JP2002141276A - Aligner and its method, method for manufacturing thereof, manufacturing plant of semiconductor and maintaining method for the exposure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically set measuring conditions that have been conventionally made manually, thus to reduce the load on users of an aligner. SOLUTION: This aligner is for projecting and exposing a pattern on an original plate onto a photosensitive board, that is mounted on a mobile stage by way of the projection optical system. The condition for projecting and exposing is decided by referencing at least one piece of information, that is selected from the reticle information about the pattern on the original plate and the ground baking information about the pattern that has already been baked on the photosensitive board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection exposure apparatus and a projection exposure method for manufacturing semiconductor circuit elements such as ICs, LSIs and VLSIs, and a device manufacturing method using the same.
The present invention relates to a semiconductor manufacturing factory and a method of maintaining an exposure apparatus, particularly in a field of manufacturing semiconductor circuit elements (devices), an automatic focus adjustment function when repeatedly projecting and exposing a reticle circuit pattern on a semiconductor wafer surface, a so-called auto focus function, and an overlay function The present invention relates to a semiconductor exposure apparatus and method having an automatic measurement function of alignment accuracy, so-called alignment function.

[0002]

2. Description of the Related Art Conventionally, at the time of alignment measurement of an exposure apparatus, setting of measurement conditions (measurement position, measurement mark, etc.) is judged by a user of the apparatus from data at the time of reticle design, and manually set as wafer exposure conditions. I was At the time of alignment measurement, the measurement is performed according to the measurement conditions included in the preset wafer exposure conditions.

In the autofocus measurement of the exposure apparatus, setting of measurement conditions (measurement position, measurement field of view, correction method of measurement value, measurement execution timing, measurement mark, etc.) is performed by a user of the apparatus by using data or reticle design data. Judgment was made based on the exposure conditions, and the wafer exposure conditions were set manually. Then, at the time of the autofocus measurement, the measurement is performed according to the measurement condition included in the preset wafer exposure condition.

[0004]

In recent years, semiconductor devices such as L
Due to the demand for finer patterns and higher integration of SI elements, VLSI elements, and the like, a projection (exposure) exposure apparatus requires an imaging (projection) optical system having high resolution. With this, the NA of the imaging optical system has been increased, and as a result, the depth of focus of the imaging optical system has become smaller. Therefore, the exposure apparatus is required to have high measurement accuracy and performance.

On the other hand, in order to satisfy such demands, as a result of sequentially adding functions and improving the accuracy, setting items for measurement increase and a setting pattern may become complicated. Was. As setting patterns have become more complicated, the number of items that the user of the apparatus must set in order to perform alignment measurement and autofocus measurement has increased, resulting in a burden on the user.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned problems of the prior art, and to make it possible to automatically set measurement conditions which have been manually entered so far, thereby reducing the burden on an exposure apparatus user. Aim.

[0007]

According to the present invention, there is provided an exposure apparatus for projecting and exposing a pattern on an original onto a photosensitive substrate mounted on a movable stage via a projection optical system. Measuring condition determining means for determining a measuring condition when performing projection exposure with reference to at least one information selected from reticle information on a pattern on an original plate and underlay printing information on a pattern already printed on a photosensitive substrate. It is characterized by having.

Normally, the measurement condition determining means is selected from base printing information, reticle information, and wafer exposure conditions preset for this exposure processing when providing a plurality of layers by repeatedly exposing the photosensitive substrate. At least one
Based on the two pieces of information, measurement conditions for performing autofocus measurement and / or alignment measurement of the photosensitive substrate are determined.

Underlay printing information is usually stored in a table format for each layer. For example, the shape, position, size, printing direction and line width of each pattern printed as a background, and the background exposure time And information such as an alignment measurement value, an exposure apparatus type, and an exposure size. The alignment measurement value indicates a measurement result when the alignment measurement is performed, and usually includes a measured shift amount and a difference between the reference offset and the device-specific offset.

It is desirable that the underprinting information can be updated by an exposure apparatus that has performed exposure or alignment measurement.

The reticle information is usually stored in the form of a table for each original plate, and includes the shape, position, size, and line width of the pattern at the time of the original plate design, as well as an identifier for identifying the original plate and a focal position. Contains information.

The base printing information and / or reticle information is transmitted / received to / from another exposure apparatus or computer equipment connected to a network line, so that a plurality of exposure apparatuses can process one wafer. It is possible to cope with a so-called “mix and match” in which an exposure process is performed on the image data. Further, even if such information is stored in a portable storage medium, the information can be shared between the exposure apparatuses.

Further, even if the exposure apparatus of the present invention is provided with a display, a network interface, and a computer for executing network software, the maintenance information of the exposure apparatus including the base printing information and the reticle information can be transferred to a computer network. It is possible to perform data communication via. The network software is connected to an external network of the factory where the exposure apparatus is installed, and provides a user interface on a display for accessing a maintenance database provided by an exposure apparatus vendor or a user. To obtain information from the database.

The measurement condition determination means usually determines a measurement mark and a mark measurement position to be used for alignment measurement from a plurality of measurement marks provided on the photosensitive substrate at the time of alignment measurement, and at the time of autofocus measurement. , A measurement mark used for autofocus measurement, a measurement visual field, a measurement position, a measurement execution timing, and a method of correcting a measurement value are determined. In particular, it is desirable that the measurement execution timing at the time of the autofocus measurement is determined by the wafer exposure condition, and the correction method of the measurement value at the time of the autofocus measurement is determined by the wafer exposure condition and the measurement position.

Further, according to the exposure method of the present invention, there is provided a photosensitive substrate in which a pattern on an original plate is mounted on a movable stage via a projection optical system by using an apparatus having a configuration like the above-described exposure apparatus of the present invention. An exposure method for projecting and exposing an image on a substrate, wherein the projection exposure is performed with reference to at least one information selected from reticle information on a pattern on an original plate and base printing information on a pattern already printed on a photosensitive substrate. And a measuring condition determining step of determining the above condition.

