Method, apparatus and device for extracting contour of high-precision scanning electron microscope image

Abstract

The present application provides a method, apparatus, electronic device, and computer-readable storage medium for extracting the contour of a high-precision scanning electron microscope image. The method includes: when multiple scanning electron microscope images of multiple positions to be detected are collected, aligning the multiple scanning electron microscope images with the design layout respectively to generate an alignment result; extracting the first scanning electron microscope image contour of each scanning electron microscope image based on the alignment result; comparing each first scanning electron microscope image contour with the design layout to generate a comparison result; adjusting each first scanning electron microscope image contour based on the comparison result to generate multiple second scanning electron microscope image contours; and averaging all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour. The present application can effectively improve the accuracy of the contour of the scanning electron microscope image.

Description

Technical Field

[0001] The present application relates to the field of image contour extraction, and in particular to a method, device, electronic device and computer-readable storage medium for extracting the contour of a high-precision scanning electron microscope image. Background Art

[0002] In the manufacturing process of semiconductor integrated circuits, it is necessary to scan silicon wafers multiple times to generate a large number of scanning electron microscope (SEM) images, and through the analysis of the SEM images, each process in the manufacturing link can be judged and evaluated in a timely manner. Extracting the contour of the obtained SEM images has a very wide application in semiconductor defect detection, critical dimension measurement, and the modeling and optimization of the optical proximity effect correction (OPC) model.

[0003] Existing high-precision contour extraction schemes are as Figure 1 shown: take an SEM image with a large field of view (FOV) and containing a repeated pattern; crop multiple small SEM images containing the same pattern from the SEM image; perform alignment between all small SEM images based on the image information; average all the aligned SEM images to obtain a high-definition SEM image; extract a high-precision contour from the clear SEM image.

[0004] However, this method will limit the range of the SEM image taken to the area on the silicon wafer containing a large number of repeated patterns, and for the area that hardly contains repeated patterns, this method cannot be used to extract high-precision contours. Moreover, the high-precision contours obtained by the existing technology cannot meet the requirements of OPC model training.

[0005] Therefore, how to improve the accuracy of the contour of the scanning electron microscope image is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0006] The purpose of the present application is to provide a method, device, electronic device and computer-readable storage medium for extracting the contour of a high-precision scanning electron microscope image, which can effectively improve the accuracy of the contour of the scanning electron microscope image.

[0007] According to the first aspect of the present application, a method for extracting the contour of a high-precision scanning electron microscope image is provided. The method includes: when multiple scanning electron microscope images of multiple positions to be detected are acquired, aligning the multiple scanning electron microscope images with a design layout respectively to generate an alignment result; wherein, the multiple positions to be detected all contain the same pattern; the multiple positions to be detected correspond to the multiple scanning electron microscope images one by one;

[0008] Extracting the first scanning electron microscope image contour of each scanning electron microscope image based on the alignment result;

[0009] Comparing each first scanning electron microscope image contour with the design layout to generate a comparison result;

[0010] Adjusting each first scanning electron microscope image contour based on the comparison result to generate multiple second scanning electron microscope image contours; wherein, the multiple first scanning electron microscope image contours correspond to the multiple second scanning electron microscope image contours one by one;

[0011] Calculating the average of all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour.

[0012] Optionally, calculating the average of the second scanning electron microscope image contours to generate a third scanning electron microscope image contour includes:

[0013] Determining multiple detection points of the design layout based on the pixel size of the scanning electron microscope image;

[0014] Determining the positions of the multiple detection points on each second scanning electron microscope image contour;

[0015] Calculating the offsets between all the second scanning electron microscope image contours and the detection points at the same positions; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction;

[0016] Calculating the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction;

[0017] Determining the positions of the high-precision contour points based on the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction;

[0018] Connecting all the high-precision contour points based on the design layout to generate a third scanning electron microscope image contour.

[0019] Optionally, the multiple positions to be detected are obtained from one or more of the following ranges:

[0020] The field of view range included in the scanning electron microscope image, the range of the chip, and the range of the mask.

