JP2006203123A - Display method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it more efficient for an operator to evaluate measurement results of wafer alignment and superposition errors. <P>SOLUTION: On the Alignment Map Window displayed on the exposure system screen, the EGA processing result file and the superposition error measurement result file are selected in the file selection field, then specific display requirements are set up including EGA statistical model (EGA Calc Model), "Correction Components", "Display Mode", and correction parameters (No. 1, No. 2) in the display requirement settings fields for each display file. This operation allows for simultaneous display of vector maps of at least two kinds of data selected among many kinds of data concerning wafer alignment and superposition error measurement results in accordance with the display requirement settings on the wafer shot-map image display area. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display method and a program, and more specifically, a new partitioned area is overlaid on each partitioned area in a state where each of the partitioned areas arranged on at least one object is aligned with a predetermined point. The present invention relates to a display method for displaying information related to at least one of alignment and superposition obtained when forming together and a program for causing a computer to execute a display procedure for realizing the display method.

  In recent years, in a manufacturing process of a device such as a semiconductor element, an exposure apparatus such as a step-and-repeat system or a step-and-scan system, a wafer prober, or a laser repair apparatus is used. In these apparatuses, each of a plurality of shot areas arranged on the substrate is set to a stationary coordinate system that defines the moving position of the substrate (that is, an orthogonal coordinate system defined by a laser interferometer, which is a stage coordinate system). It is necessary to align (align) very precisely with a predetermined reference point (for example, a processing point of various apparatuses).

  In particular, in an exposure apparatus, a circuit pattern (reticle pattern) of 10 layers or more is superimposed and transferred onto a substrate (hereinafter referred to as “wafer”). The above characteristics can be inconvenient. In such a case, the chip does not satisfy the desired characteristics, and in the worst case, the chip becomes a defective product, which reduces the yield. Therefore, in the exposure apparatus, an alignment mark is previously attached to each of a plurality of shot areas on the wafer, and the position (coordinate value) of the mark in the stage coordinate system is detected. Thereafter, wafer alignment is performed for aligning one shot area on the wafer with the reticle pattern based on the mark position information and the position information of a known reticle pattern (which is measured in advance).

  As one of the wafer alignments, there is a global alignment method in which each shot area is aligned by detecting wafer marks in several shot areas on the wafer to obtain regularity of the shot area arrangement. Among them, an enhanced global alignment (EGA) method that accurately specifies the regularity of the arrangement of shot areas on a wafer by a statistical method has become the mainstream (see, for example, Patent Document 1 and Patent Document 2).

  In the EGA method, first, position coordinates on a stage coordinate system of a plurality of shot areas (hereinafter also referred to as “sample shot areas”) on a wafer are actually measured. The design positions of a plurality (three or more, usually about 7 to 15) of sample shot areas on the arrangement coordinate system defined by the actual measurement values and the shot area arrangement on the wafer. At the time of the conversion, statistical analysis processing (for example, least square method) is used so that the fitting error with the position coordinates obtained when the coordinates are converted to the position coordinates on the stage coordinate system is as small as possible. Error parameter values such as scaling, rotation, and offset used in the above are obtained. Further, the position coordinates of each shot region in the stage coordinate system are calculated based on the regression model defined by the obtained error parameter values.

  By the way, since the EGA processing result is directly linked to the overlay accuracy between the layers, it is desirable that the EGA process result can be evaluated later in order to improve the overlay accuracy. Therefore, conventionally, in the exposure apparatus, the EGA processing results, for example, the measured position coordinates of the sample shot area, the correction amount of the position coordinates based on the regression model, the corrected position coordinates of the sample shot area and the measured position coordinates, The difference (residual) data is stored in a file format, and when the operator wants to evaluate the EGA processing result, the contents of the file (EGA processing result file) are read and displayed on the display. The operator can confirm the processing result of EGA.

  In the display of the EGA processing result, a shot map of the wafer is displayed as an image on the display, and the measured position coordinates of the sample shot area, the correction amount of the position coordinates based on the regression model, In general, any one kind of data among the various data such as a difference (residual) between the position coordinates of the sample shot area and the actually measured position coordinates is displayed as a vector. By doing so, the operator can visually grasp the processing content of the EGA processing result and can easily grasp it. However, in this display format, the measured position coordinates of the sample shot area, the correction amount of the position coordinates based on the regression model, the difference (residual) between the corrected position coordinates of the sample shot area and the measured position coordinates, etc. Among various data, only one type of data can be displayed at the same time, and it is difficult to evaluate the correlation between the various data.

JP-A 61-44429 JP-A-62-84516

  According to the first aspect of the present invention, a plurality of partitioned areas arranged on at least one object are aligned with predetermined points, and a new partitioned area is formed on each partitioned area. A display method for displaying information on at least one of alignment and overlay obtained at the time, and simultaneously displaying at least two types of information of a plurality of types of information on at least one of the alignment and overlay A display method including a display step.

  Here, “information relating to alignment” includes all information relating to alignment such as information used for alignment, information calculated in the process, and processing results. Further, the “information related to overlay” includes all information related to overlay such as overlay error measurement results and analysis results of the measurement results.

  According to this, alignment and overlap obtained when aligning each of a plurality of partitioned areas arranged on at least one object to a predetermined point and forming a new partitioned area superimposed on the partitioned area. Since at least two types of information of a plurality of types of information related to at least one of the combinations are displayed at the same time, a person who sees the display can easily grasp the correlation between the information.

  According to a second aspect of the present invention, a plurality of partitioned areas arranged on at least one object are aligned with a predetermined point and a new partitioned area is formed on each partitioned area. A program for causing a computer to execute processing for displaying information related to at least one of alignment and superposition obtained at the time, wherein at least two types of information regarding at least one of the alignment and superposition A program for causing a computer to execute a display procedure for simultaneously displaying information.

  According to this, alignment and overlap obtained when aligning each of a plurality of partitioned areas arranged on at least one object to a predetermined point and forming a new partitioned area superimposed on the partitioned area. Since it is possible to cause the computer to execute a processing procedure for simultaneously displaying at least two types of information of at least one of the combinations, it is possible for the operator to easily grasp the correlation between them.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 shows a schematic configuration of an exposure apparatus 100 according to an embodiment to which the display method of the present invention is applied. As shown in FIG. 1, an exposure apparatus 100 includes an illumination system 10 that illuminates a reticle R as a mask with illumination light (exposure light) IL as an energy beam, a reticle stage RST that holds the reticle R, and a projection optical system PL. , A wafer stage WST on which a wafer W as an object is mounted, a main controller 20 that performs overall control of the entire apparatus, and the like. The exposure apparatus 100 is a step-and-scan projection exposure apparatus (so-called scanning stepper (also called a scanner)).

  The illumination system 10 includes a light source, an illuminance uniformizing optical system including an optical integrator, a relay lens, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-313250 (corresponding US Patent Application Publication No. 2003/0025890). A variable ND filter, a reticle blind (also called a masking blade), a dichroic mirror, and the like (all not shown) are included. In this illumination system 10, a slit-shaped illumination area defined by a reticle blind on a reticle R on which a circuit pattern or the like is drawn is illuminated with illumination light IL with a substantially uniform illuminance.

Here, as the illumination light IL, far ultraviolet light such as KrF excimer laser light (wavelength 248 nm), vacuum ultraviolet light such as ArF excimer laser light (wavelength 193 nm), F ₂ laser light (wavelength 157 nm), or the like is used. . As the illumination light IL, it is also possible to use an ultraviolet bright line (g-line, i-line, etc.) from an ultra-high pressure mercury lamp. As the optical integrator, a fly-eye lens, a rod integrator (an internal reflection type integrator), a diffractive optical element, or the like is used.

  On reticle stage RST, reticle R is fixed, for example, by vacuum suction. Reticle stage RST can be finely driven in an XY plane perpendicular to the optical axis of illumination system 10 (corresponding to optical axis AX of projection optical system PL described later) by a reticle stage drive unit (not shown) including a linear motor, for example. In addition, it can be driven at a scanning speed designated in a predetermined scanning direction (here, the Y-axis direction which is the horizontal direction in FIG. 1).

  The position of the reticle stage RST in the stage moving surface is always detected by a reticle laser interferometer (hereinafter referred to as “reticle interferometer”) 16 via a movable mirror 15 with a resolution of about 0.5 to 1 nm, for example. Yes. Position information of reticle stage RST from reticle interferometer 16 is supplied to stage controller 19 and main controller 20 via this. In response to an instruction from main controller 20, stage controller 19 controls driving of reticle stage RST via a reticle stage drive unit (not shown) based on position information of reticle stage RST. A pair of reticle alignment systems (not shown) is disposed above the reticle R. Since the configuration of the pair of reticle alignment systems is disclosed in, for example, Japanese Patent Laid-Open No. 7-176468, detailed description thereof is omitted here.

  The projection optical system PL is disposed below the reticle stage RST in FIG. 1, and the direction of the optical axis AX is the Z-axis direction. As projection optical system PL, for example, a double telecentric reduction system is used. The projection magnification of the projection optical system PL is, for example, 1/4, 1/5, or 1/6. For this reason, when the reticle R is illuminated by the illumination light IL from the illumination system 10, the illumination light irradiation region (the above-described illumination region) is irradiated by the illumination light IL that has passed through the reticle R via the projection optical system PL. A reduced image (partial image) of the circuit pattern of the inner reticle R is formed on the wafer W whose surface is coated with a resist (photosensitive agent).

  Wafer stage WST is arranged on a base (not shown) below projection optical system PL in FIG. 1, and is, for example, a wafer stage driving unit 24 including a linear motor and the like in the Y-axis direction and the X-axis direction ( It is configured to be driven with a predetermined stroke in the direction orthogonal to the paper surface in FIG. Wafer holder 25 is placed on wafer stage WST, and wafer W is fixed on wafer holder 25 by, for example, vacuum suction.

  The position of wafer stage WST in the XY plane is always detected by a wafer laser interferometer system 18 through a moving mirror 17 provided on the upper surface thereof with a resolution of, for example, about 0.5 to 1 nm. Here, actually, on wafer stage WST, a Y moving mirror having a reflecting surface orthogonal to the scanning direction (Y direction) and an X moving mirror having a reflecting surface orthogonal to the non-scanning direction (X axis direction) Correspondingly, the wafer laser interferometer is also provided with a Y interferometer that irradiates the interferometer beam perpendicularly to the Y movable mirror and an X interferometer that irradiates the interferometer beam perpendicularly to the X movable mirror. In FIG. 1, these are typically shown as a movable mirror 17 and a wafer laser interferometer system 18. That is, in this embodiment, a stationary coordinate system (orthogonal coordinate system) that defines the movement position of wafer stage WST is defined by the measurement axes of the Y interferometer and X interferometer of wafer laser interferometer system 18. Hereinafter, this stationary coordinate system is also referred to as a “stage coordinate system”. The end surface of wafer stage WST may be mirror-finished to form the above-described interferometer beam reflecting surface (corresponding to the reflecting surface of the Y moving mirror and X moving mirror).