Further, according to the present invention, a measurement reference point formed on a photosensitive substrate is detected, and exposure is performed based on the measurement reference point.
A recording medium which records a program for executing alignment measurement of the projection exposure apparatus of the present invention, wherein the semiconductor chip is formed in each region on a photosensitive substrate, wherein the program determines a mark measurement position at the time of alignment measurement. First determined based on at least one information selected from underlay printing information, reticle information and wafer exposure conditions
And a second step of determining a measurement mark at the time of alignment measurement based on at least one information selected from base printing information, reticle information and wafer exposure conditions.

According to the present invention, there is provided a recording medium storing a program for executing an autofocus measurement of the projection exposure apparatus of the present invention for detecting an optimum focus position on a photosensitive substrate surface and performing exposure based on the optimum focus position. The program determines a measurement execution timing at the time of autofocus measurement according to the wafer exposure condition, and sets the mark measurement position at the time of autofocus measurement to at least one of base printing information, reticle information, and wafer exposure condition. The second step, which is determined based on the above information, sets the measurement visual field at the time of the autofocus measurement to the background printing information, the reticle information,
A third step of determining at least one or more pieces of information among the wafer exposure conditions; and a third step of determining a measurement mark at the time of autofocus measurement from at least one piece of information among underprinting information, reticle information, and wafer exposure conditions. 4
Step and the fifth method of determining the method of correcting the measurement value at the time of autofocus measurement based on the measurement position and the wafer exposure condition.
Step.

Further, the device manufacturing method of the present invention includes a step of installing a group of manufacturing apparatuses for various processes including the above-described exposure apparatus of the present invention in a semiconductor manufacturing factory, and a step of using a plurality of processes by using the group of manufacturing apparatuses. Manufacturing a device. The method further includes a step of connecting the manufacturing apparatus group with a local area network, and a step of performing data communication of information on at least one of the manufacturing apparatus group between the local area network and an external network outside the semiconductor manufacturing factory. Is also good. Also, a database provided by an exposure apparatus vendor or user is accessed via an external network to obtain maintenance information of the manufacturing apparatus by data communication, or an external network is connected to a semiconductor manufacturing factory different from a semiconductor manufacturing factory. The production management may be performed by data communication via the PC.

Further, a semiconductor manufacturing plant of the present invention comprises a group of manufacturing apparatuses for various processes including the exposure apparatus of the present invention,
A local area network connecting the group of manufacturing apparatuses, and a gateway that enables the local area network to access an external network outside the factory;
This enables data communication of information on at least one of the manufacturing apparatus groups.

Further, according to the exposure apparatus maintenance method of the present invention, the exposure apparatus vendor or the user provides a maintenance database connected to an external network of the semiconductor manufacturing plant, and a step of providing the maintenance database from within the semiconductor manufacturing plant via the external network. And a step of transmitting maintenance information stored in the maintenance database to the semiconductor manufacturing factory via an external network.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below. In a preferred embodiment of the present invention, measurement conditions for alignment measurement are as follows: The measurement marks for the alignment measurement include (a) the pattern shape of the underlayer printing information, (b) the pattern shape of the reticle information, (c) the arrangement of the exposure shots under the wafer exposure conditions, (d) the exposure shot size under the wafer exposure conditions, and ( E) Automatic determination based on at least one information selected from the alignment measurement mark setting of wafer exposure conditions. 2. The mark measurement positions for the alignment measurement are as follows: (a) the pattern shape of the base printing information, (b) the pattern position of the base printing information, (c) the pattern shape of the reticle information, (d) the pattern position of the reticle information, and (e) It is automatically determined from at least one information selected from: (1) exposure shot arrangement of wafer exposure conditions, (2) exposure shot size of wafer exposure conditions, and (4) alignment mark measurement position setting of wafer exposure conditions.

The measurement conditions for the autofocus measurement are as follows: The measurement execution timing of the auto focus measurement is set as follows: (a) the number of processed wafers under the wafer exposure conditions, (b) the exposure amount under the wafer exposure conditions, (c) the number of exposure shots under the wafer exposure conditions, and (d) the setting of the wafer exposure conditions. It is automatically determined by at least one information selected from the values. 2. The measurement marks for the autofocus measurement are as follows: (a) the pattern shape of the base printing information, (b) the pattern line width of the base printing information, (c) the pattern shape of the reticle information, (iv) the pattern line width of the reticle information, This is automatically determined from at least one information selected from the following: exposure conditions of the wafer exposure conditions, exposure shot size of the wafer exposure conditions, and autofocus measurement mark setting of the wafer exposure conditions. 3. The measurement field of view of the autofocus measurement is as follows: (a) the pattern shape of the base printing information, (b) the pattern position of the base printing information, (c) the pattern shape of the reticle information, (d) the pattern position of the reticle information, and (e) the wafer. It is automatically determined from at least one information selected from the exposure shot size of the exposure condition and the setting of the autofocus measurement visual field of the wafer exposure condition. 4. The measurement positions of the autofocus measurement are as follows: (a) the pattern shape of the background printing information, (b) the pattern position of the background printing information, (c) the pattern line width of the background printing information, (d) the pattern shape of the reticle information, and (e) ) Pattern position of reticle information, (f) pattern line width of reticle information, (g) illumination condition at the time of wafer exposure condition, (h) exposure shot size of wafer exposure condition, and (iii) auto of wafer exposure condition Automatically determined from at least one piece of information selected from the focus measurement position setting. 5. The measurement value correction method of the autofocus measurement is as follows: (a) the pattern position of the background printing information, (b) the pattern position of the reticle information, (c) the illumination condition at the time of the wafer exposure condition, and (d) the wafer exposure condition. Automatically determined based on at least one information selected from the exposure shot size and (e) measurement value correction setting of wafer exposure conditions. As a result, automatic determination of measurement conditions is realized.

