Method and system for comparing and positioning database image by chip

Abstract

The invention provides a method and a system for comparing and positioning database images by a chip, and belongs to the field of semiconductors. The method for comparing and positioning the database images by the chip comprises the following steps of: providing a GDS original file, wherein the GDS original file comprises an original graph when an integrated circuit is designed; obtaining the key sizes of the original graphs, and screening the graphs with the key sizes of the original graphs being a first set value and a second set value respectively; etching the wafer to obtain an etched pattern; and measuring the etched pattern, obtaining the variable quantity of the critical dimension of the first pattern and the second pattern, and obtaining the compensation value of the critical dimension of the original pattern based on the variable quantity. According to the method, the key size compensation value of the graph in the GDS file is obtained in an internal difference mode, and the situation that due to different contraction or expansion sizes of the etched image of the wafer, positioning of a detection machine table fails can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a method and system for comparing and positioning a chip with a database image. Background Art

[0002] Die to Database (D2DB) refers to the process of comparing the data of integrated circuits that have been manufactured but not yet packaged with the information stored in the database. This process is very important in quality control, failure analysis, and production process optimization. For example, in the production process of chips, the etched image needs to be compared and positioned. The inspection machine or the measurement machine will have a mechanism to verify whether it has been shifted to the target position. When there is no Graphic Data Stream (GDS), an actual image needs to be taken as a reference. This image needs to be taken for different chips. Images of the same position are compared, so it is more cumbersome when operating the machine.

[0003] In the prior art, GDS can be used, and the reference part can be replaced by GDS, which can greatly reduce the time for script establishment, but the problem that follows is whether this GDS is sufficient to match the graphics to be inspected or measured. Since the GDS file can directly obtain the data of the after-development monitoring image (After Development Inspection, ADI), the ADI data does not shrink or expand, and the detection machine will not fail to position when positioning. However, after the photoresist is etched, the data of the after-etching monitoring image (After Etch Inspection, AEI) obtained will cause the detection machine to fail to position because the image after etching shrinks or expands to different sizes, which will cause the process execution to fail, or the wrong data will be measured, causing the process to fail.

[0004] It should be noted that the information disclosed in the background technology section of the invention is only intended to deepen the understanding of the general background technology of the invention, and should not be regarded as an admission or suggestion in any form that the information constitutes prior art already known to those skilled in the art. Summary of the invention

[0005] The object of the present invention is to provide a method and system for comparing and locating a chip with a database image, so as to solve the problem that the image after wafer etching fails to be positioned on a detection machine due to the different sizes of shrinkage or expansion.

[0006] In order to solve the above technical problems, the present invention provides a method for comparing and locating a chip with a database image, comprising:

[0007] Providing a GDS original file, wherein the GDS original file includes an original graphic during integrated circuit design;

[0008] Obtaining a key size of an original graphic, screening graphics whose key sizes of the original graphic are respectively a first set value and a second set value, wherein the first set value is smaller than the second set value, defining a graphic whose key size is the first set value as a first graphic, and defining a graphic whose key size is the second set value as a second graphic;

[0009] Based on the original pattern, the wafer is etched to obtain the pattern after etching;

[0010] Measuring the pattern after etching to obtain the variation of the key dimensions of the first pattern and the second pattern, and obtaining the compensation value of the key dimensions of the original pattern based on the variation;

[0011] The detection system reads the original GDS file, shrinks or expands the original pattern based on the compensation value, and then compares it with the pattern after etching to locate the measurement position.

[0012] Preferably, the target measurement range of the critical dimension is set to patterns of X1 to X2, a pattern with a critical dimension equal to X1 is defined as a first pattern, and a pattern with a critical dimension equal to X2 is defined as a second pattern.

[0013] Preferably, calculating the variation of the key dimensions of the first graphic and the second graphic comprises:

[0014] Calculate the lateral and longitudinal changes of the pattern after etching.

[0015] Preferably, calculating the variation of the key dimensions of the first graphic and the second graphic comprises:

[0016] The shrinkage or expansion of the first graphic and the second graphic relative to the original graphic in the GDS original file is calculated.