[0021] Optionally, in the case of collecting multiple scanning electron microscope images of multiple positions to be detected, aligning the multiple scanning electron microscope images with the design layout respectively to generate an alignment result, including:

[0022] In the case of collecting multiple scanning electron microscope images of multiple positions to be detected, extracting the fourth scanning electron microscope image contour of each scanning electron microscope image;

[0023] Adjusting the fourth scanning electron microscope image contour based on the scanning electron microscope image to generate a fifth scanning electron microscope image contour;

[0024] Converting the fifth scanning electron microscope image contour into a fifth scanning electron microscope image contour with the same format as the design layout;

[0025] Aligning the converted fifth scanning electron microscope image contour with the preset original design layout to obtain an alignment result.

[0026] Optionally, extracting the first scanning electron microscope image contour of each scanning electron microscope image based on the alignment result, including:

[0027] Adjusting the fifth scanning electron microscope image contour based on the alignment result to generate a first scanning electron microscope image contour;

[0028] Extracting each first scanning electron microscope image contour.

[0029] Optionally, comparing each first scanning electron microscope image contour with the design layout to generate a comparison result, including:

[0030] Determining multiple detection points of the design layout based on the pixel size of the scanning electron microscope image;

[0031] Determining the positions of the multiple detection points on each first scanning electron microscope image contour;

[0032] Calculating the offset between the position of each first scanning electron microscope image contour and the detection point; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction;

[0033] Calculating the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction;

[0034] Generating a comparison result based on the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction.

[0035] Optionally, after averaging all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour, the method further includes:

[0036] Calculating a critical dimension based on the third scanning electron microscope image contour; wherein, the critical dimension includes at least one of the line width and the aperture size of the third scanning electron microscope image contour;

[0037] Training an optical proximity effect correction model based on the critical dimension.

[0038] Optionally, aligning the transformed fifth scanning electron microscope image contour with a preset original design layout to obtain an alignment result, including:

[0039] Aligning the transformed fifth scanning electron microscope image contour with a preset original design layout, and obtaining an alignment result based on a preset graphic similarity index; wherein, the graphic similarity index is used to characterize the alignment degree between the fifth scanning electron microscope image contour and the design layout.

[0040] Optionally, after aligning the transformed fourth scanning electron microscope image contour with a preset original design layout to obtain an alignment result, the method further includes:

[0041] Performing automatic measurement based on the alignment result to obtain an automatic measurement result.

[0042] According to a second aspect of the present application, there is provided a high-precision scanning electron microscope image contour extraction device, the device includes:

[0043] An alignment module, configured to align multiple scanning electron microscope images with a design layout respectively to generate an alignment result when multiple scanning electron microscope images of multiple positions to be detected are collected; wherein, the multiple positions to be detected all contain the same pattern; the multiple positions to be detected correspond to the scanning electron microscope images one by one;

[0044] A first extraction module, configured to extract a first scanning electron microscope image contour of each scanning electron microscope image based on the alignment result;

[0045] A comparison module, configured to compare each first scanning electron microscope image contour with the design layout to generate a comparison result;

[0046] A first adjustment module, configured to adjust each first scanning electron microscope image contour based on the comparison result to generate multiple second scanning electron microscope image contours; wherein, the multiple first scanning electron microscope image contours correspond to the multiple second scanning electron microscope image contours one by one;

[0047] A generation module, configured to average all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour.

[0048] Optionally, a generation module, configured to determine a plurality of detection points of a design layout based on the pixel size of a scanning electron microscope image;

[0049] Determine the positions of the plurality of detection points on each of the second scanning electron microscope image contours;

[0050] Calculate the offsets between all the second scanning electron microscope image contours and the detection points at the same positions; wherein, the offsets include the offsets in the X direction and / or the Y direction;

[0051] Calculate the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction;

[0052] Determine the positions of high-precision contour points based on the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction;

[0053] Connect all the high-precision contour points based on the design layout to generate a third scanning electron microscope image contour.

[0054] Optionally, the plurality of positions to be detected can be obtained from one or more of the following ranges:

[0055] The field of view range included in the scanning electron microscope image, the range of the chip, and the range of the mask.