The underlay printing information indicates information on a pattern already printed on the wafer at the time of the overlay exposure, and is usually in units of layers: pattern shape, pattern size, pattern position, exposure It has the following information: device type, exposure direction, reticle identifier, and alignment measurement value.

In the embodiment of the present invention, attention is paid to a measurement mark printed on a base as a pattern shape, and the pattern is expressed for the purpose of measurement (for pre-alignment, auto focus, etc.). Also, the size of the pattern
The size and pattern position of each measurement mark are represented by the absolute coordinate position on the wafer, the exposure device type is represented by the type of exposure device (stepper, scanner, etc.) used for each layer, and the direction at the time of exposure is represented by a stepper. When the exposure is performed by the scanner, the step direction before the exposure is expressed, and when the exposure is performed by the scanner, the scan direction is expressed. However, the pattern position may be a relative coordinate position instead of an absolute coordinate position.

The reticle identifier only needs to be able to identify which reticle is the reticle used when exposing the layer printed on the base.
It may be the same as the “identifier” included in the reticle information as described later. "Identifier" included in reticle information
When the “identifier” included in the underprinting information and the “identifier” included in the underprinting information are handled as the same identifier, the underprinting information and the reticle information can be handled simultaneously in the exposure apparatus.

In addition, regarding the alignment measurement value, in order to cope with a so-called “mix and match” in which a plurality of exposure apparatuses are provided and one wafer is subjected to exposure processing by a plurality of exposure apparatuses, a host apparatus is required. A computer or the like manages device-specific offsets of a plurality of exposure devices, sets a reference offset, obtains a difference between device-specific offsets of each exposure device from the reference offset, and manages the difference as an alignment measurement value. Further, when the alignment measurement is performed in each device, the measurement is performed with the position obtained by adding the difference from the reference offset to the offset unique to the device as the origin, and the deviation amount from the origin is managed as the alignment measurement value.

FIG. 1 shows the relationship between the “difference from the reference offset” and the “shift amount” included in the alignment measurement value. In FIG. 1, the device 1 is shown on the left, the reference offset is shown in the middle, and the device 2 is shown on the right. The device-specific offset in FIG. 1 indicates the offset amount held by the device 1 and the device 2 as the device offset.

The difference from the reference offset in FIG. 1 indicates the difference between the reference offset and the offset unique to the apparatus. The deviation amount in FIG. 1 represents a measured value measured by alignment measurement when a position obtained by adding a difference from a reference offset to a device-specific offset is used as an origin in each device. As a result, the deviation amount in the alignment measurement value can be used in common among a plurality of apparatuses. The reference offset may be managed by the host computer as described above, or may be managed by the exposure apparatus. When the exposure apparatus manages the reference offset, it is not necessary to manage the difference from the reference offset in the base printing information.

Each exposure apparatus that has printed a base creates base printing information and transfers it to a host computer or the like via a network or the like, so that the host computer manages all base printing information for one wafer. Becomes possible. Further, by transferring the data from a host computer or the like via a network or the like, it is possible to provide the exposure apparatus with all the underlying printing information for the wafer to be exposed. The underlayer printing information may be created for each wafer, or data may be created from an average value of all data of wafers processed in process units.

The reticle information is based on CAD data or the like at the time of reticle design, and includes information such as an identifier (reticle ID), a pattern shape, a pattern position, a pattern size, a pattern line width, and a focal position. I have.

In the embodiment of the present invention, the identifier is represented as a reticle ID for identifying a plurality of pieces of reticle information.
It is desirable that the reticle information be managed by the host computer. In this case, the reticle information can be transferred from the host computer to the exposure apparatus via a network or the like before the exposure processing. Of course, the reticle information can be stored in a storage medium such as an FD, an MO, and a CD-ROM, and can be read by an exposure apparatus.

In the embodiment of the present invention, when the measurement conditions of the alignment measurement and the auto-focus measurement are automatically determined on the basis of the following conditions: Determines measurement conditions based on the parameters of "alignment measurement mark setting", "alignment measurement mark position setting", "alignment measurement shot setting", "autofocus measurement mark setting", "autofocus measurement mark position setting", and "autofocus measurement visual field setting" You may.

In the present invention, information on the marks on the reticle reference plate and the stage reference plate (mark shape, mark line width, mark position, mark size, mark type, focus position) is usually stored in advance. Registered in the device. At the time of measurement (so-called TTR measurement) through the reticle or reticle reference plate, the focal position of the observation scope with respect to the reticle surface is adjusted by reading out and driving the reticle information or the “focal position” of the reticle reference plate. The focal position of the wafer stage surface at the time of the alignment measurement is adjusted by reading the printing information of the base or the “focal position” of the stage reference plate and driving the same. At the time of the autofocus measurement, the printing information of the base or the “focal position” of the stage reference plate is read, and the shift of the focal position is measured. Table 1
The "size" (exposure shot size) is described as "22 * 22" in the printing information of the base under "shot size", but it may be the position of the "aperture stop" at the time of exposure.

<Embodiment 1> In this embodiment, a description will be given of a measurement condition determining means for automatically determining a measurement condition at the time of alignment measurement based on base printing information. The exposure apparatus according to the first embodiment stores in advance the underprinting information when a wafer is exposed in a format as shown in Table 1.

[0035]

[Table 1]

For alignment measurement, it is necessary to select a measurement mark and to determine the coordinates of the measurement mark.

Measurement marks are selected based on the “pattern shape” included in the background printing information. When performing pre-alignment, the pattern shape in Table 1 is marked with “PA” (“PA” mark), and when performing global alignment, the pattern shape in Table 1 is changed to “W”.
Marks “X” or “WY” (“WX” and “WY” marks) are selected, respectively.

