the position of the mounting table at each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, exposure light is irradiated onto the reference reticle, and a reticle reference mark formed on the reference reticle is projected onto the reference substrate, thereby forming an image of the reticle reference mark on the reference substrate. A reference substrate exposure means for
The image of the reticle reference mark and the reference substrate reference mark formed on the reference substrate are detected by the reference mark detection means, and the image of the reticle reference mark and the reference substrate reference mark are relative to each other based on the detection result. A reference substrate position correction calculation storage means for calculating a position and calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the relative position and the position of the mounting table; Including
The second position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. Exposure substrate position control means for sequentially moving and positioning the table;
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. Exposure substrate reference mark position storage means for
Linear error correction for calculating linear error correction data for correcting an error of the linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storage means using a least square method A projection exposure apparatus comprising: a calculation means; A digital micromirror device having a plurality of mirrors and capable of determining the reflection direction of light incident on the plurality of mirrors for each of the plurality of mirrors, and a plurality of micros each corresponding to each of the plurality of mirrors A projection exposure apparatus that projects an image of a spot formed by the microarray lens onto an exposure substrate.
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
The position determining means includes
First position correcting means for correcting an error in the position of the mounting table that occurs when the mounting table is moved;
Second position correcting means for correcting an error of a linear component of errors in the position of the exposure substrate reference mark,
The first position correcting means includes
Reference substrate position control means for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the drive stage when the reference substrate is mounted on the mounting table as the substrate. ,
A reference board position storage means for obtaining and storing the position of the mounting table at each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, the reference substrate reference mark is detected by the reference mark detection means, and the position of the reference substrate reference mark is calculated and stored based on the detection result and the position of the mounting table. Reference board reference mark position storage means for
Reference substrate position correction calculation storage means for calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the position of the reference substrate reference mark,
The second position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. Exposure substrate position control means for sequentially moving and positioning the table;
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. Exposure substrate reference mark position storage means for
Linear error correction for calculating linear error correction data for correcting an error of the linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storage means using a least square method A projection exposure apparatus comprising: a calculation means; A projection optical system that irradiates the exposure substrate with the exposure light;
The reference mark detection means includes an alignment optical system disposed between the projection optical system and the mounting table.
The alignment optical system irradiates the exposure substrate reference mark or the reference substrate reference mark with non-exposure light, and detects the exposure substrate reference mark or the reference substrate reference mark.
The alignment optical system includes:
When detecting the exposure substrate reference mark, or the reference substrate reference mark, is positioned at the detection position,
5. The projection exposure apparatus according to claim 1, wherein when the detection of the exposure substrate reference mark or the reference substrate reference mark is finished, the projection exposure apparatus is positioned at a retracted position retracted from the detection position.   5. The projection exposure apparatus according to claim 1, wherein the mounting table position correction data is calculated based on an average value of the positions of the exposure substrate reference marks at a plurality of reference substrate detection positions. The reference substrate reference mark is formed on the reference substrate so as to be located at a grid-like intersection of predetermined intervals,
The mounting table position correction data is data calculated based on the position of the reference substrate reference mark located at the grid intersection,
The exposure substrate position control means calculates a target position for positioning the mounting table by curve approximation or interpolation using the mounting table position correction data, and controls to position the mounting table at the target position. Projection exposure apparatus in any one of 1-4. A projection optical system capable of projecting the pattern onto the exposure substrate by changing a projection magnification of the image of the pattern;
The projection exposure apparatus according to claim 1, further comprising: a projection magnification determination unit that determines the projection magnification based on the linear error correction data calculated by the linear error correction calculation unit. A projection exposure apparatus that irradiates a reticle on which a pattern is formed with exposure light and projects an image of the pattern onto an exposure substrate,
A driving stage for positioning the mounting table on which the substrate is mounted by moving it to at least four predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate has at least four exposure areas on which an image of the pattern is projected;
The exposure substrate reference mark is an exposure area reference mark indicating a reference position of the at least four exposure areas,
The position determining means includes an exposure position correcting means for correcting an error in the position of the exposure substrate reference mark,
The exposure position correcting means includes