[0017] Preferably, the lateral contraction or expansion of the first graphic and the second graphic is: Wherein, Δd1 is the difference in contraction or expansion of the first pattern and the second pattern after etching compared with the original pattern in the lateral direction, and D1 is the critical dimension of the original pattern in the lateral direction;

[0018] The longitudinal contraction or expansion of the first and second figures: Wherein, Δd2 is the difference in the contraction or expansion of the first pattern and the second pattern after etching compared with the original pattern along the longitudinal direction, and D2 is the critical dimension of the original pattern along the longitudinal direction.

[0019] Preferably, obtaining the compensation value of the key dimension of the original graphic based on the variation includes:

[0020] Based on the variation, compensation values ​​of key dimensions of the original graphic along the horizontal and vertical directions are obtained by linear interpolation.

[0021] Preferably, before etching the wafer, the method further comprises:

[0022] Photoresist is coated on the surface of the wafer, and the original pattern is transferred to the surface of the photoresist by developing to obtain a developed pattern.

[0023] Preferably, obtaining the key size of the original graphic includes:

[0024] A critical dimension of a developed pattern is obtained, wherein the critical dimension of the developed pattern is equal to the critical dimension of the original pattern.

[0025] Preferably, the detection system reads the GDS original file, shrinks or expands the original pattern based on the compensation value, and compares it with the pattern after etching to locate the measurement position, including:

[0026] After the detection system reads the GDS original file, when the pattern after etching is contracted, the value of the key dimension of the original pattern is subtracted from the compensation value, or, when the pattern after etching is expanded, the value of the key dimension of the original pattern is added to the compensation value to form the new key dimension data of the original pattern;

[0027] The new critical dimension data is compared with the critical dimension of the pattern after etching to locate the measurement position.

[0028] Based on the same inventive concept, the present invention also provides a chip-to-database image comparison and positioning system, comprising:

[0029] An acquisition module is used to provide a GDS original file, wherein the GDS original file includes an original graphic when etching a wafer design;

[0030] A logic operation module is used to obtain the critical size of the original graphic, screen the graphics whose critical sizes of the original graphic are respectively the first set value and the second set value, wherein the first set value is less than the second set value, define the graphics whose critical size is the first set value as the first graphic, and define the graphics whose critical size is the second set value as the second graphic; based on the original graphic, etch the wafer to obtain the graphic after etching; measure the graphic after etching to obtain the variation of the critical sizes of the first graphic and the second graphic, and obtain the compensation value of the critical size of the original graphic based on the variation;

[0031] The detection module is used to read the original GDS file, shrink or expand the original pattern based on the compensation value, and then compare it with the pattern after etching to locate the measurement position.

[0032] Compared with the prior art, the chip-to-database image comparison and positioning method of the present invention has the following advantages:

[0033] The present invention obtains compensation values ​​by calculating the shrinkage or expansion of the graphics after etching through linear interpolation. Since the detection system only compares and matches the absolute value of the key size or the relative value of the data of the original graphics from the GDS file when matching the graphics after etching, when the amount of shrinkage or expansion of the graphics after etching is large, it can avoid the detection machine from measuring the wrong position, thereby avoiding measurement data failure and avoiding the graphics after wafer etching. The detection machine will not fail to position due to different shrinkage or expansion sizes. The accuracy of the detection machine measurement is improved.

[0034] The chip-to-database image comparison and positioning system provided by the present invention and the chip-to-database image comparison and positioning method provided by the present invention belong to the same inventive concept. Therefore, the chip-to-database image comparison and positioning system provided by the present invention has at least all the advantages of the chip-to-database image comparison and positioning method provided by the present invention, and can avoid the positioning failure of the pattern after wafer etching due to the different sizes of contraction or expansion during measurement by the detection machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flow chart of a method for comparing and locating a chip with a database image in one embodiment of the present invention;

[0036] Figure 2 is a development pattern obtained in one embodiment of the present invention;

[0037] Figure 3 is an etched pattern obtained in one embodiment of the present invention;

[0038] Figure 4 is an etched pattern obtained in another embodiment of the present invention;

[0039] Figure 5 It is the function graph of linear interpolation;