Next, the position of the measurement mark is selected based on the "pattern position" included in the background printing information. As the selection criterion, “a pattern position as far as possible outside” may be selected, or “selection by printing direction” may be selected based on “direction” included in the background printing information. FIG. 2 shows an image diagram in which alignment marks are arranged on the wafer based on the underlay printing information. In FIG. 2, a large circle represents a wafer, and a black square (■) represents “P” for pre-alignment.
The “A” mark and the open squares (□) represent the “WX” and “WY” marks for global alignment. According to the present embodiment, it is not necessary for the operator to set various measurement marks and their coordinates at the time of the overlay exposure.

<Embodiment 2> In the present embodiment, a description will be given of a measurement condition determining means for automatically determining measurement conditions at the time of alignment measurement based on underprinting information and exposure shot arrangement of wafer exposure conditions. The exposure apparatus according to the second embodiment stores base printing information when a wafer is exposed in advance.
Is stored in a format as shown in FIG.

FIG. 2 shows a wafer image based on the underlay printing information, as in the first embodiment. FIGS. 3, 4, and 5 are image diagrams in which the exposure shot arrangement of the wafer exposure condition is superimposed on the base printing information. FIG. 3 shows a case where one exposure shot (one shot is exposed for one base shot) is set for one set of “PA” mark for pre-alignment and “WX” and “WY” marks for global alignment. It is an image figure.

As in the first embodiment, the selection of the measurement marks in the present embodiment is made based on the “pattern shape” included in the background printing information. When the pre-alignment is performed, the mark whose pattern shape is indicated by “PA” in Table 1 is used. When the global alignment is performed, the mark whose pattern shape is indicated by “WX” or “WY” is used. Is selected.

Next, the position of the measurement mark may be selected based on the “pattern position” included in the background printing information,
From the “exposure shot arrangement” specified by the wafer exposure conditions, the position of the “PA” mark in shot 1 in FIG. 3 is used as the measurement mark position in pre-alignment, and the “WX” “ WY "
The position of the mark may be used as the position of the measurement mark. In addition,
There is no particular limitation on a method for determining a shot for which alignment measurement is to be performed based on the arrangement of exposure shots under wafer exposure conditions.

FIG. 4 shows one exposure shot for two sets of a "PA" mark for pre-alignment and "WX" and "WY" marks for global alignment (one shot is exposed for two base shots). FIG. 7 is an image diagram when “” is set.

As in the first embodiment, when selecting a measurement mark based on the “pattern shape” included in the background printing information, when performing pre-alignment, the pattern shape in Table 1 is set to “PA”. When the global alignment is performed, a mark whose pattern shape is indicated by “WX” or “WY” in Table 1 is selected.

When a measurement mark is selected from the “print direction” included in the base printing information, for example, when the base printing is performed by a scanning type exposure apparatus,
There is a case where the direction of printing of the base is reversed in one shot area to be printed from now on (a shot printed in the upward direction and a shot printed in the downward direction are mixed).

In such a case, the selection of the pre-alignment “PA” mark is specified by the wafer exposure condition.
When two "PA" marks existing in a shot are set, the "PA" mark for pre-alignment of the base printed in the upward direction and the pre-alignment of the base printed in the downward direction in one shot pre-alignment measurement "P
With the "A" mark, it is possible to obtain a measured value for each printing direction.

On the other hand, when the selection of the pre-alignment “PA” mark is set to one of the two “PA” marks existing in one shot specified by the wafer exposure condition, the printing direction is upward. It is possible to select only the “PA” mark, the “PA” mark with the burning direction down, or the “PA” mark with the burning direction up and down. Become.

Similarly, “W
When the X and WY marks are also set to two sets of “WX” and “WY” marks existing in one shot of the wafer exposure condition, the base of the base printed in the upward direction by one shot global alignment measurement is set. It is possible to obtain a measurement value for each printing direction by using the global alignment “WX” and “WY” marks and the global alignment “WX” and “WY” marks printed in the lower direction.

On the other hand, “WX” and “WY” marks for global alignment are selected by two sets of “WX” and “W” existing in one shot specified by the wafer exposure conditions.
When set to either of the “Y” marks, you can select only the mark with the burning direction up, the mark with the burning direction down, or the mark with the burning direction up and down. Can be selected together.

Next, the position of the measurement mark may be selected based on the “pattern position” included in the background printing information,
From the exposure shot arrangement under the wafer exposure conditions, the position of the “PA” mark in shot 3 is set as the measurement mark position during pre-alignment, and the position of the “WX” and “WY” marks in shot 4 is set as the measurement mark during global alignment. The position should be.

FIG. 5 shows one exposure shot (one shot is exposed for four base shots) for four sets of “PA” marks for pre-alignment and “WX” and “WY” marks for global alignment. It is an image figure in the case of having done.

When selecting the measurement marks by the “pattern shape” included in the background printing information as in the first embodiment, when performing pre-alignment, the pattern shape in Table 1 is set to “PA”. When the global alignment is performed, a mark whose pattern shape is indicated by “WX” or “WY” in Table 1 is selected.

When the measurement mark is selected from the “print direction” included in the base printing information, for example, when the base printing is performed by a scanning type exposure apparatus,
There is a case where the direction of printing of the base is reversed in one shot area to be printed from now on (a shot printed in the upward direction and a shot printed in the downward direction are mixed).

In such a case, when the selection of the pre-alignment mark is set to four “PA” marks existing in one shot specified by the wafer exposure condition,
In the pre-alignment measurement of one shot, it is possible to obtain a measurement value for each printing direction by using the pre-alignment mark of the base printed in the upward direction and the “PA” mark for pre-alignment of the base printed in the downward direction.

The pre-alignment “PA” mark is selected from among four “PA” marks existing in one shot specified by the wafer exposure conditions, one mark obtained by printing the base in the upward direction, and one mark obtained in the downward direction. When one mark printed in step (1) is selected, it is possible to obtain the measurement values for the upward and downward marks of the printing of the base by pre-alignment measurement of one shot.