[0056] Optionally, an alignment module, configured to, when a plurality of scanning electron microscope images of the plurality of positions to be detected are acquired, extract a fourth scanning electron microscope image contour of each scanning electron microscope image;

[0057] Convert the fourth scanning electron microscope image contour into a fourth scanning electron microscope image contour having the same format as the design layout;

[0058] Align the converted fourth scanning electron microscope image contour with a preset original design layout to obtain an alignment result.

[0059] Optionally, a first extraction module, configured to adjust the fourth scanning electron microscope image contour based on the scanning electron microscope image;

[0060] Adjust the adjusted fourth scanning electron microscope image contour based on the alignment result to generate a first scanning electron microscope image contour;

[0061] Extract each first scanning electron microscope image contour.

[0062] Optionally, a comparison module is configured to determine a plurality of detection points of the design layout based on the pixel size of the scanning electron microscope image;

[0063] Determine the positions of the plurality of detection points on each contour of the first scanning electron microscope image;

[0064] Calculate the offset between the position of each contour of the first scanning electron microscope image and the detection point; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction;

[0065] Calculate the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction;

[0066] Generate a comparison result based on the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction.

[0067] Optionally, the apparatus further includes: a calculation module configured to calculate a critical dimension based on the contour of the third scanning electron microscope image; wherein, the critical dimension includes at least one of the line width and the aperture length of the contour of the third scanning electron microscope image;

[0068] A training module configured to train an optical proximity effect correction model based on the critical dimension.

[0069] Optionally, an alignment module is configured to align the transformed contour of the fifth scanning electron microscope image with a preset original design layout, and obtain an alignment result based on a preset graphic similarity index; wherein, the graphic similarity index is used to characterize the alignment degree between the contour of the fifth scanning electron microscope image and the design layout.

[0070] Optionally, the apparatus further includes: a measurement module configured to perform automatic measurement based on the alignment result to obtain an automatic measurement result.

[0071] According to a third aspect of the present application, there is provided an electronic device, which includes a processor, a memory, and a program or instruction stored on the memory and executable on the processor. When the program or instruction is executed by the processor, the steps of the high-precision scanning electron microscope image contour extraction method shown in the first aspect are implemented.

[0072] According to a fourth aspect of the present application, there is provided a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by the processor, the steps of the high-precision scanning electron microscope image contour extraction method shown in the first aspect are implemented.

[0073] When this application collects multiple scanning electron microscope images of multiple positions to be detected, it aligns the multiple scanning electron microscope images with the design layout respectively to generate an alignment result. Then, based on the alignment result, it extracts the first scanning electron microscope image contour of each scanning electron microscope image, compares each first scanning electron microscope image contour with the design layout to generate a comparison result, and adjusts each first scanning electron microscope image contour based on the comparison result to generate multiple second scanning electron microscope image contours; it averages all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour. After this application extracts the first scanning electron microscope image contour according to the alignment result, it compares each first scanning electron microscope image contour with the design layout, and adjusts each scanning electron microscope image through the first comparison result to form multiple second scanning electron microscope images. Among them, the multiple second scanning electron microscope images form a complete second scanning electron microscope image, and then it averages all the second scanning electron microscope images to generate a third scanning electron microscope image contour. This application can effectively improve the accuracy of the scanning electron microscope image contour. Description of the Drawings

[0074] In order to more clearly illustrate the specific embodiments of this application or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0075] Figure 1 It is a flowchart of a high-precision contour extraction method provided by the prior art;

[0076] Figure 2 It is a flowchart of a high-precision scanning electron microscope image contour extraction method provided by an embodiment of this application;

[0077] Figures 3 - 6 It is a schematic diagram of a high-precision scanning electron microscope image contour extraction method provided by an embodiment of this application;

[0078] Figure 7 It is a flowchart of a high-precision scanning electron microscope image contour extraction method provided by an embodiment of this application; and

[0079] Figure 8 It is a schematic diagram of a high-precision scanning electron microscope image contour extraction device provided by an embodiment of this application. Detailed Embodiments

[0080] To make the above and other features and advantages of the present application clearer, the present application will be further described below with reference to the accompanying drawings. It should be understood that the specific embodiments given herein are for the purpose of explaining to those skilled in the art and are merely exemplary, not restrictive.