[0040] In the figure,

[0041] 10-original pattern; 20-etched pattern;

[0042] 30-Developing graphics. DETAILED DESCRIPTION

[0043] In order to make the purpose, advantages and features of the present invention clearer, the method and system for comparing and locating the chip to the database image proposed by the present invention are further described in detail in combination with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. It should be understood that the drawings in the specification do not necessarily show the specific structure of the present invention in proportion, and the illustrative features used to illustrate certain principles of the present invention in the drawings in the specification will also adopt a slightly simplified drawing method. The specific design features of the present invention disclosed herein include, for example, specific dimensions, directions, positions and shapes, which will be determined in part by the specific application and use environment. And, in the embodiments described below, sometimes the same figure mark is used in common between different drawings to represent the same part or a part with the same function, and its repeated description is omitted. In this specification, similar numbers and letters are used to represent similar items, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0044] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0045] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0046] The core idea of ​​the present invention is to provide a method and system for comparing and locating a chip with a database image, which can solve the problem of positioning failure of a detection machine due to different sizes of shrinkage or expansion of the image after wafer etching.

[0047] In order to realize the above idea, the present invention provides a method for comparing and locating a chip with a database image. Figures 1 to 5A specific implementation of a method for comparing and locating a chip with a database image is disclosed. The method for comparing and locating a chip with a database image includes the following steps S1 to S6.

[0048] Step S1: providing a GDS original file, wherein the GDS original file includes an original pattern 10 when etching a wafer design.

[0049] Specifically, refer to Figure 1 and Figure 2 As shown in FIG. 1 , the original GDS file is the design file of the integrated circuit. The GDS file includes the etching pattern of the mask when the wafer is etched, that is, the pattern layer of the etched wafer. The pattern layer includes the original pattern 10 of the etched wafer. In an ideal situation, the pattern formed after the wafer is etched is as follows: Figure 2 The structure shown in the original pattern 10 is shown in FIG. However, due to changes in process conditions, the pattern may shrink or expand after the wafer is etched.

[0050] It should be noted that in Figure 2 Figures (2a), (2b) and (2c) are three graphics with different critical dimensions.

[0051] Step S2: Obtain the critical dimensions of the original graphic 10, and filter out graphics whose critical dimensions of the original graphic 10 are respectively a first set value and a second set value, wherein the first set value is smaller than the second set value, and define the graphic whose critical dimension is the first set value as the first graphic, and define the graphic whose critical dimension is the second set value as the second graphic.

[0052] Specifically, refer to Figure 1 and Figure 2 As shown, as one embodiment, the critical dimensions of the original graphic 10 can be obtained through the data of the integrated circuit design.

[0053] As another embodiment, before etching the wafer, the method further includes: coating a photoresist on the surface of the wafer, and transferring the original pattern 10 to the surface of the photoresist by developing, so as to obtain a developed pattern 30. The wafer is a substrate surface on which a thin film to be etched is formed. Etching the wafer means etching the thin film grown on the surface of the substrate. The critical dimensions of the developed pattern 30 are approximately equal to the critical dimensions of the original pattern 10. The critical dimensions of the original pattern 10 in the GDS file can be obtained by measuring the critical dimensions of the developed pattern 30. The critical dimensions include a width CD1 along the lateral direction of the pattern and a length CD2 along the longitudinal direction. Since the developed pattern 30 formed after developing the photoresist is the same as the critical dimensions of the target pattern 10. Therefore, in this step, there is no problem of failure in positioning the detection machine.

[0054] The engineer sets the measurement range of the critical dimension to be X1-X2 as the object of detection. The graphics of the critical dimensions of the original graphics 10 are screened to be the first set value and the second set value. In this embodiment, the graphics with the critical dimension equal to X1 can be defined as the first graphics, and the graphics with the critical dimension equal to X2 can be defined as the second graphics.

[0055] It should be noted that in some other embodiments, a graphic smaller than X1 can also be used as the first graphic. At the position of the sealing ring of the wafer, a graphic with a critical size greater than X2 is used as the second graphic. In this embodiment, preferably, the graphic with a critical size equal to X1 is the first graphic. The graphic with a critical size equal to X2 is the second graphic.