Further, when only one of the four “PA” marks existing in one shot specified by the wafer exposure condition is selected for measurement, the “printing direction of base is upward The following three patterns can be selected: "only the mark of the mark", "only the mark where the background printing direction is downward", and "the mixture of the background printing direction in the vertical direction".

Similarly, when the selection of the global alignment mark is set to four sets of “WX” and “WY” marks existing in one shot specified by the wafer exposure condition, the global alignment measurement of one shot is performed. It is possible to obtain a measurement value for each printing direction using the base global alignment mark printed in the upward direction and the base global alignment mark printed in the downward direction.

"WX""W" for global alignment
The "Y" mark was selected from among four sets of marks existing in one shot specified by the wafer exposure condition, one mark where the base was baked upward and one mark where the base was baked downward. In this case, it is possible to obtain a measurement value for the mark in the vertical direction of the printing of the base by one-shot global alignment measurement.

Further, when it is selected that only one set of marks is to be measured out of four sets of “WX” and “WY” marks existing in one shot specified by the wafer exposure conditions, Only the printing direction is upward. "
It is possible to select three patterns of “the base printing direction is only downward” and “the base printing direction is mixed in the vertical direction”.

<Embodiment 3> In the exposure apparatus of this embodiment, reticle information used for wafer exposure is stored in advance in a format as shown in Table 2.

[0061]

[Table 2]

In the present embodiment, a description will be given of a measurement condition determining means for automatically determining measurement conditions at the time of autofocus measurement from reticle information. For autofocus measurement, it is necessary to select a measurement mark, select a measurement position, and select a measurement field of view. The measurement mark can be selected using the “pattern shape” and “pattern line width” included in the reticle information or the “mark shape” and “mark line width” on the reticle reference plate.
Sort by. When performing autofocus measurement through a mark on the reticle, a mark in which the pattern shape in Table 2 is “FOCUS” (“FOCUS” mark)
Is selected. When performing autofocus measurement through a mark on the reticle reference plate, a “FOCUS” mark on the reticle reference plate is selected.

In this case, it is desirable to select a “FOCUS” mark having the same line width or the closest line width as the “pattern line width” of the pattern actually printed in the “pattern shape” of the reticle information.

Next, the measurement position is selected based on the “pattern position” included in the reticle information or the “mark position” of the reticle reference plate. As for the sorting criterion, for the reticle, the outermost position of the “FOCUS” mark may be selected, the innermost position of the “FOCUS” mark may be selected, or all the “FOCUS” marks may be selected.
A mark may be selected. As for the reticle reference plate, the position of the outermost image height may be selected, the position of the innermost image height may be selected, or all image height positions may be selected.

The measurement field of view at the time of TTR measurement is the “pattern position” of the reticle information, the “mark position” of the reticle reference plate and the “pattern position” of the base printing information, or the “mark position” of the stage reference plate.
According to the positional relationship between the observation scope and the stage, if the marks on the reticle side and the wafer stage side can be observed simultaneously by the left and right observation scopes, set the left and right measurement fields of view,
If observation is not possible at the same time, an observation field is set on the right or left side.

<Embodiment 4> The exposure apparatus of the present embodiment
Reticle information as shown in Table 2 used for wafer exposure is stored in advance. In the present embodiment, a description will be given of a measurement condition determination unit that automatically determines measurement conditions at the time of autofocus measurement from reticle information and wafer exposure conditions. The measurement mark is selected based on the "pattern shape" and "pattern line width" included in the reticle information, or the "mark shape" and "mark line width" of the reticle reference plate and the "exposure shot size" included in the wafer exposure conditions. Sort out.

In this case, whether the “FOCUS” mark on the reticle or the “FOCUS” mark on the reticle reference plate corresponding to the inside of the shot specified by the “exposure shot size” of the wafer exposure condition is selected. Either the “FOCUS” mark on the reticle or the “FOCUS” mark on the reticle reference plate corresponding to the outside of the shot specified by the “exposure shot size” may be selected.

Further, a “FOCUS” mark having the same line width as the “pattern line width” of the actual element pattern of the reticle information or the closest line width inside the shot designated by the “exposure shot size” is selected. It is desirable to do.

Next, the measurement position is the “pattern position” of the “FOCUS” mark determined by selecting the measurement mark.

The measurement field of view at the time of TTR measurement is the “pattern position” of the reticle information, the “mark position” of the reticle reference plate and the “pattern position” of the base printing information, or the “mark position” of the stage reference plate.
Depending on the positional relationship between the observation scope and the stage, the left and right observation scopes can set the left and right measurement fields if the marks on the reticle and stage sides can be observed at the same time. Set.

<Embodiment of Semiconductor Production System> Each information of "reticle information", "underlay printing information", and "wafer exposure condition" of the present invention can be stored in a host computer, another exposure apparatus, and an exposure apparatus via a network line or the like. It is possible to transmit and receive data to and from other semiconductor manufacturing apparatuses.

Next, semiconductor devices (semiconductor chips such as ICs and LSIs, liquid crystal panels, CCDs, thin-film magnetic heads,
An example of a production system such as a micromachine will be described. In this system, maintenance services such as troubleshooting and periodic maintenance of a manufacturing apparatus installed in a semiconductor manufacturing factory or provision of software are performed using a computer network outside the manufacturing factory.

FIG. 6 shows the whole system cut out from a certain angle. In the figure, reference numeral 101 denotes a business establishment of a vendor (apparatus supply maker) that provides a semiconductor device manufacturing apparatus. As an example of a manufacturing apparatus, a semiconductor manufacturing apparatus for various processes used in a semiconductor manufacturing plant, for example,
Pre-process equipment (lithography equipment such as exposure equipment, resist processing equipment, etching equipment, heat treatment equipment, film formation equipment,
It is assumed that flattening equipment and the like and post-processing equipment (assembly equipment, inspection equipment, etc.) are used. In the business office 101, a host management system 10 for providing a maintenance database of manufacturing equipment
8. It has a plurality of operation terminal computers 110 and a local area network (LAN) 109 connecting these to construct an intranet. Host management system 10
8 is a gateway for connecting the LAN 109 to the Internet 105 which is an external network of the business office;
Equipped with a security function to restrict external access.