  Position information (or speed information) of wafer stage WST on the stage coordinate system is supplied to stage controller 19 and main controller 20 via this. In accordance with an instruction from main controller 20, stage controller 19 controls wafer stage WST via wafer stage drive unit 24 based on the position information (or speed information) of wafer stage WST.

  A reference mark plate FM is fixed in the vicinity of wafer W on wafer stage WST. The surface of the reference mark plate FM is set to the same height as the surface of the wafer W, and a reference mark for baseline measurement of the alignment system, a reference mark for reticle alignment, and other reference marks to be described later are formed on this surface. Has been.

  The alignment detection system AS is an off-axis alignment sensor disposed on the side surface of the projection optical system PL. As this alignment detection system AS, for example, a broadband detection light beam that does not sensitize a resist on a wafer is irradiated onto a target mark, and an image of the target mark formed on a light receiving surface by reflected light from the target mark is not shown. An image processing type FIA (Field Image Alignment) type sensor that captures an image of an index using an imaging device (CCD) or the like and outputs an image pickup signal thereof is used. In addition to the FIA system, a target mark is irradiated with coherent detection light, and scattered light or diffracted light generated from the target mark is detected, or two diffracted lights (for example, of the same order) generated from the target mark. Of course, it is possible to use an alignment sensor for detecting the interference by using them alone or in combination as appropriate. The imaging result of the alignment detection system AS is output to the main controller 20 via an alignment signal processing system (not shown).

  The exposure apparatus 100 further supplies an imaging light beam for forming a plurality of slit images toward the best imaging plane of the projection optical system PL from an oblique direction (not shown) that is oblique to the optical axis AX direction. An oblique incidence type multi-point focus detection system comprising a system and a light receiving optical system (not shown) that receives each reflected light beam of the imaging light beam on the surface of the wafer W through a slit is provided as a projection optical system PL. It is being fixed to the support part (illustration omitted) to support. As this multipoint focus detection system, for example, one having the same configuration as that disclosed in JP-A-6-283403 (corresponding US Pat. No. 5,448,332) is used, and the stage control device 19 is used. Based on the wafer position information from the multipoint focus detection system, the wafer stage WST is finely driven in the Z-axis direction and the tilt direction (θx direction and θy direction) via the wafer stage driving unit 24 to focus the wafer W. -Perform leveling control.

  The stage controller 19 performs the above-described operations (position control operation of the wafer stage WST, reticle stage RST, etc.) under the instruction of the main controller 20.

  The main control device 20 includes a microcomputer or a workstation, and controls each part of the device in an integrated manner. The main controller 20 includes a CPU for executing various programs for controlling the operation of the exposure apparatus, an internal memory for storing the programs and various data, and a storage device such as a hard disk (all not shown). ing. The main controller 20 stores the alignment results and exposure results (superimposition results), which will be described later, in a data file format in association with the lot number, wafer number, shot area number, and the like to which the wafer belongs. . The main controller 20 is connected to a display device 21 as a man-machine interface, a keyboard (not shown), and a mouse (pointing device). The display device 21 displays a screen and the like to be described later by a graphic user interface (hereinafter referred to as “GUI”) provided by an operating system that controls the CPU of the main control device 20. The keyboard is operated by an operator for text input, for example, and the mouse is used to move a cursor displayed on the screen of the display device 21 within the screen, or an object displayed on the screen of the display device 21. Is designated by an operator.

  Next, a series of exposure operations in the exposure apparatus 100 will be described. First, a reticle R on which a circuit pattern to be transferred is formed is loaded onto a reticle stage RST by a reticle loader (not shown). The main controller 20 and the stage controller 19 perform preparation work such as reticle alignment and baseline measurement using a reticle alignment detection system (not shown), a reference mark plate FM on the wafer stage WST, an alignment detection system AS, and the like. After being performed according to a predetermined procedure, a wafer W to be exposed is loaded onto wafer stage WST by a wafer loader (not shown).

On the wafer W, as shown in FIG. 2A, a plurality of (for example, N) shot regions SA _P (p = 1, 2,..., N) are adjacent to each other in the processing steps up to the previous layer. place the 100μm width of about the spacing between shot areas (street lines) that are formed in a matrix-like arrangement, the four corners of each shot area SA _P (on street line), the wafer alignment detection two-dimensional position Marks (wafer marks) _{MP, K} (K = 1, 2, 3, 4) are formed. The axes of the array coordinate system defined by the arrangement of shot areas SA _P alpha axis (an axis substantially parallel to the X axis), and β-axis (an axis substantially parallel to the Y axis), completely and alpha axis and X-axis Assuming that the β axis and the Y axis completely match, the average value of the X positions of the wafer marks M _{P, 1,} M _{P, 2,} M _{P, 3,} M _{P, 4} is The average value of the Y positions of the wafer marks M _{P, 1,} M _{P, 2,} M _{P, 3,} M _{P, 4} coincides with the X coordinate of SA _P (center C _P ) of the shot area SA _P ( It is arranged so as to coincide with the Y coordinate of the center C _P ). That is, in design, the position coordinates of the shot area SA _P (the center C _P ) can be obtained based on the X position and the Y position of each wafer X mark M _{P, K.}

In this case, as the wafer marks _{MP, K} , for example, cross marks formed by lines extending in the X-axis (α-axis) direction and the Y-axis (β-axis) direction intersecting each other are used. These marks may be box marks instead of cross marks, and a line-and-space pattern (L / S pattern) having the α-axis direction as the arrangement direction and the β-axis direction as the arrangement direction. Or a combination of the various marks described above.

  Next, search alignment is performed using the alignment detection system AS. At least two places on the wafer are provided with marks that can be observed at a low magnification by an observation apparatus, so-called search alignment marks (hereinafter abbreviated as “search marks”). Main controller 20 provides stage controller 19 with a target position of wafer stage WST that sequentially positions the search marks within the detection field of alignment detection system AS. The stage controller 19 sequentially positions the wafer stage WST via the wafer stage drive unit 24 in accordance with the target position. At each positioning, main controller 20 detects the position information of each search mark using alignment detection system AS, and rotates the wafer relative to the stage coordinate system based on the detection result (detection position of each search mark). The component and the offset component are calculated. In the future, the coordinate system detected based on this search alignment will be the reference coordinate system for positioning wafer stage WST. Hereinafter, this is referred to as a “reference coordinate system”.

  Next, main controller 20 is attached to each of a plurality of shot regions (sample shots) already formed on wafer W in the original process in consideration of the reference coordinate system defined by the search alignment result. A target position of wafer stage WST is provided to stage controller 19 so that fine alignment marks (hereinafter abbreviated as “wafer marks”) are sequentially positioned within the detection field of alignment detection system AS. The stage controller 19 sequentially positions the wafer stage WST via the wafer stage drive unit 24 in accordance with the target position. Each time the positioning is performed, main controller 20 causes alignment detection system AS to detect the wafer mark at a high magnification, and calculates the position information of the wafer mark based on the detection result.

  The main controller 20 performs EGA wafer alignment based on the calculated wafer mark position information. Here, first, EGA wafer alignment will be described. What is obtained by this wafer alignment is a deviation between the reference coordinate system (X, Y) and the wafer coordinate system (α, β) defined by the shot arrangement. The deviation between the two coordinate systems can be mainly divided into a rotation component, a scaling component, and an offset component. Considering these components, the deviation (ΔX1, ΔY1) between the reference coordinate system and the wafer coordinate system in the X axis direction and the Y axis direction can be defined by the following equations.

Here, (Wx, Wy) is the design position of the wafer mark in the wafer coordinate system with the wafer center as the origin. The coefficients Cx_10 and Cy_01 are the wafer scaling X and Y components (Scaling X, Y), the coefficients Cx_01 and Cy_10 are the wafer rotation X and Y components, and Cx_00 and Cy_00 are the offset components ( Offset X, Y).

  Further, when the deviation between the reference coordinate system and the wafer coordinate system is expressed as shown in the above formula (1), the α axis and β axis orthogonality of the wafer coordinate system, that is, the wafer orthogonality (Orthogo) is − It is defined as (Cx — 01 + Cy — 10), and the rotation component (Rotation) of the wafer coordinate system with respect to the reference coordinate system can be defined as Cy — 10.

  The above formula (1) is defined considering only the first order component of the deviation between the reference coordinate system and the wafer coordinate system. However, if the secondary component of the deviation between the reference coordinate system and the wafer coordinate system cannot be ignored, the deviation of the reference coordinate system and the wafer coordinate system in the X-axis direction and the Y-axis direction can be expressed as the above formula ( Instead of 1) the following equation can be defined:

Here, Cx_20 and Cy_20 are coefficients of a quadratic term of Wx, Cx_11 and Cy_11 are coefficients of a term of Wx · Wy, and Cx_02 and Cy_02 are coefficients of a quadratic term of Wy. That is, the correction amount of the position information of the SA _P shot areas represented by the formula (2) (ΔX2, ΔY2) is represented by the formula (1) (ΔX1, ΔY1), the reference coordinate system and the wafer coordinate system The second-order components of the deviation are added to each other.

  Further, when the third-order component of the deviation between the reference coordinate system and the wafer coordinate system cannot be ignored, the deviation between the reference coordinate system and the wafer coordinate system is expressed by the above equations (1) and (2). Instead, we can define

Here, Cx_30 and Cy_30 are the coefficients of the third-order term of Wx, Cx_21 and Cy_21 are the coefficients of the term of Wx ² and Wy, Cx_12 and Cy_12 are the coefficients of the term of Wx and Wy ² , and Cx_03 , Cy_03 are coefficients of the third-order term of Wy. That is, (ΔX3, ΔY3) in the above equation (3) is obtained by adding the third order component of the deviation between the reference coordinate system and the wafer coordinate system to (ΔX2, ΔY2) obtained by the above equation (2). Is.