[0081] In the following description, many specific details are set forth to provide a thorough understanding of the present application. However, it will be apparent to those of ordinary skill in the art that the present application may be practiced without the use of these specific details. In other instances, well-known steps or services have not been described in detail to avoid obscuring the present application.

[0082] Based on the content of the background art section, it can be seen that the range for taking SEM pictures in the high-precision contour extraction scheme of the prior art is limited to the area on the silicon wafer containing a large number of repeating patterns, while in the area containing almost no repeating patterns, this method cannot be used to extract high-precision contours. And the high-precision contours obtained in the prior art cannot meet the requirements of OPC model training.

[0083] To solve the above technical problems, the present application provides a high-precision scanning electron microscope image contour extraction method, device, electronic device, and computer-readable storage medium. Below, with reference to the accompanying drawings, the high-precision scanning electron microscope image contour extraction method provided by the present application will be described in detail through specific embodiments and their application scenarios.

[0084] As Figure 2 shown, the present application provides a high-precision scanning electron microscope image contour extraction method, which may include:

[0085] Step S11: When multiple scanning electron microscope images of multiple positions to be detected are acquired, align the multiple scanning electron microscope images with the design layout respectively to generate an alignment result; wherein, the multiple positions to be detected all contain the same pattern; the multiple positions to be detected correspond to the multiple scanning electron microscope images one by one.

[0086] In an optional embodiment, step S11 includes:

[0087] When multiple scanning electron microscope images of multiple positions to be detected are acquired, extract the fourth scanning electron microscope image contour of each scanning electron microscope image.

[0088] Adjust the fourth scanning electron microscope image contour based on the scanning electron microscope image to generate a fifth scanning electron microscope image contour.

[0089] Convert the fifth scanning electron microscope image contour into a fifth scanning electron microscope image contour with the same format as the design layout.

[0090] Align the contour of the converted fifth scanning electron microscope image with the preset original design layout to obtain an alignment result.

[0091] Specifically, in this application, in combination with Figure 3 and Figure 4 As shown, first, it is necessary to determine multiple positions in the silicon wafer that contain the same pattern, and then take pictures at these positions that contain the same pattern to obtain multiple scanning electron microscope images (please refer to Figure 3 ). Then, extract the fourth scanning electron microscope image contour of each scanning electron microscope image, and preliminarily adjust all the extracted fourth scanning electron microscope image contours based on the scanning electron microscope images to generate a fifth scanning electron microscope image contour; then convert the fifth scanning electron microscope image contour into a fifth scanning electron microscope image contour with the same format as the design layout. That is to say, only after converting the formats of the fifth scanning electron microscope image contour and the design layout into the same format can the two be aligned; then align the converted fifth scanning electron microscope image contour with the design layout to obtain an alignment result (please refer to Figure 4 ). This application uses two adjustments, that is, first, preliminarily adjust the fourth scanning electron microscope image contour based on the scanning electron microscope image, and then use the design layout to make a second adjustment to the fourth scanning electron microscope image contour (i.e., the fifth scanning electron microscope image contour) that has been preliminarily adjusted, so as to quickly achieve a rough alignment between the scanning electron microscope image and the design layout and accurately extract the fifth scanning electron microscope image contour.

[0092] It should be noted that the format of the fifth scanning electron microscope image contour can be GDS format / OASIS format.

[0093] In an alternative embodiment, the multiple positions to be detected are obtained from one or more of the following ranges:

[0094] The field of view range included in the scanning electron microscope image, the range of the chip, and the range of the mask.

[0095] In this embodiment, the method of extracting the contour of the scanning electron microscope image based on the design layout does not require high image quality. Therefore, the used scanning electron microscope images do not need to be cropped from the same scanning electron microscope image with a large field of view, and these images can come from the ranges of different chips and / or the ranges of masks.