On the other hand, reference numerals 102 to 104 denote manufacturing factories of a semiconductor manufacturer as users of the manufacturing apparatus. The manufacturing factories 102 to 104 may be factories belonging to different manufacturers or factories belonging to the same manufacturer (for example, a factory for a pre-process, a factory for a post-process, etc.). In each of the factories 102 to 104, a plurality of manufacturing apparatuses 106, a local area network (LAN) 111 connecting them to construct an intranet, and a host management unit as a monitoring apparatus for monitoring the operation status of each manufacturing apparatus 106. A system 107 is provided. Each factory 10
The host management systems 107 provided in 2 to 104 are:
A gateway is provided for connecting the LAN 111 in each factory to the Internet 105 which is an external network of the factory. As a result, access to the host management system 108 on the vendor 101 side from the LAN 111 of each factory via the Internet 105 is possible, and access is limited to only users limited by the security function of the host management system 108. More specifically, the factory notifies the vendor of status information indicating the operating status of each manufacturing apparatus 106 (for example, the symptom of the manufacturing apparatus in which a trouble has occurred) via the Internet 105, and responds to the notification. Response information (for example, information instructing a coping method for a trouble, software and data for coping), and maintenance information such as the latest software and help information can be received from the vendor. Each factory 10
The data communication between the vendors 2 to 104 and the vendor 101 and the data communication on the LAN 111 in each factory are performed using a communication protocol (TCP) generally used on the Internet.
/ IP) is used. Instead of using the Internet as an external network outside the factory, it is also possible to use a dedicated line network (such as ISDN) that cannot be accessed by a third party and has high security. Further, the host management system is not limited to the one provided by the vendor, and a user may construct a database and place the database on an external network, and permit a plurality of factories of the user to access the database.

FIG. 7 is a conceptual diagram showing the entire system according to the present embodiment cut out from an angle different from that of FIG. In the above example, a plurality of user factories each having a manufacturing device and a management system of a vendor of the manufacturing device are connected via an external network, and the production management of each factory and at least one device are connected via the external network. The data of the manufacturing apparatus was communicated. On the other hand, in this example, a factory equipped with manufacturing equipment of a plurality of vendors and a management system of each vendor of the plurality of manufacturing apparatuses are connected via an external network outside the factory, and maintenance information of each manufacturing equipment is stored. It is for data communication. In the figure, reference numeral 201 denotes a manufacturing factory of a manufacturing apparatus user (semiconductor device manufacturer);
A manufacturing apparatus for performing various processes, for example, an exposure apparatus 202 and a resist processing apparatus 20 are provided on a manufacturing line of a factory.
Third, a film forming apparatus 204 is introduced. Although only one manufacturing factory 201 is illustrated in FIG. 7, a plurality of factories are actually networked similarly. Each device in the factory is connected by a LAN 206 to form an intranet, and the host management system 205 manages the operation of the production line. On the other hand, each business establishment of a vendor (apparatus maker) such as an exposure apparatus maker 210, a resist processing apparatus maker 220, and a film forming apparatus maker 230 has a host management system 211, 221 for performing remote maintenance of the supplied apparatus. 231 which comprise a maintenance database and an external network gateway as described above. The host management system 205 that manages each device in the user's manufacturing factory and the management systems 211, 221, and 231 of the vendors of each device are connected to the external network 2
00 is connected by the Internet or a dedicated line network. In this system, if a trouble occurs in any of a series of manufacturing equipment on the manufacturing line, the operation of the manufacturing line is stopped, but remote maintenance is performed via the Internet 200 from a vendor of the troubled equipment. As a result, quick response is possible, and downtime of the production line can be minimized.

Each manufacturing apparatus installed in the semiconductor manufacturing factory has a display, a network interface, and a computer for executing network access software and apparatus operation software stored in a storage device. The storage device is a built-in memory, a hard disk, a network file server, or the like. The network access software includes a dedicated or general-purpose web browser, and provides, for example, a user interface having a screen as shown in FIG. 8 on a display. The operator who manages the manufacturing equipment at each factory refers to the screen and refers to the manufacturing equipment model (401), serial number (402), trouble subject (403), date of occurrence (404), and urgency (40).
5), symptom (406), coping method (407), course (40)
8) Input information such as in the input items on the screen. The input information is transmitted to the maintenance database via the Internet, and the resulting appropriate maintenance information is returned from the maintenance database and presented on the display. Further, the user interface provided by the web browser further realizes a hyperlink function (410 to 412) as shown in the figure, so that the operator can access more detailed information of each item or use the software library provided by the vendor for the manufacturing apparatus. The latest version of software to be extracted can be extracted, and an operation guide (help information) can be extracted for reference by a factory operator. Here, the maintenance information provided by the maintenance database includes the underprinting information, the reticle information,
The software library also provides the latest software for automatically determining measurement conditions, including wafer exposure conditions and the like.

Next, a manufacturing process of a semiconductor device using the above-described production system will be described. FIG. 9 shows a flow of the whole semiconductor device manufacturing process. In step 1 (circuit design), the circuit of the semiconductor device is designed. Step 2 is a process for making a mask on the basis of the circuit pattern design. Step 3
In (wafer manufacture), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and assembly such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). Process. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7). The pre-process and the post-process are performed in separate dedicated factories, and maintenance is performed for each of these factories by the above-described remote maintenance system. Also, information for production management and equipment maintenance is communicated between the pre-process factory and the post-process factory via the Internet or a dedicated line network.