Further, in the present embodiment, due to the distortion of the shot area SA _P itself, the position of the design between the wafer mark _{M P, 1, M P,} 2, M P, 3, M P, 4 positions and shot center It is also possible to set a model that takes into account the deviation from the relationship, that is, the shot region rotation component (shot rotation component) and the shot region scaling component (shot scaling component). In this case, a statistical model of deviation between coordinate systems can be defined by the following equation.

Here, the coefficients Cx_sx and Cy_sy are shot scaling components, and the coefficients Cx_sy and Cy_sx are shot rotation components. That is, (ΔX4, ΔY4) of the above equation (4) is obtained by adding a component (shot component) of deviation between the wafer coordinate system and the in-shot coordinate system to (ΔX1, ΔY1) obtained by the above equation (1). It is an addition.

  Further, the orthogonality between the two coordinate axes in the in-shot coordinate system, that is, the shot orthogonality can be defined as − (Cx_sy + Cy_sx), and the rotation component of the in-shot coordinate system with respect to the wafer coordinate system can be defined as Cy_sx. it can.

  The above equation (4) is set considering only the first order component of the deviation between the wafer coordinate system and the in-shot coordinate system. However, when the secondary component of the deviation between the reference coordinate system and the wafer coordinate system cannot be ignored, the following equation is defined instead of the above equation (4) as a statistical model of the deviation of each coordinate system. be able to.

That is, the following equation (ΔX5, ΔY5) is obtained by adding a second-order component of deviation between the reference coordinate system and the wafer coordinate system to (ΔX4, ΔY4) represented by the above equation (4).

  Furthermore, when the third-order component of the deviation between the reference coordinate system and the wafer coordinate system cannot be ignored, the following equation should be defined as a statistical model instead of the above equations (4) and (5). Can do.

That is, (ΔX6, ΔY6) in the following equation is obtained by adding a third-order component of deviation between the reference coordinate system and the wafer coordinate system to (ΔX5, ΔY5) expressed in the above equation (5).

In main controller 20, one of the above formulas (1) to (6) is selected as a model formula for defining the deviation between coordinate systems and calculated as a model formula for the arrangement of shot areas. Statistical calculation using the least square method is executed using the position coordinates of the wafer mark, and the coefficient of each term on the right side of the selected model formula is obtained. That is, selected in the model formula, the position coordinates on the design of the wafer mark in the reference coordinate system, the position coordinates of shot areas SA _P is corrected when substituting the position coordinates of the center of the design of the shot area SA _P ( a calculation result of the selected model equation), the wafer mark is actually measured _{M P, 1, M P,} 2, M P, 3, the position coordinates of M _{P, 4} shot area SA _P based on the position coordinates and The coefficient of the equation is obtained so that the residual of is minimized. Then, the coefficient is determined model formula by inputting the position coordinates of the designed shot areas SA _P (or the shot area SA position coordinates on the design of the wafer marks arranged in _P), the shot area SA _P The correction amount of the position coordinate when performing overlay exposure on is obtained.

  Note that the coefficient of each term on the right side in the above formulas (1) to (6) is also called a “correction parameter”, and in the present embodiment, this correction parameter is obtained by a statistical method. This model formula is also called an “EGA statistical model”.

  FIG. 2B shows the deviation between the designed position coordinates and the actually measured position coordinates in a certain shot area, and the correction obtained from any one of the above-described equations (1) to (6). The quantity and the residual component after correction are schematically shown as vectors. In FIG. 2B, the vector corresponding to the deviation between the designed position coordinates and the actually measured position coordinates is “measurement data vector (indicated by a one-dot chain line)”, and the position based on the EGA statistical model is used. A vector corresponding to the coordinate correction amount is referred to as “correction amount (alignment measurement value) vector (indicated by a thick solid line)”. Therefore, a vector indicated by a solid line indicating the difference between these vectors is a vector corresponding to the corrected residual component. This vector is called a “correction result (residual) vector”. As described above, it is desirable to reduce the magnitude of the correction result vector in order to increase the overlay accuracy in the exposure apparatus 100.

  In a series of exposure operations on the wafer W, the detection result and calculation result of the wafer mark alignment detection system AS on the wafer W are stored in a storage device (not shown) as in the case of search alignment and wafer alignment. For example, the design position shift amount of the wafer mark position coordinate in the reference coordinate system detected by the alignment detection system AS, the correction parameter obtained by the statistical calculation, the center of the shot area calculated from the statistical model, The correction amount of the position coordinates, the residual component, and the like correspond to the stored data. These are hereinafter referred to as “EGA processing data”. The EGA processing data is stored in a storage device (not shown) in association with the wafer lot number, the wafer number in the lot, the shot area (shot number), and the like.

  After the wafer alignment is completed, a step-and-scan exposure operation is performed as follows. In this exposure operation, first, based on the wafer alignment result and the baseline measurement result, the XY position of the wafer W becomes the scan start position for the exposure of the first shot area (first shot) on the wafer W. As described above, the wafer stage WST is moved, and at the same time, the reticle stage RST is moved so that the Y position of the reticle R becomes the scanning start position. Then, scanning exposure is performed by irradiating illumination light IL from illumination system 10 while synchronously moving reticle stage RST and wafer stage WST, whose positions are controlled by stage controller 19.

  When the transfer of the reticle pattern to one shot area is completed in this way, wafer stage WST is moved to the scanning start position of the next shot area. At the same time, the reticle stage RST is moved to the scanning start position for the next shot area. Then, scanning exposure is performed in the same manner as in the case of the first shot area. In this manner, the movement of wafer stage WST to the scanning start position of the next shot area, the movement of reticle stage RST to the scanning start position for the next shot area, and scanning exposure are sequentially repeated, and wafer W A necessary number of shots are transferred onto the reticle R.

  When the exposure is completed, the wafer W is unloaded from the wafer stage WST by a wafer unloader (not shown) according to an instruction from the main controller 20, and then inline with the exposure apparatus 100 by a wafer transfer system (not shown). Connected to a coater / developer (not shown) (hereinafter abbreviated as “C / D”).

  The wafer W is developed within this C / D. Upon completion of the development, a transfer pattern (hereinafter referred to as “resist image”) is formed on the wafer W. Thereafter, wafer W is loaded again on wafer stage WST.

Next, the main controller 20 measures the overlay error of the shot area SA _P before layer using the alignment detection system AS, and the current developed shot area (resist image). In the circuit pattern of the reticle R, an overlay error measurement mark for measuring these overlay errors is formed. This overlay error is formed in the shot area along with the formation of the shot area (resist image). Measurement marks are also formed. Here, the amount of positional deviation between the overlay error measurement mark in the previous shot area SA _{p and} the overlay error measurement mark in the current shot area (resist layer) is represented by the previous shot area SA _p , This is measured as an overlay error with the shot area (resist image) of the current layer. The overlay error measurement data is stored in a storage device (not shown) in association with the wafer lot number, the wafer number in the lot, the shot area SA _p (shot number), and the like.

  In the exposure apparatus 100, the above-described processing is sequentially performed on each wafer of a large number of lots. In that process, EGA processing data stored in the storage device is collected and saved in an “EGA processing result file”, and overlay error measurement data is saved in a “superposition error measurement result file”. The In the present embodiment, for example, EGA processing result data and overlay error measurement data of a plurality of lots processed in one day are combined into one EGA processing result file and overlay error measurement result file, respectively, and are not shown. Stored in the storage device.

  Next, a flow for performing wafer alignment and overlay analysis / evaluation of the exposure apparatus 100 will be described. As described above, since the overlay exposure of the shot area on the wafer W is performed based on the processing result of the wafer alignment on the wafer W, it is expected that there is a close relationship between the wafer alignment and the overlay accuracy. The Therefore, in order to improve accuracy, the operator needs to analyze and evaluate wafer alignment or overlay exposure performed by the exposure apparatus 100.

The analysis and evaluation, the measurement data such as the measured position information of the wafer marks in the displacement, i.e. EGA processing coordinates of the design of each shot area SA _P on the wafer W and the measured position coordinates, EGA statistical model Is performed by causing the display device 21 to display the position coordinate correction amount based on the above, the corrected residual component, and the overlay error measurement result. In this case, the deviation between the designed position coordinates and the actually measured position coordinates, the correction amount of the position coordinates based on the EGA statistical model, and the corrected residual component may be numerically displayed. As shown in FIG. 2B, each may be displayed as a vector as a “measurement data vector”, “correction amount (alignment correction value) vector”, “correction result (residual component) vector”, or the like. Good.

  These numerical values or vectors are displayed in correspondence with each shot area on the image display of the shot area array (shot map) on the wafer. (Numeric map display). As described above, it is desirable that the correction result (residual component) vector is smaller in order to increase the accuracy of superposition. The operator refers to the vector map display (or numerical map display) superimposed on the shot map image display, analyzes and evaluates wafer alignment or overlay exposure, and analyzes and evaluates the results. The exposure apparatus 100 is adjusted based on the above.

  FIG. 3 shows an example of a screen displayed on the display device 21 when the alignment and overlay analysis / evaluation in the exposure apparatus 100 is performed. As shown in FIG. 3, this screen (alignment map window) has a “wafer shot map image display field 101” at the upper left of the screen, a “file selection field 200” on the right side thereof, and a lower side thereof from above. It is configured to include an “EGA processing result display condition setting field 300”, an “overlapping error measurement result display condition setting field 400”, and a “various button display field 500” arranged in order.

  The image display of the shot map of the wafer to be evaluated / analyzed is as described above. On the right side of the image display of the shot map of the wafer, an EGA processing result file and overlay error measurement result file selection field 200 << File Selection >> to be evaluated are displayed. In FIG. 3, the file name of the EGA processing result file with the file name “EGA-200410292044.EGAM” is displayed in the selection window. This file name is designated by the operator's text input using a keyboard (not shown). Below the file name display, additional information <File Information> such as a process program name (228USR.EGA) and a date (2004-10-29) corresponding to the file is displayed. A “Select” button is prepared on the right side of the file name of the displayed EGA processing result file. When this “Select” button is clicked with the mouse, an EGA processing result file with the file name “EGA-200410292044.EGAM” is opened, the EGA processing data therein is read into the main memory, and an EGA processing result display to be described later is displayed. In accordance with the setting in the setting column, data relating to EGA processing is displayed on a vector map display or numerical map display on the shot map image display.