[0096] It should be noted that the field of view range can be the field of view size, the range of the chip can be the chip size, and the range of the mask can be the mask size.

[0097] It should be noted that the field of view range can be smaller than the chip range and can be smaller than the mask range.

[0098] In an optional embodiment, even in an area of the same silicon wafer that does not contain a large number of repeated patterns, such as the Logic area, the pattern match algorithm can be used to find multiple positions with the same pattern, and scanning electron microscope pictures can be taken at these positions respectively. Therefore, the present application greatly expands the applicable range of the high-precision scanning electron microscope image contour extraction method.

[0099] In an optional embodiment, aligning the transformed fifth scanning electron microscope image contour with a preset original design layout to obtain an alignment result, including:

[0100] Align the transformed fifth scanning electron microscope image contour with a preset original design layout, and obtain an alignment result based on a preset graphic similarity index; wherein, the graphic similarity index is used to characterize the alignment degree between the fifth scanning electron microscope image contour and the design layout.

[0101] In an optional embodiment, after aligning the transformed fourth scanning electron microscope image contour with a preset original design layout to obtain an alignment result, the method further includes: performing automatic measurement based on the alignment result to obtain an automatic measurement result.

[0102] Step S13: Extract the first scanning electron microscope image contour of each scanning electron microscope image based on the alignment result.

[0103] In an optional embodiment, extracting the first scanning electron microscope image contour of each scanning electron microscope image based on the alignment result includes:

[0104] Adjust the fifth scanning electron microscope image contour based on the alignment result to generate the first scanning electron microscope image contour.

[0105] Extract each first scanning electron microscope image contour.

[0106] In this embodiment, after obtaining the comparison result, adjust the fifth scanning electron microscope image contour according to the comparison result to generate the first scanning electron microscope image contour, and then extract each first scanning electron microscope image contour.

[0107] Step S15: Compare each first scanning electron microscope image contour with the design layout to generate a comparison result.

[0108] In an optional embodiment, step S15 includes:

[0109] Determine multiple detection points of the design layout based on the pixel size of the scanning electron microscope image.

[0110] Determine the positions of the multiple detection points on each contour of the first scanning electron microscope image.

[0111] Calculate the offset between the position of each contour of the first scanning electron microscope image and the detection point; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction.

[0112] Calculate the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction.

[0113] Generate a comparison result based on the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction.

[0114] In this embodiment, as shown in Figure 5 Since the format of the contour of the first scanning electron microscope image has been adjusted above, that is, adjusted to the GDS format / OASIS format, therefore, the deviation value between each contour of the first scanning electron microscope image and the design layout can be directly calculated. Among them, multiple detection points of the design layout need to be determined according to the pixel size of the scanning electron microscope image, and then the positions of the corresponding detection points in each first scanning electron microscope image are found in turn, and then the offset between the position of the corresponding detection point of each contour of the first scanning electron microscope image and this detection point is calculated; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction, and this step can accurately find the offset of each first scanning electron microscope image; then calculate the average value of the X-direction offsets of all first scanning electron microscope images and / or the average value of the Y-direction offsets of all first scanning electron microscope images, and generate a comparison result according to the average value of the X-direction offsets of all first scanning electron microscope images and / or the average value of the Y-direction offsets of all first scanning electron microscope images.

[0115] It should be noted that the above offset can be an edge placement error metric. Among them, the edge placement error metric can be used to characterize the error between the edge of the simulated post-exposure photoresist pattern and the edge of the design pattern, and can be used to measure the similarity between two contours.

[0116] Step S17: Adjust each contour of the first scanning electron microscope image based on the comparison result to generate multiple contours of the second scanning electron microscope image; wherein, the multiple contours of the first scanning electron microscope image and the multiple contours of the second scanning electron microscope image correspond one by one.

[0117] Specifically, in this application, as shown in Figure 6As shown, after obtaining the above comparison results, each first scanning electron microscope image contour is adjusted according to the comparison results. That is to say, each first scanning electron microscope image contour is adjusted according to the calculated average value in the X direction and / or the average value in the Y direction to obtain a second scanning electron microscope image contour, so as to achieve precise alignment between the second scanning electron microscope image contour and the design layout contour.