[0056] Step S3: etching the wafer based on the original pattern 10 and obtaining the pattern after etching.

[0057] Specifically, refer to Figure 1 , Figure 3 and Figure 4 As shown, after etching the wafer, an etching pattern 20 is formed. The wafer is photographed by a scanning machine to obtain Figure 3 Or Figure 4 The etched pattern 20 shown. Figure 3 It can be seen that the figure has shrunk. And the amount of shrinkage varies with the size of the figure. For the original figure 10 in Figure (3a), Figure (3b) and Figure (3c), the critical dimension of the original figure 10 in Figure (3c) is greater than the critical dimension of the original figure 10 in Figure (3b). The critical dimension of the original figure 10 in Figure (3b) is greater than the critical dimension of the original figure 10 in Figure (3c). Therefore, the shrinkage of the etched figure 20 is c1>b1>a1, and c2>b2>a2. Or, as Figure 4 As shown in FIG. 1 , after etching the wafer, the etched pattern 20 expands outward. Figure 4 The expansion amount of the etched pattern 20 in the embodiment is c3>b3>a3. Whether the etched pattern shrinks or expands, it will cause the detection machine to fail in positioning.

[0058] Step S4: measuring the pattern after etching, obtaining the variation of the key dimensions of the first pattern and the second pattern, and obtaining the compensation value of the key dimension of the original pattern 10 based on the variation.

[0059] Specifically, refer to Figures 1 to 4 As shown in FIG. 1 , calculating the variation of the key dimensions of the first pattern and the second pattern includes: calculating the lateral variation and the longitudinal variation of the pattern after etching. Figure 3 As shown, not only the variation of the critical dimension CD1 in the horizontal direction is included, but also the variation of the critical dimension CD2 in the vertical direction is calculated.

[0060] Calculating the variation of the key dimensions of the first graphic and the second graphic includes calculating the shrinkage or expansion of the first graphic and the second graphic relative to the original graphic 10 in the GDS file.

[0061] The horizontal contraction or expansion of the first and second figures: Wherein, Δd1 is the difference between the first pattern and the second pattern after etching in the lateral direction of contraction or expansion compared with the original pattern 10, and D1 is the critical dimension of the original pattern 10 in the lateral direction. Figure 2 and Figure 3 As shown, (3a) can be used as the first graph. (3c) can be used as the second graph. Then, the first graph The second graphic

[0062] The longitudinal contraction or expansion of the first and second figures: Wherein, Δd2 is the difference between the first and second patterns after etching and the contraction or expansion along the longitudinal direction compared with the original pattern 10, and D2 is the critical dimension of the original pattern 10 along the longitudinal direction. Figure 3 As shown, (3a) can still be used as the first graph. (3c) can be used as the second graph. Then, the first graph

[0063] The second graphic

[0064] The values ​​H1, H2, V1 and V2 are calculated by linear interpolation to obtain the critical dimension compensation value of the pattern after etching. The specific calculation is as follows:

[0065] Ginseng Figure 5 As shown, the calculation formula of the linear interpolation method is: Y0=Y1+(Y2-Y1)×(X0-X1) / (X2-X1).

[0066] The compensation value of the pattern after etching along the lateral direction is calculated as follows:

[0067] Y1 is equal to the value of H1, Y2 is equal to the value of H2, X1 is equal to the value of CD3, and X2 is equal to the value of CD1. Then the compensation value of the pattern in the lateral direction after etching is: Y0 = H1 + (H2-H1) × (X0-CD3) / (CD1-CD3), where X0 is the value of the critical dimension of any original pattern 10 in the lateral direction. In order to distinguish it from the compensation value in the longitudinal direction of the pattern, the compensation value Y0 in the lateral direction is abbreviated as "YH".

[0068] The compensation value of the pattern after etching along the longitudinal direction is calculated as follows:

[0069] Y1 is equal to the value of V1, Y2 is equal to the value of V2, X1 is equal to the value of CD4, and X2 is equal to the value of CD2. Then the compensation value of the pattern in the longitudinal direction after etching is: Y0 = V1 + (V2-V1) × (X0-CD4) / (CD2-CD4), where X0 is the value of the critical dimension of any original pattern 10 in the longitudinal direction. In order to distinguish it from the compensation value in the transverse direction of the pattern, the compensation value Y0 in the longitudinal direction is abbreviated as "YV".