  Further, below the EGA processing result file (EGAM File) selection column in the file selection column 200, a file name “MESR-200441029REG1.MESR” designated by the operator's text input using a keyboard (not shown) is superimposed. The file name of the alignment error measurement result file is displayed in the selection column. This file name is also designated by the operator's text input using a keyboard (not shown). Below the file name display, additional information <File Information> such as a process program name (228USRA.EGA) and a date (2004-10-29) corresponding to the file is displayed. A “Select” button is prepared on the right side of the file name of the displayed overlay error measurement result file. When this “Select button” is clicked by operating the mouse, the overlay error measurement result file with the file name “MESR-200441029REG1.MESR” is opened, and the data related to the overlay error is read into the main memory, which will be described later. In accordance with the setting in the display setting field for the overlay error measurement result to be performed, data relating to the overlay error is displayed on the image display 101 of the shot map as a vector map or a numerical map. As is clear from the display of <File Information>, the EGA processing result file and the overlay error measurement result file contain data for the same process (related to the results on the same layer of the same wafer W). It can be said that the result of overlay performed under the EGA process data included in the EGA process result file is included in the overlay error measurement result file.

  A selection field of “Map Display Mode” is displayed below the selection field 200 for the overlay error measurement result file. In the selection field of “Map Display Mode”, a check box for selecting the vector map “Vector map” and a check box for selecting the alignment mark map “Alignment mark map” are displayed. In the present embodiment, any one of these check boxes can be checked. In FIG. 3, the check box of the vector map is checked. Below these, a vector scale bar for changing the scale of the image display of the shot map of the wafer and a text input screen for numerical values of the scale are displayed. As a result, the operator can freely adjust the scale of the image display of the shot map of the wafer.

  Below the image display field 101 and the file selection field 200 of the wafer shot map, an EGA processing result display condition setting field 300 (a setting field where “Display File: EGA” is displayed) A display field setting field 400 (setting field displaying “Display File: MESR”) of the alignment error measurement result is displayed. To display the EGA processing result on the shot map image display of the wafer, check the check box between “Display File” and “EGA” in the EGA processing result display condition setting field 300. If the overlay error measurement result is to be displayed on the image display of the shot map of the wafer, the display of “Display File” in the display condition setting field 400 for the overlay error measurement result and “MESR” You need to check the checkbox between the display.

  In the display condition setting fields 300 and 400, check boxes for setting the EGA statistical model are displayed. This check box group includes a 6 parameter model (6-Param: first order, second order (2nd), third order model (3rd)), 10 parameter model (10-param: first order, second order (2nd), third order. Model (3rd)), when there are a large number of wafer marks attached to a shot area, an average model within a shot (Ave .: primary, secondary ( 2nd) and a cubic model (3rd)) are included. In this check box group, it is possible to check a plurality of check boxes at the same time.

  Also, under the EGA statistical model setting field, the display content of the vector map is set for each wafer (Each Wafer), for each lot (Each LOT), or for all lots (All LOT). A check box group of “Collection Components” for designating is displayed. Below that, “Display Mode” (measurement data (difference between the measured position of the center of the shot area and the design position)), correction component (alignment measurement value), and correction result (residual) are set. A check box group consisting of check boxes each specifying (component), that is, measured data, correction components, and correction results) is displayed. In this check box group, it is possible to check a plurality of check boxes simultaneously.

  Below that, no. No. 1 correction parameter setting check box group, And a check box group for setting two correction parameters. No. 1 and no. Next to 2 is a check box for enabling / disabling them. In this check box group, it is possible to check a plurality of check boxes simultaneously. In this embodiment, no. 1 and No. 2, only the check box group for setting two correction parameters is displayed. 3, no. There may be three or more check boxes for setting correction parameters. This setting field also displays a bar for designating a lot and a bar for designating a wafer. In this bar, a plurality of lots and wafers (or all of them) can be designated. ing.

  Looking at the correction parameters of this check box group individually, (Offset X, Y) first corresponds to (Cx_00, Cy_00) in the above equations (1) to (6), respectively. Checking this check box means that the value of the parameter estimated by the EGA process is used instead of (0, 0) as the value of (Cx_00, Cy_00), that is, it is valid. Means. Further, (Scaling X, Y) corresponds to (Cx_10, Cy_01) in the above equations (1) to (6), respectively. Checking this check box means that the value of the parameter estimated by the EGA process is used instead of (0, 0) as the value of (Cx_10, Cy_01), that is, it is valid. Means.

  Further, (Orthogo) corresponds to-(Cx_01 + Cy_10) in the above formulas (1) to (6). Checking this check box means that the value of the parameter estimated by EGA processing is used instead of setting the value of-(Cx_01 + Cy_10) to 0, that is, making it valid. (Rotation) corresponds to Cy_10 in the above formulas (1) to (6). Checking this check box means that the value of the parameter estimated by the EGA process is used instead of setting the value of Cy_10 to 0, that is, it is made effective. In addition, instead of-(Cx_01 + Cy_10) and Cy_10, rotation components Cx_01 and Cy_10 of each axis may be displayed in a settable manner.

  Hereinafter, (Shot scaling X, Y), (Shot Orthogo), and (Shot Rotation) correspond to (Cx_sx, Cy_sy), − (Cx_sy + Cy_sx), and Cy_sx in Expressions (4) to (6), respectively. Further, (2nd order) corresponds to (Cx_20, Cy_20, Cx_11, Cy_11, Cx_02, Cy_02) in Expression (2), Expression (3), Expression (5), and Expression (6), and (3rd order) is represented by Expression (2). This corresponds to (3) and (Cx_30, Cy_30, Cx_21, Cy_21, Cx_12, Cy_12, Cx_03, Cy_03) in Expression (6). Note that, instead of − (Cx_sy + Cy_sx) and Cy_sx, two rotation components Cx_sy and Cy_sx may be displayed in a settable manner.

  In the various button display fields 500, a “Print” button, a “Report File” button, a “Correlation Graph” button, an “Open” button, a “Save” button, a “Close” button, and the like are displayed. The “Correlation Graph” button will be described later.

  In accordance with the contents to be evaluated, the operator selects a file, a parameter model, a display mode, an EGA processing result display condition setting field 300 or an overlay error measurement result display condition setting field 400 shown in FIG. When the correction parameters of the EGA statistical model are set, the file to be evaluated is selected in the file selection field 200, and when the “Select” button is clicked, as shown in FIG. A vector map display (or numerical map display) of data relating to the EGA processing result or the overlay error measurement result is performed on the image display 101 (display process).

By the way, some items to be evaluated regarding the wafer alignment and overlay in the exposure apparatus 100 are as follows.
(1) Evaluation of correlation between EGA processing result and overlay error measurement result (2) Evaluation of appropriateness of statistical model in EGA processing (3) Evaluation of contribution of correction parameter (coefficient) of EGA statistical model (4) EGA Evaluation of correlation between measured values, correction amounts, and residual components in processing results (5) Evaluation of EGA processing results between wafers, within lots, between lots, and overlay error fluctuations (1) to (5) ) Will be described in order.

(1) Evaluation of correlation between EGA processing result and overlay result The most important thing in the exposure apparatus 100 is the overlay accuracy of shot areas between layers. Since the overlay exposure is performed based on the result of the EGA process, the EGA process is expected to have a great influence on the overlay accuracy. Therefore, the operator refers to the screen shown in FIG. 3 displayed on the display device 21 and analyzes and evaluates the correlation between the overlay error and the EGA processing result. The operator refers to the vector map (or numerical map) displayed on the image display of the shot map of the wafer W, and the overall overlay error exceeds the allowable range. If it is determined that the correlation is high, the EGA process is adjusted, and even if the overlay error is large (bad), if it is determined that the correlation between it and the EGA process is low, the overlay error is caused by the EGA process. These adjustments are made on the assumption that other factors such as the imaging characteristics of the projection optical system PL have an influence, not worsening.

  In order to determine whether or not the overlay error can be reduced by adjusting the EGA processing, it is desirable that the components included in the overlay error can be analyzed in more detail. In view of this, the main controller 20 causes the operator to analyze the component included in the overlay error when an instruction to perform the overlay error component analysis is input from the operator through the operation of the mouse or the like. It also has a function that can

  In the main controller 20, the overlay error on the wafer W is modeled by any one of the above formulas (1) to (6), and the component corresponding to the model formula in the measured value of the overlay error; Components that do not correspond to the model formula (that is, residual components) can be extracted. This extraction is realized by a process similar to the wafer alignment process described above. Which equation is selected as the model equation is determined by selecting the check box of the EGA statistical model to be selected from the EGA statistical model setting check box group in the display condition setting column of the overlay error measurement result shown in FIG. By checking, the operator can specify. The main controller 20 performs the same processing as the wafer alignment described above on the overlay error measurement data using the EGA statistical model designated by the check box setting, and designates the overlay error measurement data. A component corresponding to the model formula and other residual components are calculated, and a vector map (or numerical map) of each component can be displayed. In the present embodiment, a plurality of different EGA statistical models can be specified at the same time, and a vector map (or numerical map) of components based on each EGA statistical model can be displayed.

  Whether to display the overlay error measurement result, the component based on the specified model formula, or the other residual component is displayed in “Display Mode” in the display condition setting field 400 of the overlay error measurement result. An operator can specify by checking with a check box group (Measured Data / Collection Components / Collection Results). The main controller 20 displays a vector map (or numerical map) corresponding to the data specified by the check of the check box group. In this embodiment, two or more types of vectors are included in the overlay error measurement data, the overlay error component corresponding to the designated EGA statistical model, and the other overlay error residual components. It is possible to display the map at the same time.

  Further, in the present embodiment, it is possible to analyze / evaluate the degree of contribution to the individual overlay error of the correction parameter of any one of the above-described specified equations (1) to (6). The correction parameter for evaluating the degree of contribution is specified by the operator by checking the “Display Mode” check box group in the display condition setting field 400 for the overlay error measurement result. Main controller 20 calculates a superposition error component when only the correction parameter designated by the check of the check box is validated and a residual component other than the superposition error, and a vector of these components Display a map (or numeric map). In the present embodiment, it is possible to display a vector map (numerical map) for two or more correction parameters at the same time.

  Such a vector map (or numerical map) can be displayed not only on one wafer W, but also on a plurality of wafers W in a lot, and further on a plurality of wafers W between different lots. Is possible. In this case, by setting the Collection Contents (Each Wafer, Each LOT, All LOT) in the setting field 400 of the overlay error measurement result, the lot designation bar, and the wafer designation bar in combination, the desired lot, Data relating to the wafer can be displayed as a vector map (or as a numerical map).