FIG. 10 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. Step 1
In 5 (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus to print and expose the circuit pattern of the mask onto the wafer. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer. Since the manufacturing equipment used in each process is maintained by the remote maintenance system described above, troubles can be prevented beforehand, and if troubles occur, quick recovery is possible. Productivity can be improved.

[0079]

As described above, according to the present invention, it is possible to automatically select and determine the setting of the measurement conditions at the time of alignment measurement and autofocus measurement. There is no need to set the used parameters, and the burden on the operator can be reduced.

In addition, it is possible to prevent parameter input errors and to perform alignment measurement and auto force measurement under optimal conditions, so that improvement in measurement accuracy can be expected.

[Brief description of the drawings]

FIG. 1 is an image diagram showing “difference from reference offset” and “displacement amount” included in an alignment measurement value of background printing information.

FIG. 2 is a wafer image diagram based on underlay printing information.

FIG. 3 is a wafer image diagram of underlay printing information and exposure shot arrangement.

FIG. 4 is a wafer image diagram of underlay printing information and exposure shot arrangement.

FIG. 5 is a wafer image diagram of underlay printing information and an exposure shot arrangement.

FIG. 6 is a conceptual diagram of a semiconductor device production system viewed from a certain angle.

FIG. 7 is a conceptual diagram of a semiconductor device production system viewed from another angle.

FIG. 8 is a specific example of a user interface.

FIG. 9 is a diagram illustrating a flow of a device manufacturing process.

FIG. 10 is a diagram illustrating a wafer process.

[Explanation of symbols]

1,3: pre-alignment specified shot, 2, 4: global alignment specified shot.

Claims (43)