[0070] Step S5: The detection system reads the GDS original file, shrinks or expands the original pattern 10 based on the compensation value, and then compares it with the pattern after etching to locate the measurement position.

[0071] Specifically, refer to Figure 1 As shown, when the inspection machine compares the graphics after etching, the GDS original file is first read through the inspection system. When the graphics after etching are contracted, the value of the key dimension of the original graphics 10 is subtracted from the compensation value, or, when the graphics after etching are expanded, the value of the key dimension of the original graphics 10 is added to the compensation value to form the new key dimension data of the original graphics 10, so that the new key dimension data of the original graphics 10 can be obtained. When the graphics after etching are contracted, the value of the key dimension of the original graphics 10 along the horizontal direction is subtracted from the value of the compensation value YH, and the value of the key dimension of the original graphics 10 along the vertical direction is subtracted from the value of the compensation value YV to obtain the new key dimension data of the original graphics. When the graphics after etching are expanded, the value of the key dimension of the original graphics 10 along the horizontal direction is added to the value of YH, and the value of the key dimension of the original graphics 10 along the vertical direction is added to the value of the compensation value YV to obtain the new key dimension data of the original graphics. After the wafer is etched, the pattern after etching is obtained, and then the new critical dimension data of the original pattern is compared with the critical dimension data of the pattern after etching to locate the measurement position.

[0072] The compensation value is obtained by calculating the shrinkage or expansion of the graphics after etching through linear interpolation. Since the detection system only compares and matches the absolute value of the key size or the relative value of the data of the original graphics from the GDS file when matching the graphics after etching, when the graphics after etching shrink or expand by a large amount, it can avoid the detection machine from measuring the wrong position, thereby avoiding measurement data failure and preventing the graphics after wafer etching from failing to position the detection machine due to different shrinkage or expansion sizes. The accuracy of the detection machine measurement is improved.

[0073] To realize the above idea, the embodiment also discloses a chip-to-database image comparison and positioning system, including an acquisition module for providing a GDS original file, wherein the GDS original file includes the original graphics when etching the wafer design; a logic operation module for acquiring the critical dimensions of the original graphics, screening the graphics whose critical dimensions of the original graphics are respectively a first set value and a second set value, wherein the first set value is less than the second set value, and the graphics whose critical dimensions are the first set value are defined as the first graphics, and the graphics whose critical dimensions are the second set value are defined as the second graphics; based on the original graphics, etching the wafer to obtain the graphics after etching; measuring the graphics after etching to obtain the change in the critical dimensions of the first graphics and the second graphics, and based on the change, obtaining the compensation value of the critical dimensions of the original graphics; a detection module for reading the GDS original file, and shrinking or expanding the original graphics based on the compensation value, and then comparing it with the graphics after etching to locate the measurement position.

[0074] The chip-to-database image comparison and positioning system provided in this embodiment and the chip-to-database image comparison and positioning method provided in this embodiment belong to the same inventive concept. Therefore, the chip-to-database image comparison and positioning system provided in this embodiment has at least all the advantages of the chip-to-database image comparison and positioning method provided in this embodiment, and can avoid the failure of the detection machine to position the graphics after wafer etching due to the different sizes of contraction or expansion.

[0075] In summary, the above embodiments provide detailed descriptions of different configurations of the method and system for comparing and positioning images between chips and databases. Of course, the above description is only a description of the preferred embodiments of the present invention, and is not any limitation to the scope of the present invention. The present invention includes but is not limited to the configurations listed in the above embodiments. Those skilled in the art can draw inferences based on the contents of the above embodiments. Any changes and modifications made by those of ordinary skill in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A method for comparing and locating a chip with a database image, characterized in that: include: Providing a GDS original file, wherein the GDS original file includes an original graphic during integrated circuit design; Obtaining a key size of an original graphic, screening graphics whose key sizes of the original graphic are respectively a first set value and a second set value, wherein the first set value is smaller than the second set value, defining a graphic whose key size is the first set value as a first graphic, and defining a graphic whose key size is the second set value as a second graphic; Based on the original pattern, the wafer is etched to obtain the pattern after etching; Measuring the pattern after etching to obtain the variation of the key dimensions of the first pattern and the second pattern, and obtaining the compensation value of the key dimensions of the original pattern based on the variation; The detection system reads the original GDS file, shrinks or expands the original pattern based on the compensation value, and then compares it with the pattern after etching to locate the measurement position.