  In this embodiment, as described above, it is possible to analyze a component that is expected to depend on the EGA processing of the overlay error. For comparison between the EGA processing result and the overlay error measurement result, the analysis result of this component is used. It is possible to use. That is, of the EGA processing results for the same wafer, at least one of the vectors corresponding to the measurement data, the correction amount (alignment correction value), and the correction result (residual component), and the data related to the overlay error Among them, the overlay error measurement data, the component based on the EGA statistical model of the measurement data, and at least one of the vectors corresponding to the other residual components are simultaneously displayed as a vector map (numerical map display). It is possible.

  In FIG. 3, “Display Mode” in the EGA processing setting field 300 selects an EGA residual component (Collection Results), and “Display Mode” in the overlay error measurement setting field 400 displays measurement data (Measured). Since (Data) is selected, a vector corresponding to the residual component of EGA and a vector corresponding to the overlay error measurement data are displayed in each shot area.

  FIG. 4 shows an enlarged view of an example of an image display of a wafer shot map on which the vector map at this time is displayed. As shown in FIG. 4, in each shot area of the shot map of the wafer, two vectors having the shot center as a base point are shown. Of the two vectors, the vector indicated by the solid line indicates the residual component of the EGA processing result in the shot area, and the vector indicated by the dotted line indicates the measurement data of the overlay error in the shot area. As described above, it is desirable to display the two vectors displayed at the same time by changing their attributes so that the operator can identify which one is the vector. In the vector map shown in FIG. 4, the line type of the vector indicating the EGA residual component is a solid line, and the line type of the measurement data of the overlay error is a dotted line so that the operator can discriminate both.

  In addition, in order to identify a vector, the color, the thickness, the line type, the arrow shape, and the like may be changed without being limited to the change of the line type. Further, at least one of the vectors may be blinked, and when both are blinked, the timing of the blinking may be changed by both. Alternatively, an identifier may be assigned to at least one of both vectors, and the identifier may be displayed in association with each vector so that the operator can identify the both. Such a change in the vector display can be applied to all vector map displays described later.

  The operator compares the simultaneously displayed vector map of EGA residual components (solid line) and the overlay error vector map (dotted line), and determines their correlation. In the vector map shown in FIG. 4, since there are many shot regions in which the EGA residual component vector and the overlay error vector are directed in the relatively same direction, it is considered that the degree of correlation between the two is high. It becomes possible. The high degree of correlation between the two means that the residual component of EGA is one of the major factors of overlay error. In the exposure apparatus 100, the residual component is reduced by EGA processing. It is necessary to adjust to. In order to reduce the EGA residual component, measures such as changing the EGA statistical model to a higher order or changing to a more complex model such as a multi-point model within a shot that also considers shot components are taken. Conceivable.

  As described above, the exposure apparatus 100 can simultaneously display both the vector map of the EGA processing result and the vector map of the overlay error measurement result. From this display, it is possible to determine whether or not the EGA processing result is a cause of the overlay error.

  In the present embodiment, it is possible to analyze the cause of the overlay error in more detail. For example, it is possible to analyze how much of the overlay error can be corrected by the EGA statistical model. In this case, in the example shown in FIG. 3, the “Measured Data” check box in the “Display Mode” check box group in the display condition setting field 400 of the overlay error measurement result is checked. When the “Measured Data” check box is cleared in the “Display Mode” check box group and the “Collection Components” is checked, the overlay error is measured on the shot map image of the wafer, not the overlay error itself. A vector indicating the component corresponding to the designated EGA statistical model in the data is displayed. If it is desired to display a component of the overlay error that does not correspond to the EGA statistical model, that is, a vector indicating a residual component, a check box of “Display Mode” in the display condition setting field 400 for the overlay error measurement result What is necessary is just to check "Collection Results" among groups.

  That is, in this embodiment, as in the case of FIG. 3, when comparing the EGA processing result and the overlay error measurement result, the measurement data (alignment measurement value) and the correction amount ( At least one of the alignment correction value) and the correction result (residual component) is displayed as a vector map on the image display of the wafer shot map, and not only the overlay error measurement data but also the overlay error measurement result At least one of the EGA statistical model component and the residual component in the overlay error measurement result can be displayed as a vector map on the image display of the shot map.

  As described above, in this embodiment, the data regarding the overlay error and the data regarding the EGA processing result are simultaneously displayed on the vector map, so that the correlation between the two can be visually analyzed and evaluated by the operator. If it is determined from the evaluation result that the data related to the overlay error is larger than the allowable range and the correlation between the data related to the overlay error and the EGA process data is large, the EGA process can be adjusted. it can. One such adjustment includes changing the EGA statistical model in EGA processing or adjusting the value of its correction parameter.

<Scatter plot display>
Further, when the “Correlation Graph” button displayed in the various button display column 500 is clicked with the mouse in the state shown in FIG. 3, a scatter diagram as shown in FIG. 5 is displayed. When there is a correlation between the residual component of the EGA process and the overlay error, and the correlation is a positive correlation, data is present around the straight line rising to the right as shown in FIG. It becomes a graph that is scattered. When these relationships have a negative correlation, the graph is such that the data is distributed around the right-downward straight line, and when there is no correlation, the data is such that an approximate line cannot be specified. The graph is distributed randomly. By referring to such a scatter diagram display, the operator can quantitatively and accurately analyze and evaluate the correlation between the two. Such display of a scatter diagram can be applied to all vector map displays described later.

(2) Evaluation of appropriateness of statistical model in EGA processing In the present embodiment, the appropriateness of an EGA statistical model in EGA processing can be evaluated. In the EGA statistical model (EGA Calc. Model) on the screen shown in FIG. 3, when a plurality of check boxes are checked, the main controller 20 measures the wafer alignment and includes it in the EGA processing result file. Using the measured position information of the wafer mark attached to the sample shot area, the same calculation processing (statistical processing) as the wafer alignment is performed again using the checked multiple EGA statistical models, and the value of the correction parameter And a correction amount and a residual component are calculated. Actually, for models that have been applied in EGA processing, this calculation processing has already been performed in wafer alignment, correction amounts and residual components have been calculated, and these are included in the EGA processing result file. Therefore, there is no need to perform such a calculation process again. Then, main controller 20 displays each component in a vector map (or numerical map display) according to the setting in the EGA processing result display condition setting field. For example, here, a vector map of residual components in a plurality of different EGA statistical models is displayed simultaneously. The operator can set a model having a smaller residual component as an EGA statistical model in the exposure apparatus 100 by looking at the vector map display.

  Needless to say, simultaneous display of vector maps using a plurality of different EGA statistical models can also be applied to measurement results of overlay errors. In other words, the component corresponding to a plurality of different EGA statistical models and the residual component in the measurement value of the overlay error can be simultaneously displayed as a vector map.

(3) Evaluation of Contribution of Correction Parameter of Statistical Model In this embodiment, the contribution of the correction parameter of the statistical model can be evaluated. For example, as shown in FIG. 3, in the check box group of the EGA statistical model (EGA Calc.Model) in the EGA processing result setting field 300, the above equation (1), that is, a 6-parameter primary model (6-Param) ) Is set, and No. 1 correction parameter check box group (“Collection Parameters ◇ No. 1” check box group), offset component (Offset X, Y), scaling component (Scaling X, Y), orthogonality (Orthogo), rotation ( The check boxes of the six parameters of “Rotation” are checked. In the check box group of correction parameters of No. 2 (check box group of “Collection Parameters ◇ No. 2”), only the check boxes of the scaling component (Scaling X, Y), orthogonality (Orthogo), and rotation (Rotation) are checked. Think if you are.

  In this case, the main controller 20 sets the scaling component, the orthogonality, and the rotation as the actual correction parameter values, The correction amount and correction result (residual component) for each shot area when the value of the offset component not checked with the correction parameter 2 is set to 0 are calculated. Then, as shown in FIG. 3, when “Collection Results” is checked in “Display Mode”, no. Correction results (residual components) when only the correction parameters checked in the correction parameter check box group of No. 1 are validated. The correction result (residual component) when the correction parameter value checked in the correction parameter check box group 2 is validated is simultaneously displayed as a vector map (or numerical map display).

  In this way, the contribution of the offset component to the residual component of the correction parameters can be grasped from the difference between the two vector maps displayed on the shot map image display. Similarly, for EGA parameters other than the offset component, no. 1, no. In the correction parameter check box group 2, each check box of each correction parameter to be evaluated is validated / invalidated, whereby the degree of contribution of the correction parameter to the residual component can be evaluated.

  Needless to say, the simultaneous display of the vector map (or numerical map) when at least one type of parameter is enabled / disabled can be applied to the overlay error measurement result.

  In the check box group of correction parameters in the present embodiment, one check box is provided for each of the second-order term (2nd Order) and the third-order term (3rd Order). That is, in this embodiment, if the check box of the second-order term is checked, all the second-order coefficients are valid, and if the check box of the third-order term is checked, all the third-order coefficients are valid. become. However, as shown in the above formula (2), formula (3), formula (5), formula (6), etc., there are a plurality of second-order and third-order coefficients. May be set individually.

  When the validity and invalidity of each of the second-order and third-order coefficients can be set, the contribution degree of each coefficient can be analyzed and evaluated. For example, when the above equation (2) is selected as a model equation, a vector map of residual components when the coefficients Cx_11 and Cy_11, which are terms of Wx · Wy, are enabled, and residual components when disabled When the vector map is displayed at the same time and there is almost no difference between them, the Wx / Wy term out of the quadratic terms may be excluded from the model formula. As described above, if valid / invalid can be set for each coefficient for the second-order term and the third-order term, further fine evaluation can be made for them. Therefore, an appropriate model formula with a small number of correction parameters is adopted. This is desirable from the viewpoint of accuracy and throughput.

  In this embodiment, the parameter is only set to valid or invalid, but the parameter value may be designated by text input of a keyboard (not shown).

(4) Evaluation of correlation between measurement value, correction amount, and residual component in EGA processing result In this embodiment, measurement data (alignment measurement value), correction amount (alignment correction value), correction result (residual value) in EGA processing result The correlation between the difference components) can also be evaluated. For example, in the “Display Mode” check box group of the display condition setting field 300 for the EGA processing result, if measurement data (Measured Data) and residual component (Collection Results) are checked, both of them are vector maps at the same time. Can be displayed. By displaying the measurement data and the residual component at the same time, it is possible to recognize at a glance whether or not the residual component is large because the actual measurement value of the wafer mark attached to each shot area is greatly deviated. It becomes like this. Therefore, the operator can easily find the sample shot area that should not be used for the EGA processing (that is, the sample shot area to be rejected) by looking at the simultaneous vector map display. That is, by referring to such a vector map display, the operator can confirm these correlations, and can analyze and evaluate the appropriateness of the EGA processing.