[Claims] 1. An exposure apparatus for projecting and exposing a pattern on an original plate onto a photosensitive substrate mounted on a movable stage via a projection optical system, wherein the reticle information on the pattern on the original plate and the reticle information on the photosensitive substrate An exposure apparatus, comprising: a measurement condition determining unit that determines a measurement condition when performing the projection exposure with reference to at least one piece of information selected from background printing information regarding a pattern to be printed. 2. A method according to claim 1, wherein said measuring condition determining means selects from underprinting information, reticle information and wafer exposure conditions preset for said exposure processing when providing a plurality of layers by repeatedly exposing said photosensitive substrate. 2. The exposure apparatus according to claim 1, wherein a measurement condition for performing alignment measurement of the photosensitive substrate is determined based on at least one piece of information obtained. 3. The measurement condition determination means according to claim 2, wherein said measurement condition determination means is configured to perform a measurement condition of an autofocus measurement based on at least one information selected from underprinting information, reticle information and wafer exposure condition when performing projection exposure on said photosensitive substrate. The exposure apparatus according to claim 1, wherein the exposure apparatus determines: 4. The underlay printing information is stored in a table format for each layer, and includes the shape, position, size, printing direction and line width of each pattern printed as the underlayer, and information on the under exposure. The exposure apparatus according to any one of claims 1 to 3, further comprising at least one information selected from an alignment measurement value, an exposure apparatus type, and an exposure size. 5. The information according to claim 1, wherein the underprinting information can be updated by an exposure apparatus that has performed exposure or alignment measurement.
Exposure apparatus according to Item. 6. The exposure apparatus according to claim 4, wherein the alignment measurement value includes a measured shift amount and a difference between a reference offset and an apparatus-specific offset. 7. The reticle information includes at least one information selected from a shape, a position, a size and a line width of a pattern at the time of designing a master, and an identifier and a focus position for specifying the master. Claim 1.
The exposure apparatus according to any one of claims 1 to 6. 8. The apparatus according to claim 1, wherein the underprinting information and / or the reticle information can be transmitted / received to / from another exposure apparatus connected to a network line. Exposure apparatus according to Item. 9. The apparatus according to claim 1, wherein the underprinting information and / or the reticle information can be transmitted / received to / from a computer device connected to a network line. Exposure apparatus according to the above. 10. The exposure according to claim 1, wherein the underprinting information and / or the reticle information can be stored in a portable storage medium. apparatus. 11. The method according to claim 1, wherein said measurement condition determination means determines a measurement mark used at the time of alignment measurement from a plurality of measurement marks provided on said photosensitive substrate. Exposure apparatus according to Item. 12. The exposure apparatus according to claim 1, wherein the measurement condition determination means determines a mark measurement position on the photosensitive substrate at the time of alignment measurement. 13. The exposure apparatus according to claim 1, wherein the measurement condition determination unit determines measurement execution timing at the time of autofocus measurement based on a wafer exposure condition. 14. The method according to claim 1, wherein said measurement condition determining means determines a measurement mark at the time of autofocus measurement from a plurality of measurement marks provided on said original plate or on a reference plate. Exposure apparatus according to Item. 15. The exposure apparatus according to claim 1, wherein the measurement condition determination unit determines a measurement visual field at the time of autofocus measurement. 16. The exposure apparatus according to claim 1, wherein said measurement condition determination means determines a measurement position at the time of autofocus measurement. 17. The method according to claim 17, wherein the measurement condition determination unit determines a method of correcting a measurement value at the time of autofocus measurement by using a wafer exposure condition,
2. The method according to claim 1, wherein the determination is made based on a measurement position.
The exposure apparatus according to any one of claims 16 to 16. 18. An exposure method for projecting and exposing a pattern on an original plate onto a photosensitive substrate mounted on a movable stage via a projection optical system, the reticle information relating to the pattern on the original plate and the reticle information already on the photosensitive substrate. An exposure method, comprising: a measurement condition determining step of determining a measurement condition when performing the projection exposure by referring to at least one piece of information selected from underlay printing information on a printed pattern. 19. The method according to claim 19, wherein the step of determining the measurement conditions comprises the steps of:
19. The measurement condition for performing alignment measurement of the photosensitive substrate based on at least one information selected from underlay printing information, reticle information, and wafer exposure conditions. Exposure method. 20. The step of deciding the measurement and measurement condition, wherein the projection and exposure are performed on the photosensitive substrate based on at least one information selected from underprinting information, reticle information and wafer exposure condition. 20. The exposure method according to claim 18, wherein conditions are determined. 21. The base printing information is stored in a table format for each layer, and the shape, position, size, printing direction and line width of each pattern printed as a base, and the base exposure information at the time of base exposure. 21. At least one information selected from an alignment measurement value, an exposure apparatus type, and an exposure size is included.
The exposure method according to any one of the above. 22. The exposure method according to claim 18, wherein the underprinting information can be updated by an exposure apparatus that has performed exposure or alignment measurement. 23. The exposure method according to claim 21, wherein the alignment measurement value includes a measured shift amount and a difference between a reference offset and an apparatus-specific offset. 24. The reticle information includes at least one information selected from a shape, a position, a size and a line width of a pattern at the time of designing a master, and an identifier and a focus position for specifying the master. The exposure method according to any one of claims 18 to 23, wherein: 25. The apparatus according to claim 18, wherein the underprinting information and / or the reticle information are received from another exposure apparatus connected to a network line.
25. The exposure method according to any one of 24. 26. The apparatus according to claim 1, wherein the underprinting information and / or the reticle information are received from a computer device connected to a network line.
The exposure method according to any one of items 8 to 25. 27. The apparatus according to claim 18, wherein the underprinting information and / or the reticle information are read from a portable storage medium.
Exposure method according to item. 28. The method according to claim 18, wherein the measurement condition determination step is to determine a measurement mark used for alignment measurement from a plurality of measurement marks provided on the photosensitive substrate. Exposure method according to 1. 29. The exposure method according to claim 18, wherein the measurement condition determining step determines a mark measurement position on the photosensitive substrate at the time of alignment measurement. 30. The exposure method according to claim 18, wherein in the measurement condition determination step, measurement execution timing at the time of autofocus measurement is determined based on a wafer exposure condition. 31. The exposure method according to claim 18, wherein the measurement condition determining step determines a measurement mark at the time of autofocus measurement. 32. The exposure method according to claim 18, wherein the measurement condition determination step determines a measurement visual field at the time of autofocus measurement. 33. The measurement condition determination step, wherein the measurement position at the time of autofocus measurement is at least one selected from underprint printing information, reticle information, and wafer exposure conditions.
The information is determined based on two pieces of information.
33. The exposure method according to any one of items 32. 34. The method according to claim 18, wherein in the measurement condition determining step, a method of correcting a measurement value at the time of autofocus measurement is determined based on a wafer exposure condition and a measurement position.
35. The exposure method according to any one of items 33 to 33. 35. An alignment measurement of a projection exposure apparatus configured to detect a measurement reference point formed on a photosensitive substrate, perform exposure based on the measurement reference point, and form a semiconductor chip in each region on the photosensitive substrate. A program for determining a mark measurement position at the time of alignment measurement based on at least one information selected from underlay printing information, reticle information, and wafer exposure conditions. And a second step of determining a measurement mark at the time of alignment measurement based on at least one information selected from base printing information, reticle information, and wafer exposure conditions. 36. Detecting an optimum focus position on a photosensitive substrate surface,
A recording medium recording a program for executing autofocus measurement of a projection exposure apparatus that performs exposure based on the optimum focus position, the program determining a measurement execution timing at the time of autofocus measurement based on a wafer exposure condition. A second step of determining a mark measurement position at the time of autofocus measurement based on at least one of information of underprinting information, reticle information, and wafer exposure conditions; a measurement visual field at the time of autofocus measurement; underprinting information; reticle information; , At least one of the wafer exposure conditions
A third step of determining the measurement mark at the time of autofocus measurement, at least one of base printing information, reticle information, and wafer exposure conditions;
A recording medium comprising: a fourth step of determining from at least one piece of information; and a fifth step of determining a method of correcting a measurement value during autofocus measurement based on a measurement position and wafer exposure conditions. 37. A step of installing a group of manufacturing apparatuses for various processes including the exposure apparatus according to claim 1 in a semiconductor manufacturing factory, and a step of manufacturing a semiconductor device by a plurality of processes using the group of manufacturing apparatuses. A device manufacturing method comprising: 38. A step of connecting the group of manufacturing apparatuses via a local area network, and data communication between at least one of the group of manufacturing apparatuses between the local area network and an external network outside the semiconductor manufacturing plant. 38. The method of claim 37, further comprising the step of: 39. A semiconductor manufacturing factory different from the semiconductor manufacturing factory by accessing a database provided by a vendor or a user of the exposure apparatus via the external network to obtain maintenance information of the manufacturing apparatus by data communication. 38. The method according to claim 37, wherein the production management is performed by data communication with the external network via the external network. 40. A group of manufacturing apparatuses for various processes including the exposure apparatus according to claim 1, a local area network connecting the group of manufacturing apparatuses, and an external network outside the factory can be accessed from the local area network. A semiconductor manufacturing plant having a gateway for performing data communication of information on at least one of the manufacturing apparatus groups. 41. The semiconductor device according to claim 1, which is installed in a semiconductor manufacturing plant.
18. The maintenance method for an exposure apparatus according to any one of claims 17 to 17, wherein a vendor or a user of the exposure apparatus provides a maintenance database connected to an external network of the semiconductor manufacturing plant; and A step of permitting access to the maintenance database via the external device, and a step of transmitting maintenance information stored in the maintenance database to the semiconductor manufacturing plant via the external network. Method. 42. The exposure apparatus according to claim 1, wherein a display, a network interface,
An exposure apparatus, further comprising: a computer that executes network software, and capable of performing data communication of maintenance information of the exposure apparatus via a computer network. 43. The network software,
Provided on the display is a user interface for accessing a maintenance database provided by a vendor or a user of the exposure apparatus connected to an external network of a factory where the exposure apparatus is installed, and from the database via the external network. 43. The device according to claim 42, which makes it possible to obtain information.