Exposure substrate position control means for sequentially moving and positioning the mounting table to at least four or more predetermined exposure substrate detection positions by the drive stage when the exposure substrate is mounted on the mounting table as the substrate. When,
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure area reference mark, and calculates and stores the position of the exposure area reference mark based on the detection result and the position of the mounting table. Exposure area reference mark position storage means for performing,
Based on the position of the exposure area reference mark stored in the exposure substrate reference mark position storage means, error information of a non-linear component of errors in the position of the exposure substrate reference mark is calculated using a least square method. Position error processing means;
Based on the difference in the position of the exposure area reference mark stored in the exposure substrate reference mark position storage means, the error information of the nonlinear component of the difference in the difference in position of the exposure substrate reference mark is used by the least square method. Differential error processing means for calculating
And an exposure substrate position determining means for calculating a target position for positioning the mounting table by weighting based on at least one error information of the two nonlinear components, and positioning the mounting table at the target position. A projection exposure apparatus. A projection exposure apparatus that irradiates a reticle on which a pattern is formed with exposure light and projects an image of the pattern onto an exposure substrate,
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
Reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
The exposure substrate has at least three exposure areas on which an image of the pattern is projected;
The exposure substrate reference mark is an exposure area reference mark indicating a reference position of the at least three exposure areas,
The position determining means includes an exposure position correcting means for correcting an error in the position of the exposure substrate reference mark,
The exposure position correcting means includes
When the exposure substrate is placed on the mounting table as the substrate, exposure substrate position control means for sequentially moving the mounting table to at least three or more predetermined exposure substrate detection positions by the drive stage. When,
Exposure substrate position storage means for acquiring and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure area reference mark, and calculates and stores the position of the exposure area reference mark based on the detection result and the position of the mounting table. Exposure area reference mark position storage means for performing,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure area reference mark stored in the exposure area reference mark position storage means using a least square method Means,
Difference calculating means for calculating a difference between the positions of the exposure area reference marks stored in the exposure substrate reference mark position storage means;
Replacing at least one of expansion / contraction, rotation and orthogonality obtained by the least square method with the difference, irradiating the reticle with exposure light, and projecting an image of the pattern onto an exposure substrate; and A projection exposure apparatus comprising: an overlay control unit that calculates and controls an overlay target position with the exposure substrate. A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on a reference substrate capable of exposure;
A projection exposure apparatus including a position determining unit for determining the position of the mounting table based on the position indicated by the position signal, and irradiating the reticle on which the pattern is formed with exposure light, A projection exposure method for projecting an image of the pattern onto the exposure substrate placed on a mounting table,
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
A reference substrate position control step for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the driving stage when the reference substrate is mounted on the mounting table as the substrate; ,
A reference substrate position storing step for obtaining and storing the position of the mounting table in each of the reference substrate detection positions from the position signal;
At each of the reference substrate detection positions, exposure light is irradiated onto the reference reticle, and a reticle reference mark formed on the reference reticle is projected onto the reference substrate, thereby forming an image of the reticle reference mark on the reference substrate. A reference substrate exposure step,
The image of the reticle reference mark and the reference substrate reference mark formed on the reference substrate are detected by the reference mark detection means, and the image of the reticle reference mark and the reference substrate reference mark are relative to each other based on the detection result. A reference substrate position correction calculation storage step for calculating a position and calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the relative position and the position of the mounting table;
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. An exposure substrate position control step for sequentially moving and positioning the mounting table;
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. An exposure substrate reference mark position storing step,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storing step using a least square method A projection exposure method comprising the steps of: A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
A projection exposure apparatus including a position determining unit for determining the position of the mounting table based on the position indicated by the position signal, and irradiating the reticle on which the pattern is formed with exposure light, A projection exposure method for projecting an image of the pattern onto the exposure substrate placed on a mounting table,
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
A reference substrate position control step for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the driving stage when the reference substrate is mounted on the mounting table as the substrate; ,
A reference board position storing step for obtaining and storing the position of the mounting table in each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, the reference substrate reference mark is detected by the reference mark detection means, and the position of the reference substrate reference mark is calculated and stored based on the detection result and the position of the mounting table. A reference board reference mark position storing step,