  Of course, the simultaneous display of any two vector maps among the measurement data (alignment measurement value), correction amount (alignment correction value), and correction result (residual component) can be applied to the measurement result of overlay error. is there.

<Numeric list display>
In the present embodiment, a region corresponding to each shot region (for example, a region surrounded by a circle in FIG. 6A) in the image display of the wafer shot map shown in FIG. Is specified, a numerical value list window shown in FIG. 6B is displayed. In this numerical list window, positional coordinates relating to two vectors of the designated shot area (here, CE1 and CE2 are assigned as identifiers) are displayed in a numerical list. In this numerical list display, addresses X and Y mean the design position coordinates of the wafer mark in the in-shot coordinate system of the specified shot area, that is, the position coordinates of the base point of the vector. Means the position coordinates of the end point of each vector. Below the numerical list display, an average value of dataX, Y (Total ave.) And a value three times the standard deviation (hereinafter abbreviated as “3σ”) are displayed.

(5) Evaluating fluctuations in EGA processing results and overlay results between wafers, within lots, and between lots In this embodiment, it is also possible to evaluate fluctuations in EGA processing results and overlay error measurement results across multiple lots. It is. When this evaluation is performed, for example, a pie chart shown in FIG. 7A is displayed on the screen of the display device 21. This pie chart shows the degree of variation of the EGA processing results for a plurality of wafers in lots A to G processed by the exposure apparatus 100 so far, specifically, 3σ in the correction amount and the correction result (remaining value). The ratio of each lot in the sum of 3σ of the difference component is shown. As described above, the pie chart is suitable for displaying the ratio among the statistics distribution of various data of the EGA processing result or the overlay error measurement result in each of a plurality of lots.

  Each component (region) of the pie chart shown in FIG. 7A is a pie chart showing the ratio of the variation degree of the correction parameter of the lot (lot A to lot G) corresponding to the component. Is linked to a window that displays For example, when a component of lot B indicated by a circle is clicked with a mouse, correction parameters (offset X, Y, scaling X, Y, rotation, orthogonality) in lot B as shown in FIG. It is possible to display a pie chart of the ratio of the degree of variation (3σ) between wafers of the corresponding correction amount and residual component.

  In this pie chart, the ratio of the statistic of the correction amount (variation degree) corresponding to each correction parameter of the EGA statistical model and the statistic of the residual component (variation degree) is displayed. The operator can easily confirm whether or not the ratio of the statistical amount of the residual component to the statistical amount of the correction amount is within an allowable range by looking at the ratio.

When the EGA statistical model is an in-shot multipoint model as in this embodiment, the correction parameters include a shot scaling component (Cx_sx, Cy_sy), a shot rotation component Cy_sx, a shot orthogonality − (Cx_sy + Cy_sx), and the like. It includes a plurality of types of correction parameters that define the shape of each shot area SA _P. In this case, a graph display in which the ratios of variation degrees of a plurality of types of correction parameters between shot areas in a wafer can be compared may be performed.

  This pie chart shown in FIG. 8A shows the degree of variation in the correction amount (alignment correction value) of the EGA processing for a plurality of wafers in the lot in lot A to lot G processed by the exposure apparatus 100 so far. Specifically, a pie chart showing the ratio of each lot of the sum of 3σ in the correction amount of EGA processing and 3σ of the correction result (residual component) is displayed. Each component of the pie chart shown in FIG. 8A is linked to a window that displays a pie chart showing the ratio of data variation corresponding to the correction parameter of the lot corresponding to that component. . For example, when a component of lot B indicated by a circle is clicked with a mouse, a correction amount (alignment shot correction value) for each shot in the wafer between wafers in the designated lot B as shown in FIG. 8B. Specifically, a pie chart of the ratio of each lot of the sum of the correction amount 3σ and the correction result (residual component) 3σ can be displayed. Further, each component (region) of the pie chart shown in FIG. 8B is a window displaying a pie chart showing the 3σ ratio of data corresponding to the wafer correction parameter corresponding to the component. Link to For example, when a component (region) of the wafer 1 indicated by a circle is clicked with a mouse, as shown in FIG. 8C, the correction amount corresponding to each shot-related correction parameter between shots in the wafer 1 3σ (correction amount 3σ corresponding to each of shot scaling X, Y, shot rotation, and shot orthogonality) and the residual component 3σ are displayed in a pie chart.

  Such a graph display is not limited to a pie chart. For example, a bar graph display as shown in FIG. 9 is also possible. Such a bar graph display is effective not as a comparison display of the 3σ ratios of various data of the EGA processing result or the overlay error measurement result, but as a comparison display of their absolute amounts as the distribution of statistics. Even in this case, as described above, the operator can easily confirm whether or not the ratio of the statistical amount of the residual component to the correction amount 3σ is within the allowable range.

  7B and 8C, both the correction amount 3σ corresponding to each correction parameter and the residual component 3σ are displayed, but only the correction amount 3σ corresponding to each correction parameter is displayed. May be displayed in a graph, or only 3σ of the residual component may be displayed in a graph. Further, 3σ of measurement data may be displayed.

  In the pie chart display or the bar graph display in the present embodiment, 3σ of at least two types of data among data relating to at least one of wafer alignment and overlay error is displayed, but the displayed statistics are limited to this. It may be an average value, may be an index value of the degree of variation related to standard deviation and variance, excluding 3σ, or a sum of an absolute value of the average and an index value of the degree of variation It may be.

<Summary flowchart>
FIG. 10 shows a flowchart showing the display process according to the present embodiment. This process is executed when a check box or button on the screen of the display device 21 shown in FIG. 3 is selected. As shown in FIG. 10, in step 901, the generated event (interrupt factor designated by an instruction from the operator via the keyboard or mouse) is analyzed. By analyzing this event, main controller 20 determines which of the evaluation items (1) to (6) has been designated. In the next step 903, the file selected in the file selection field shown in FIG. 3 is processed. Specifically, if it is a newly designated file, the file is opened and the data of the file is read into a main memory (not shown). In the next step 905, the check state of each check box in the check box group in the display condition setting column for the EGA processing result and overlay error measurement result, that is, the display condition is acquired.

  In the next step 907, it is determined whether recalculation of EGA or the like or calculation of statistics in the EGA processing result and overlay error measurement result is necessary for display. If this determination is affirmed, the process proceeds to step 909, and if not, the process proceeds to step 911. In the EGA processing, the correction amount and the residual component are obtained from the measurement data of the position of the sample shot area and any one of the above formulas (1) to (6), and the EGA processing result file For example, if the display condition set in the EGA processing result display condition setting field is a condition that allows the data included in the EGA processing result file to be displayed as it is, this determination is made. However, it is necessary to display data related to EGA processing in the check box group in the EGA processing result display condition setting column, and a model different from the EGA statistical model employed in wafer alignment, or some parameters This determination is affirmed if data for a model for which is disabled must be displayed. Similarly, the display condition set in the overlay error measurement result display condition setting field is a condition for displaying the data included in the overlay error measurement result file, that is, the overlay error measurement data as it is. If this is the case, this determination is denied, but it is necessary to display the component based on the EGA statistical model of the overlay error and its residual component in the check box group of the display condition setting column for the overlay error measurement result. In some cases, this determination is affirmed. In addition, this decision is always affirmed when calculating statistics.

  In the next step 909, recalculation is performed on the data related to the EGA processing result or the overlay error measurement result and needs to be recalculated, or the statistics of the EGA processing result and the overlay error measurement result are calculated. . In the calculation of statistics, statistics of two types of data in the designated EGA processing result or overlay error measurement result are calculated between lots and within lots. In step 911 performed after the determination in step 907 is denied or after execution of step 909, a vector map display (or numerical map display) of at least two types of displayed information according to the setting of the display condition setting field, A pie chart display (or bar graph display) is displayed on the screen of the display device 21. The operator refers to this display and adjusts the exposure apparatus 100 when it is necessary. After step 911 ends, the process ends, and main controller 20 returns to the event waiting state again.

  As is apparent from the above description, according to the present embodiment, the series of processing shown in FIG. 10 corresponds to the display process and the display procedure.

  As described in detail above, according to the present embodiment, at least two types of data among a plurality of types of data related to at least one of the EGA processing result and the overlay error measurement result can be simultaneously displayed on the display device 21. Therefore, it is possible for the operator to easily grasp the correlation between them.

In the present embodiment, the exposure apparatus 100 employs EGA as wafer alignment. In EGA, alignment is performed by correcting the positional information of each shot area SA _P based on the EGA statistical model of the arrangement of shot areas SA _P estimated from measured position data of several sample shot areas SA _P. In this case, the data relating to the EGA process, the measured position data of the sample shot areas SA _P, the correction amount of the position data of each shot area SA _P based on EGA statistical model, the position of the sample shot areas SA _P after correction The residual component for the actual measurement data is included. Also, the data relating to overlay error, component of the measured data of the corresponding overlay error to a plurality of correction parameters EGA statistical model and measured data of the overlay error of the shot areas SA _P, the sequence of the shot areas SA _P And the component of the measurement data of the overlay error not caused by the EGA statistical model. In the display step, since at least two types of information can be selected from the plurality of types of information and the selected information can be displayed at the same time, the contents of evaluation can be varied.

Note that in EGA processing, sample shot areas, it is necessary to select at least two shot areas SA _P. However, the number of sample shot regions, that is, the number of samples depends on the order of the selected EGA statistical model (any one of the above formulas (1) to (6)). That is, the larger the order of the model formula, the more the number of samples needs to be increased.

  According to the present embodiment, in the display step, at least two types of data among a plurality of types of data related to wafer alignment are displayed. In this way, the operator who sees the display can easily determine whether or not the two types of data are valid.

Further, according to this embodiment, in the display step, the relative at least one correction parameter for a plurality of correction parameters EGA statistical model of the arrangement of shot areas SA _P, when setting a plurality of different values each wafer Data on at least one of alignment and overlay is displayed simultaneously. In this way, the contribution degree of each correction parameter to the EGA processing result or the overlay error measurement result can be obtained, so that detailed analysis on the EGA statistical model can be performed. In this way, for example, it is possible to optimize the model, for example, by excluding correction parameters with a small contribution from the EGA statistical model.

Further, according to this embodiment, in the display step simultaneously displays the data relating to at least one of the wafer alignment and superimposition of a plurality of different statistical models of the arrangement of shot areas SA _P. In this way, EGA processing results or overlay error measurement results between different models can be compared and displayed, and the operator can easily determine which model is a model that provides good EGA processing and overlay. It will be possible to judge.