[0118] Step S19: Calculate the average of all second scanning electron microscope image contours to generate a third scanning electron microscope image contour.

[0119] In an optional embodiment, an edge placement error algorithm can be used to calculate the average of all second scanning electron microscope image contours to generate a third scanning electron microscope image contour.

[0120] In an optional embodiment, step S19 includes: determining a plurality of detection points of the design layout based on the pixel size of the scanning electron microscope image.

[0121] Determine the positions of the plurality of detection points on each second scanning electron microscope image contour.

[0122] Calculate the offsets between all second scanning electron microscope image contours and the detection points at the same positions; wherein, the offsets include the offset in the X direction and / or the offset in the Y direction.

[0123] Calculate the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction.

[0124] Determine the positions of high-precision contour points based on the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction.

[0125] Connect all high-precision contour points based on the design layout to generate a third scanning electron microscope image contour.

[0126] In this embodiment, in combination with Figure 6As shown. Among them, the figure on the left is the second scanning electron microscope contour, and the figure on the right is the third scanning electron microscope contour. Among them, the second scanning electron microscope image contour includes multiple first scanning electron microscope image contours. It is necessary to determine multiple detection points of the design layout according to the pixel size of the scanning electron microscope image, then sequentially find the positions of the corresponding detection points in each scanning electron microscope image contour in the second scanning electron microscope image, and then calculate the offset between the position of the corresponding detection point in each first scanning electron microscope image contour and the detection point; among them, the offset includes the offset in the X direction and / or the offset in the Y direction. This step can accurately find the offset of each first scanning electron microscope image, and determine the position of the high-precision contour point based on the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction.

[0127] For example: The second scanning electron microscope image contour contains 3 first scanning electron microscope image contours. The coordinate position of a detection point determined in the design layout is (1, 2). The coordinates of the corresponding positions of the 3 first scanning electron microscope image contours and the detection point are (2, 7), (6, 7), and (4, 4) respectively. The average value of the offsets in the X direction is 3, and the average value of the offsets in the Y direction is 4. Therefore, the coordinate position (3, 4) is the final high-precision contour point. Finally, connect each determined high-precision contour point to obtain the third scanning electron microscope image contour, that is, the high-precision contour.

[0128] In an alternative embodiment, after averaging all the second scanning electron microscope image contours to generate the third scanning electron microscope image contour, the method further includes:

[0129] Calculating critical dimensions based on the third scanning electron microscope image contour; where the critical dimensions include at least one of the line width and the aperture size of the third scanning electron microscope image contour;

[0130] Training an optical proximity effect correction model based on the critical dimensions.

[0131] Combined Figure 7 As shown, in an alternative embodiment, the present application provides a method for extracting a high-precision scanning electron microscope image contour, and the method includes:

[0132] Select multiple positions on the silicon wafer that contain the same pattern (i.e., the above-mentioned pattern).

[0133] Take SEM images (i.e., the above-mentioned scanning electron microscope images) at the selected positions respectively.

[0134] Align all the SEM images with the design layout.

[0135] Extract the accurate GDS contours of all SEM images based on the design layout.

[0136] 0Use EPE (i.e., the above-mentioned edge placement error algorithm) to further align the GDS contours of the SEM images with the design layout.

[0137] Use EPE (i.e., the above-mentioned edge placement error algorithm) to average the aligned GDS contours to obtain a high-precision contour.

[0138] In an optional embodiment, if the high-precision contours come from different layers, the information of the multi-layer design layout can also be utilized to quickly and automatically align the high-precision contours between different layers.

[0139] Generate an alignment result. By analyzing the alignment result, the alignment status of the actual patterns between different layers can be obtained. After effective feedback, the inter-layer alignment effect of the lithography process can be improved, and the lithography process level can be enhanced.

[0140] In summary, this application introduces the information of the design layout to align the scanning electron microscope images, avoiding the direct alignment between the scanning electron microscope images. It only needs to align all the extracted scanning electron microscope image contours with the design layout respectively, which can effectively improve the efficiency of the scanning electron microscope image alignment.