A reference substrate position correction calculation storage step for calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the position of the reference substrate reference mark;
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. An exposure substrate position control step for sequentially moving and positioning the mounting table;
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. An exposure substrate reference mark position storing step,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storing step using a least square method A projection exposure method comprising the steps of: A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on a reference substrate capable of exposure;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
A digital micromirror device having a plurality of mirrors and capable of determining the reflection direction of light incident on the plurality of mirrors for each of the plurality of mirrors;
The image of the spot formed by the microarray lens was placed on the mounting table using a projection exposure apparatus including a microarray lens having a plurality of microlenses corresponding to each of the plurality of mirrors. A projection exposure method for projecting onto the exposure substrate,
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
A reference substrate position control step for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the driving stage when the reference substrate is mounted on the mounting table as the substrate; ,
A reference board position storing step for obtaining and storing the position of the mounting table in each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, exposure light is irradiated onto the reference reticle, and a reticle reference mark formed on the reference reticle is projected onto the reference substrate, thereby forming an image of the reticle reference mark on the reference substrate. A reference substrate exposure step,
The image of the reticle reference mark and the reference substrate reference mark formed on the reference substrate are detected by the reference mark detection means, and the image of the reticle reference mark and the reference substrate reference mark are relative to each other based on the detection result. A reference substrate position correction calculation storage step for calculating a position and calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the relative position and the position of the mounting table;
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. An exposure substrate position control step for sequentially moving and positioning the mounting table;
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. An exposure substrate reference mark position storing step,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storing step using a least square method A projection exposure method comprising the steps of: A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
Position determining means for determining the position of the mounting table based on the position indicated by the position signal;
A digital micromirror device having a plurality of mirrors and capable of determining the reflection direction of light incident on the plurality of mirrors for each of the plurality of mirrors;
The image of the spot formed by the microarray lens was placed on the mounting table using a projection exposure apparatus including a microarray lens having a plurality of microlenses corresponding to each of the plurality of mirrors. A projection exposure method for projecting onto the exposure substrate,
The exposure substrate reference mark comprises at least three marks for indicating a reference position of the exposure substrate,
The reference substrate reference mark includes at least three marks for indicating a reference position of the reference substrate,
A reference substrate position control step for sequentially moving and positioning the mounting table to at least three or more predetermined reference substrate detection positions by the driving stage when the reference substrate is mounted on the mounting table as the substrate; ,
A reference board position storing step for obtaining and storing the position of the mounting table in each of the reference board detection positions from the position signal;
At each of the reference substrate detection positions, the reference substrate reference mark is detected by the reference mark detection means, and the position of the reference substrate reference mark is calculated and stored based on the detection result and the position of the mounting table. A reference board reference mark position storing step,
A reference substrate position correction calculation storage step for calculating and storing mounting table position correction data for correcting an error in the position of the mounting table based on the position of the reference substrate reference mark;
When the exposure substrate is placed on the mounting table as the substrate, the driving stage sets at least three or more predetermined exposure substrate detection positions determined based on the mounting table position correction data. An exposure substrate position control step for sequentially moving and positioning the mounting table;
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure substrate reference mark, and calculates and stores the position of the exposure substrate reference mark based on the detection result and the position of the mounting table. An exposure substrate reference mark position storing step,
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure substrate reference mark stored in the exposure substrate reference mark position storing step using a least square method A projection exposure method comprising the steps of: The projection exposure apparatus includes a projection optical system that irradiates the exposure substrate with the exposure light,
The reference mark detection means is disposed between the projection optical system and the mounting table, and irradiates the exposure substrate reference mark or the reference substrate reference mark with non-exposure light, and the exposure substrate reference mark, or An alignment optical system for detecting the reference substrate reference mark,
When detecting the reference substrate reference mark or the exposure substrate reference mark by the reference mark detection means,
When detecting the exposure substrate reference mark or the reference substrate reference mark, positioning the alignment optical system at a detection position;