  Further, according to the present embodiment, in the display step, both data relating to wafer alignment and data relating to overlay error are displayed simultaneously. By viewing such a display, the operator can easily grasp the causal relationship between the EGA processing result and the overlay error.

  Further, according to the present embodiment, in the display step, at least two types of data among a plurality of types of data related to at least one of wafer alignment and overlay are displayed as a vector map or a numerical map. In this way, the operator can easily compare the data visually.

  Further, according to the present embodiment, in the display step, the vector attribute is changed between at least two types of data to be displayed. The vector attribute may include at least one of the color, the thickness, the line type, the arrow shape, the display state, the presence / absence of an identifier attached thereto, and the type. In this way, it is possible to prevent the operator from confusing the two types of information, and the evaluation becomes easy.

Incidentally, vector map display in the present embodiment, there was used for displaying the one vector for each shot region, as EGA statistical model, in the case of employing the shot Uchida point model, attached to the shot area SA _P Wafer marks M _{P, 1,} M _{P, 2,} M _{P, 3,} M _{P, 4} and the measured positions of the wafer marks M _{P, 1,} M _{P, 2,} M _{P, 3 ,} M _{P, 4} may be displayed as correction vectors as correction vectors. In this case, the shot area SA _P a shot map, so that the four vectors are displayed. Thus, in the case of displaying at least three vectors for the same data among the plurality of types of data relating to at least one of the wafer alignment and superimposition regarding the shot area SA _P, it connecting the end points of the at least three vectors The quadrangle formed by can also be displayed. Since each vector represents the correction amount of the position of the wafer mark M _{P, 1,} M _{P, 2,} M _{P, 3,} M _{P, 4} , the rectangle created by connecting the vectors is the shot area SA It can be seen as a manifestation of the deformation of _P itself. Thus, the operator, a change in the shape of the individual shot areas SA _P, can be grasped visually.

  Further, according to the present embodiment, in the display process, as shown in FIG. 5, a scatter diagram showing information on at least one of wafer alignment and overlay and showing the correlation between the two types of displayed data is displayed. can do. In this way, the operator can quantitatively evaluate the correlation between the two types of data.

  According to the present embodiment, in the display step, the statistical distribution of at least two types of data among a plurality of types of data related to wafer alignment or overlay is displayed in a pie chart or a bar graph. In this way, it is possible to easily compare and evaluate the statistics of two or more types of displayed data.

Incidentally, as in this embodiment, when the EGA statistical model shot Uchida point model, as correction parameters, shot scaling component, shot rotation component, the shape of each shot area SA _P such as shot perpendicularity A plurality of types of correction parameters to be defined are included. In this case, a graph display in which the distribution of statistics corresponding to a plurality of types of correction parameters among shots in the wafer can be compared may be performed. In this case, the statistics of the distributions of at least two parameters two information corresponding to each define the shape of the shot area SA _P can be graphically displayed.

  In this case, when a region corresponding to each wafer is specified in the graph display of the statistical distribution of data regarding at least two types of parameters between a plurality of wafers, the shape of the shot region on the specified wafer is changed. The distribution of statistical amounts of data corresponding to at least two types of parameters of the specified statistical model is displayed in a graph. In this way, a graph showing the statistical distribution of data corresponding to at least two types of parameters of the statistical model that defines the shape of the shot area can be called hierarchically, so that the distribution to be evaluated Can be displayed promptly, so that the efficiency of analysis and evaluation can be improved.

  In addition, as shown in FIGS. 7A, 7B, 8A, and 8B, when a plurality of wafers are managed in units of lots, within lots or between lots. The statistical distribution of at least two types of data among a plurality of types of data relating to at least one of wafer alignment and overlay error is displayed in a graph. In addition, when a component (area) corresponding to each wafer is specified in a graph display of statistical distribution of at least two kinds of data regarding at least one of wafer alignment and overlay error between lots and within a lot, Distribution distribution of data corresponding to at least two types of correction parameters in the designated linked wafer is displayed in a graph. As described above, since the graph showing the distribution of the variation of the data corresponding to the EGA parameter in each wafer collected in units of lots can be hierarchically called, the distribution to be evaluated can be quickly displayed. Therefore, the efficiency of analysis and evaluation can be improved.

  Further, according to the present embodiment, in the display step, a graph display of a statistical quantity distribution of at least two types of data among a plurality of types of data related to at least one of wafer alignment and overlay is displayed according to the display contents. You can switch to a graph or bar graph. In this way, the graph type can be matched with the type of data to be compared and displayed, and the analysis becomes easy.

  In the present embodiment, the case where EGA is performed as wafer alignment has been described. However, the present invention is not limited to this. For example, the present invention can be applied to a global alignment method other than EGA, and can also be applied to a die-by-die alignment method. For example, process deformation other than linear components, nonlinear error components due to stage grid errors, and higher order components) are not calculated for each wafer, but are measured for the first few wafers in the lot. This can be applied to an alignment method in which a high-order correction function corresponding to a high-order component obtained from the above is applied to wafers in a lot. In this case, the wafer alignment processing results or overlay error measurement results when the number of wafers from which higher order components are extracted are changed are displayed simultaneously, and the number of wafers when they are almost unchanged is displayed. The number of wafers from which higher order components are extracted may be determined.

  In addition, “Each Wafer” was checked in “Collection Contents” in the display condition setting field of the wafer alignment processing result file when this wafer alignment method was applied, and higher-order components to be corrected were changed for each wafer. In the “Collection Contents”, “Each LOT” is checked, and the residual component when the average higher-order component in a plurality of pre-selected wafers is applied to individual wafers is simultaneously vectorized. By displaying the map, it is possible to verify the averaging effect when determining the higher-order correction coefficient.

  Further, in the present embodiment, the description has been made on the assumption that the software is a software that realizes a man-machine interface function in the exposure apparatus 100 that performs display on the display device 21 of the exposure apparatus 100. As a function of application software that operates on a personal computer in a lithography system including an exposure apparatus 100 provided in a substrate processing factory, and a man-machine on an overlay measuring instrument that measures the overlay error. Of course, the present invention can be realized as a software function for realizing the interface function. That is, the present invention can be applied to all software that performs alignment and overlay evaluation.

  In the above embodiment, the higher-order component of the EGA statistical model is up to the third order. However, a model having a fourth-order or higher order component may be selected. In this case, a check box corresponding to a 4th order or higher term is provided in the correction parameter check box group in the display condition setting field shown in FIG.

  In the above embodiment, the FIA type alignment sensor is used as the alignment detection system AS. However, as described above, the laser beam is irradiated to the alignment mark in the form of a dot on the wafer W and is diffracted by the mark. The present invention can also be applied to an LSA (Laser Step Alignment) type alignment sensor that detects a mark position using scattered light, or an alignment sensor that appropriately combines the alignment sensor and the FIA method. . In addition, for example, an alignment sensor that irradiates a mark on the surface to be detected with a coherent detection light and causes two diffracted lights (for example, the same order) generated from the mark to interfere with each other is used alone, or the FIA method, the LSA. Of course, the present invention can be applied to an alignment sensor appropriately combined with a method or the like.

  In this embodiment, the overlay error between the layers is also measured by the alignment detection AS. However, if the alignment detection system AS is other than the image processing method, this overlay error is calculated. It is difficult to measure. In this case, after overlay exposure and development (or after etching), the overlay error may be measured by an overlay error measuring device provided on the lithography system. Of course, the overlay error is also compiled into overlay error measurement result files as overlay error measurement data, and the present invention can be applied.

  The alignment detection system may be an on-axis method (for example, a TTL (Through The Lens) method). In addition, the alignment detection system is not limited to the one that detects the alignment mark in a state where the alignment mark is almost stationary in the detection visual field of the alignment detection system. Relative movement may be used (for example, the aforementioned LSA system or homodyne LIA system). In the case where the detection light and the alignment mark are moved relative to each other, it is desirable that the relative movement direction is the same as the movement direction of the wafer stage WST when detecting each of the alignment marks.

  In the above embodiment, the case where the present invention is applied to a step-and-scan type scanning exposure apparatus has been described, but it is needless to say that the scope of the present invention is not limited to this. That is, it can be suitably applied to a step-and-repeat method, a step-and-stitch method, a mirror projection aligner, and a photo repeater. Further, the projection optical system PL may be any of a refraction system, a catadioptric system, and a reflection system, and may be any one of a reduction system, an equal magnification system, and an enlargement system. Further, an immersion type exposure apparatus disclosed in, for example, Japanese Patent Laid-Open No. 10-154659 and the like in which a liquid (for example, pure water) is filled between the projection optical system PL and the wafer is provided with two wafer stages. The display method of the present invention can also be suitably applied to a twin stage type exposure apparatus.

Further, although the light source of the exposure apparatus to which the present invention is applied is a KrF excimer laser, an ArF excimer laser, or an F ₂ laser, other pulse laser light sources in the vacuum ultraviolet region may be used. In addition, as the illumination light for exposure, for example, a fiber doped with erbium (or both erbium and ytterbium), for example, an infrared or visible single wavelength laser beam oscillated from a DFB semiconductor laser or fiber laser. Harmonics that are amplified by an amplifier and wavelength-converted to ultraviolet light using a nonlinear optical crystal may be used.

  An illumination optical system, a projection optical system, and an alignment detection system AS composed of a plurality of lenses are incorporated in the exposure apparatus main body, optically adjusted, and a reticle stage and wafer stage made up of a large number of mechanical parts are arranged in the exposure apparatus main body. The exposure apparatus of the above-described embodiment can be manufactured by connecting the wiring and pipes to each other and further performing general adjustment (electrical adjustment, operation check, etc.). The exposure apparatus is preferably manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  The display method of the present invention is not limited to an exposure apparatus for manufacturing a semiconductor, but is used for manufacturing an exposure apparatus and thin film magnetic head for transferring a device pattern onto a glass plate, which is used for manufacturing a display including a liquid crystal display element. The present invention can also be applied to an exposure apparatus that transfers a device pattern to be used onto a ceramic wafer, and an exposure apparatus that is used for manufacturing an image sensor (CCD, etc.), micromachine, organic EL, DNA chip, and the like. Further, in order to manufacture reticles or masks used in not only microdevices such as semiconductor elements but also light exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, electron beam exposure apparatuses, etc., glass substrates or silicon wafers, etc. The display method of the present invention can also be applied to an exposure apparatus that transfers a circuit pattern. Here, in an exposure apparatus using DUV (far ultraviolet) light, VUV (vacuum ultraviolet) light, or the like, a transmission type reticle is generally used. As a reticle substrate, quartz glass, fluorine-doped quartz glass, meteorite, Magnesium fluoride or quartz is used. Further, in a proximity type X-ray exposure apparatus or an electron beam exposure apparatus, a transmission mask (stencil mask, membrane mask) is used, and a silicon wafer or the like is used as a mask substrate.