2. The method for comparing and locating a chip with a database image according to claim 1, characterized in that: The target measurement range of the critical dimension is set to be a pattern of X1 to X2, a pattern with a critical dimension equal to X1 is defined as a first pattern, and a pattern with a critical dimension equal to X2 is defined as a second pattern.

3. The method for comparing and locating a chip with a database image according to claim 1, characterized in that: Calculating the change in the critical dimensions of the first graphic and the second graphic includes: Calculate the lateral and longitudinal changes of the pattern after etching.

4. The method for comparing and locating a chip with a database image according to claim 1, characterized in that: Calculating the change in the critical dimensions of the first graphic and the second graphic includes: The shrinkage or expansion of the first graphic and the second graphic relative to the original graphic in the GDS original file is calculated.

5. The method for comparing and locating a chip with a database image according to claim 4, characterized in that: The horizontal contraction or expansion of the first and second figures: Wherein, Δd1 is the difference in contraction or expansion of the first pattern and the second pattern after etching compared with the original pattern in the lateral direction, and D1 is the critical dimension of the original pattern in the lateral direction; The longitudinal contraction or expansion of the first and second figures: Wherein, Δd2 is the difference in the contraction or expansion of the first pattern and the second pattern after etching compared with the original pattern along the longitudinal direction, and D2 is the critical dimension of the original pattern along the longitudinal direction.

6. The method for comparing and locating a chip with a database image according to claim 1, characterized in that: Based on the variation, the compensation value of the key dimension of the original graphic is obtained including: Based on the variation, compensation values ​​of key dimensions of the original graphic along the horizontal and vertical directions are obtained by linear interpolation.

7. The method for comparing and locating a chip with a database image according to claim 1, characterized in that: Before etching the wafer, the method further comprises: Photoresist is coated on the surface of the wafer, and the original pattern is transferred to the surface of the photoresist by developing to obtain a developed pattern.

8. The method for comparing and locating a chip with a database image according to claim 7, characterized in that: The key dimensions for obtaining the original image include: A critical dimension of a developed pattern is obtained, wherein the critical dimension of the developed pattern is equal to the critical dimension of the original pattern.

9. The method for comparing and locating a chip with a database image according to claim 1, characterized in that: The detection system reads the original GDS file, shrinks or expands the original pattern based on the compensation value, and compares it with the pattern after etching to locate the measurement position, including: After the detection system reads the GDS original file, when the pattern after etching is contracted, the value of the key dimension of the original pattern is subtracted from the compensation value, or, when the pattern after etching is expanded, the value of the key dimension of the original pattern is added to the compensation value to form the new key dimension data of the original pattern; The new critical dimension data is compared with the critical dimension of the pattern after etching to locate the measurement position.

10. A chip-to-database image comparison and positioning system, characterized in that: include: An acquisition module is used to provide a GDS original file, wherein the GDS original file includes an original graphic when etching a wafer design; A logic operation module is used to obtain the critical size of the original graphic, screen the graphics whose critical sizes of the original graphic are respectively the first set value and the second set value, wherein the first set value is less than the second set value, define the graphics whose critical size is the first set value as the first graphic, and define the graphics whose critical size is the second set value as the second graphic; based on the original graphic, etch the wafer to obtain the graphic after etching; measure the graphic after etching to obtain the variation of the critical sizes of the first graphic and the second graphic, and obtain the compensation value of the critical size of the original graphic based on the variation; The detection module is used to read the original GDS file, shrink or expand the original pattern based on the compensation value, and then compare it with the pattern after etching to locate the measurement position.

Images