15. When the detection of the exposure substrate reference mark or the reference substrate reference mark is completed, the alignment optical system is positioned at a retracted position retracted from the detection position. Projection exposure method.   The projection exposure method according to claim 11, wherein the mounting table position correction data is calculated based on an average value of positions of the exposure substrate reference marks at a plurality of reference substrate detection positions. The reference substrate reference mark is formed on the reference substrate so as to be located at a grid-like intersection of predetermined intervals,
The mounting table position correction data is data calculated based on the position of the reference substrate reference mark located at the grid intersection,
15. The method according to claim 11, further comprising: calculating a target position for positioning the mounting table by using a curve approximation or interpolation method using the mounting table position correction data, and controlling the positioning to position the mounting table at the target position. A projection exposure method according to claim 1. A projection optical system capable of changing the projection magnification of the image of the pattern and projecting the pattern onto the exposure substrate;
The projection exposure method according to claim 11, further comprising a step of determining the projection magnification based on the linear error correction data calculated in the linear error correction calculation step. A driving stage for positioning the mounting table on which the substrate is mounted by moving it to at least four predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
A projection exposure apparatus including a position determining unit for determining the position of the mounting table based on the position indicated by the position signal, and irradiating the reticle on which the pattern is formed with exposure light, A projection exposure method for projecting an image of the pattern onto the exposure substrate placed on a mounting table,
The exposure substrate has at least four exposure areas on which an image of the pattern is projected;
The exposure substrate reference mark is an exposure area reference mark indicating a reference position of the at least four exposure areas,
An exposure substrate position control step of sequentially moving and positioning the mounting table to at least four or more predetermined exposure substrate detection positions by the drive stage when the exposure substrate is mounted on the mounting table as the substrate. When,
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure area reference mark, and calculates and stores the position of the exposure area reference mark based on the detection result and the position of the mounting table. An exposure area reference mark position storing step;
Based on the position of the exposure area reference mark stored in the exposure substrate reference mark position storing step, error information of a non-linear component of errors in the position of the exposure substrate reference mark is calculated using a least square method. A position error processing step;
Based on the difference in the position of the exposure area reference mark stored in the exposure substrate reference mark position storage means, the error information of the non-linear component of the difference in the difference in position of the exposure substrate reference mark is used by the least square method. Differential error processing step to calculate,
A step of calculating a target position for positioning the mounting table by weighting based on error information of at least one of the two nonlinear components, and determining an exposure substrate position for positioning the mounting table at the target position. A characteristic projection exposure method. A projection exposure method of irradiating a reticle on which a pattern is formed with exposure light and projecting an image of the pattern onto an exposure substrate,
A drive stage for positioning the mounting table on which the substrate is mounted by moving it to at least three predetermined positions;
Position signal output means provided on the drive stage and outputting a position signal indicating the position of the mounting table,
A reference mark detection means for detecting an exposure substrate reference mark formed on the exposure substrate or a reference substrate reference mark formed on the reference substrate;
A projection exposure apparatus including a position determining unit for determining the position of the mounting table based on the position indicated by the position signal, and irradiating the reticle on which the pattern is formed with exposure light, A projection exposure method for projecting an image of the pattern onto the exposure substrate placed on a mounting table,
The exposure substrate has at least three exposure areas on which an image of the pattern is projected;
The exposure substrate reference mark is an exposure area reference mark indicating a reference position of the at least three exposure areas,
An exposure substrate position control step for sequentially moving and positioning the mounting table to at least three predetermined exposure substrate detection positions by the drive stage when the exposure substrate is mounted on the mounting table as the substrate. When,
An exposure substrate position storing step for obtaining and storing the position of the mounting table at each of the exposure substrate detection positions from the position signal;
At each of the exposure substrate detection positions, the reference mark detection means detects the exposure area reference mark, and calculates and stores the position of the exposure area reference mark based on the detection result and the position of the mounting table. An exposure area reference mark position storing step;
Linear error correction calculation for calculating linear error correction data for correcting an error of a linear component based on the position of the exposure area reference mark stored in the exposure area reference mark position storage means using a least square method Steps,
A difference calculating step of calculating a difference between the positions of the exposure area reference marks stored in the exposure substrate reference mark position storing step;
Replacing at least one of expansion / contraction, rotation and orthogonality obtained by the least square method with the difference, irradiating the reticle with exposure light, and projecting an image of the pattern onto an exposure substrate; and A projection exposure method comprising: an overlay control step of calculating and controlling an overlay target position with the exposure substrate.

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