  The semiconductor device includes a device manufacturing process, a performance design process, a reticle R manufacturing process based on the design process (mask manufacturing process), a wafer manufacturing process from a silicon material (wafer manufacturing process), The pattern of the reticle R is transferred to the wafer W by the exposure apparatus 100, and a circuit pattern is formed on the wafer W (wafer processing process), a memory repair step, and a device assembly step (including a dicing process, a bonding process, and a packaging process). It is manufactured through inspection steps and the like.

  As described above, the display method and program of the present invention are suitable for evaluating and analyzing the object alignment result and the overlay result.

It is a schematic block diagram of the exposure apparatus which concerns on one Embodiment of this invention. FIG. 2A is a diagram showing an example of the arrangement of shot areas on a wafer and wafer marks attached thereto, and FIG. 2B is an actual measurement of design position coordinates in a shot area. It is a vector diagram which shows typically the shift | offset | difference with a position coordinate, the corrected amount obtained from an EGA statistical model formula, and the residual component after correction | amendment. FIG. 6 is a view showing an example of a screen displayed on the display device 21 when performing alignment / superimposition evaluation / analysis in the exposure apparatus 100. It is a figure which shows an example of the vector map displayed on the image display of the shot map of a wafer. It is a scatter diagram which shows the correlation with an overlay error measurement result and an EGA residual component. FIG. 6A is a diagram showing an example of how an arbitrary shot area is selected from the shot map of the wafer. FIG. 6B is a numerical list display of data in the selected shot area. It is a figure which shows an example. FIG. 7A is a diagram showing an example of a pie chart display of the ratio of data statistics relating to wafer alignment or overlay results between lots, and FIG. 7B is a statistics of correction parameters in the lot. It is a figure which shows an example of the pie chart display of the ratio. FIG. 8A is a diagram showing an example of a pie chart display of the ratio of data statistics relating to wafer alignment between lots or overlay error measurement results, and FIG. 8B shows wafer alignment between wafers or FIG. 8C is a diagram showing an example of a pie chart display of the ratio of statistics of data related to the overlay error measurement result, and FIG. 8C is a diagram showing an example of a pie chart display of the ratio of statistics of correction parameters between shots. is there. It is a figure which shows an example of the bar graph display of the ratio of the statistic of the data regarding the wafer alignment between lots, or the overlay error measurement result. It is a flowchart which shows the display process in the exposure apparatus 100 which concerns on one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Illumination system, 15 ... Moving mirror, 16 ... Reticle interferometer, 17 ... Moving mirror, 18 ... Wafer laser interferometer system, 19 ... Stage controller, 20 ... Main controller, 21 ... Display device, 24 ... Wafer stage drive , 100 ... Exposure apparatus, AS ... Alignment detection system, AX ... Optical axis of projection optical system, FM ... Reference mark plate, IL ... Illumination light, PL ... Projection optical system, R ... Reticle (mask), RST ... Reticle stage , W: Wafer (object), WST: Wafer stage.

Claims (28)

Positioning and overlaying obtained when a plurality of partitioned areas arranged on at least one object are aligned with a predetermined point and a new partitioned area is formed on each partitioned area. A display method for displaying information about at least one of
A display method including a display step of simultaneously displaying at least two types of information among a plurality of types of information related to at least one of the alignment and superposition. The alignment of the object is performed by correcting the position information of each partition area based on a statistical model of the array of the partition areas estimated from the measured position information of at least two of the plurality of partition areas,
The plurality of types of information related to the alignment include information on the measured positions of the at least two partition areas, a correction amount of the position information of each partition area based on the statistical model, and each of the partition areas after the correction. And a residual component for the actual position of the position,
The plurality of types of information regarding the overlay include information regarding the actual measurement value of the overlay error, the component of the actual measurement value of the overlay error corresponding to the statistical model, and the actual measurement of the overlay error not corresponding to the statistical model. The display method according to claim 1, further comprising: a value component. In the display step,
The display method according to claim 2, wherein at least two types of information among a plurality of types of information regarding the alignment are displayed simultaneously. In the display step,
Simultaneously displaying information on at least one of the alignment and superposition when a plurality of different values are set for at least one of the plurality of types of parameters of the statistical model of the array of the partitioned areas The display method according to claim 2. In the display step,
The display method according to claim 2, wherein information regarding at least one of the alignment and superposition of a plurality of different statistical models of the array of the partition areas is simultaneously displayed. In the display step,
The display method according to claim 2, wherein both the information related to the alignment and the information related to the overlay are displayed simultaneously. In the display step,
The display according to any one of claims 1 to 6, wherein at least two kinds of information regarding at least one of the alignment and superposition are displayed in a vector map or numerically. Method. In the display step,
The display method according to claim 7, wherein the attribute of the vector is changed between at least two types of information to be displayed.   The attribute of the vector includes at least one of a color, a thickness, a type of the line, an arrow shape, a display state, the presence / absence of an identifier attached thereto, and a type. Display method of description. In the case where at least three vectors can be displayed for the same information among a plurality of types of information related to at least one of the alignment and superposition relating to the partitioned area,
The display method according to claim 9, wherein a polygon formed by connecting end points of the at least three vectors is displayed. In the display step,
The display method according to claim 1, wherein a scatter diagram showing the correlation between the at least two types of information is displayed. In the display step,
The display method according to claim 1, wherein a distribution of statistics of at least two types of information among a plurality of types of information regarding at least one of the alignment and superposition of the plurality of objects is displayed in a graph. The alignment of the object is performed by correcting the position information of each partition region based on a statistical model of the array of partition regions including a plurality of parameters defining the shape of each partition region,
In the display step,
The display method according to claim 12, wherein a distribution of statistics of information corresponding to each of at least two types of parameters defining the shape of the partition area is displayed in a graph. In the display step,
When the area corresponding to each object is specified in the graph display of the statistics distribution of the information regarding the at least two types of parameters between the plurality of objects, the shape of the partition area in the specified object is defined. The display method according to claim 13, wherein a distribution of statistical amounts of information corresponding to at least two types of parameters of the statistical model to be displayed is displayed in a graph. In the case where a plurality of the objects are managed in a predetermined number of processing units,
In the display step,
13. A statistical distribution of at least two types of information among a plurality of types of information related to at least one of the alignment and superposition within the processing unit or between the processing units is displayed in a graph. The display method according to claim 14. In the display step,
When a region corresponding to each processing unit in the graph display of the statistical distribution of at least two types of information of a plurality of types of information regarding at least one of the alignment and superposition between the processing units is specified 16. The display according to claim 15, further comprising: displaying a statistical distribution of at least two types of information among a plurality of types of information related to at least one of the alignment and superposition within the processing unit. Method. In the display step,
The display method according to any one of claims 12 to 16, wherein the distribution of statistics of the at least two types of information is displayed in a pie chart or a bar graph.   The statistical amount of at least two types of information related to at least one of the alignment and superposition is the sum of the average value, the index value of the variation degree, the absolute value of the average, and the index value of the variation degree. The display method according to claim 12, wherein the display method is any one of the following. Positioning and overlaying obtained when a plurality of partitioned areas arranged on at least one object are aligned with a predetermined point and a new partitioned area is formed on each partitioned area. A program for causing a computer to execute processing for displaying information on at least one of
A program that causes a computer to execute a display procedure for simultaneously displaying at least two types of information of a plurality of types of information related to at least one of the alignment and superposition. The alignment of the object is performed by correcting the position information of each partition area based on a statistical model of the array of the partition areas estimated from the measured position information of at least two of the plurality of partition areas,
The plurality of types of information related to the alignment include information on the measured positions of the at least two partition areas, a correction amount of the position information of each partition area based on the statistical model, and each of the partition areas after the correction. And a residual component for the actual position of the position,
The plurality of types of information regarding the overlay include information regarding the actual measurement value of the overlay error, the component of the actual measurement value of the overlay error corresponding to the statistical model, and the actual measurement of the overlay error not corresponding to the statistical model. The program according to claim 19, further comprising a value component. In the display procedure,
21. The program according to claim 20, wherein at least two types of information among the plurality of types of information regarding the alignment are displayed simultaneously. In the display procedure,
Simultaneously displaying information on at least one of the alignment and superposition when a plurality of different values are set for at least one of the plurality of types of parameters of the statistical model of the array of the partitioned areas 21. The program according to claim 20, wherein: In the display procedure,
21. The program according to claim 20, wherein information regarding at least one of the alignment and superposition of a plurality of different statistical models of the array of the partition areas is simultaneously displayed. In the display procedure,
21. The program according to claim 20, wherein both the information related to the alignment and the information related to the overlay are displayed at the same time. In the display procedure,
The program according to claim 19, wherein a statistical distribution of at least two types of information among a plurality of types of information regarding at least one of the alignment and superposition of the plurality of objects is displayed in a graph. The alignment of the object is performed by correcting the position information of each partition region based on a statistical model of the array of partition regions including a plurality of parameters defining the shape of each partition region,
In the display procedure,
26. The program according to claim 25, wherein the distribution of statistics of two pieces of information corresponding to at least two types of parameters defining the shape of the partition area is displayed in a graph. In the display procedure,
When the area corresponding to each object is specified in the graph display of the statistics distribution of the information regarding the at least two types of parameters between the plurality of objects, the shape of the partition area in the specified object is defined. 27. The program according to claim 26, wherein a statistical distribution of information corresponding to at least two kinds of parameters of the statistical model to be displayed is displayed in a graph. In the case where a plurality of the objects are managed in a predetermined number of processing units,
In the display procedure,
Displaying a distribution of statistics of at least two types of information among a plurality of types of information related to at least one of the alignment and superposition within the processing unit or between the processing units;
When a region corresponding to each processing unit in the graph display of the statistical distribution of at least two types of information of a plurality of types of information regarding at least one of the alignment and superposition between the processing units is specified 28. The distribution of statistics of at least two types of information among a plurality of types of information related to at least one of the alignment and superposition within the processing unit is displayed in a graph. A program according to any one of the above.