[0141] In addition, this application also uses the edge placement error algorithm to perform secondary fine alignment on the scanning electron microscope image contours, further improving the accuracy of the scanning electron microscope image alignment and the precision of the contour extraction.

[0142] 5Moreover, the method of extracting the contours of the scanning electron microscope images based on the design layout in this application has low requirements for the quality of the pictures. Therefore, the used scanning electron microscope pictures do not need to be cropped from the same scanning electron microscope picture with a large field of view. These pictures can come from different Shots or Dies, greatly improving the applicable range of the high-precision scanning electron microscope image contour extraction method.

[0143] As Figure 8 shown, in an optional embodiment, this application provides a high-precision scanning electron microscope image contour extraction device, which includes:

[0144] An alignment module 81, configured to, when multiple scanning electron microscope images at multiple positions to be detected are acquired, align the multiple scanning electron microscope images with the design layout respectively to generate an alignment result; wherein, the multiple positions to be detected all contain the same pattern; the multiple positions to be detected correspond to the scanning electron microscope images one by one.

[0145] The first extraction module 82 is configured to extract the first scanning electron microscope image contour of each scanning electron microscope image based on the alignment result;

[0146] The comparison module 83 is configured to compare each first scanning electron microscope image contour with the design layout to generate a comparison result;

[0147] The first adjustment module 84 is configured to adjust each first scanning electron microscope image contour based on the comparison result to generate a plurality of second scanning electron microscope image contours; wherein, the plurality of first scanning electron microscope image contours correspond to the plurality of second scanning electron microscope image contours one by one.

[0148] The generation module 85 is configured to average all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour.

[0149] Optionally, the generation module 85 is configured to determine a plurality of detection points of the design layout based on the pixel size of the scanning electron microscope image;

[0150] Determine the positions of the plurality of detection points on each second scanning electron microscope image contour;

[0151] Calculate the offsets between all the second scanning electron microscope image contours and the detection points at the same positions; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction;

[0152] Calculate the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction;

[0153] Determine the positions of the high-precision contour points based on the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction;

[0154] Connect all the high-precision contour points based on the design layout to generate a third scanning electron microscope image contour.

[0155] Optionally, the plurality of positions to be detected can be obtained from one or more of the following ranges:

[0156] The field of view range included in the scanning electron microscope image, the range of the chip, and the range of the mask.

[0157] Optionally, the alignment module 81 is configured to extract the fourth scanning electron microscope image contour of each scanning electron microscope image when a plurality of scanning electron microscope images at a plurality of positions to be detected are acquired;

[0158] Convert the fourth scanning electron microscope image contour into a fourth scanning electron microscope image contour with the same format as the design layout;

[0159] Align the contour of the converted fourth scanning electron microscope image with a preset original design layout to obtain an alignment result.

[0160] Optionally, a first extraction module 82 is configured to adjust the contour of the fourth scanning electron microscope image based on the scanning electron microscope image;

[0161] Adjust the adjusted contour of the fourth scanning electron microscope image based on the alignment result to generate a first scanning electron microscope image contour;

[0162] Extract each first scanning electron microscope image contour.

[0163] Optionally, a comparison module 83 is configured to determine a plurality of detection points of the design layout based on the pixel size of the scanning electron microscope image;

[0164] Determine the positions of the plurality of detection points on each first scanning electron microscope image contour;

[0165] Calculate the offset between the position of each first scanning electron microscope image contour and the detection point; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction;

[0166] Calculate the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction;

[0167] Generate a comparison result based on the average value of all offsets in the X direction and / or the average value of all offsets in the Y direction.

[0168] Optionally, the apparatus further includes: a calculation module, configured to calculate a critical dimension based on the third scanning electron microscope image contour; wherein, the critical dimension includes at least one of the line width and the aperture size of the third scanning electron microscope image contour;

[0169] A training module, configured to perform optical proximity effect correction model training based on the critical dimension.

[0170] Optionally, an alignment module 81 is configured to align the contour of the converted fifth scanning electron microscope image with a preset original design layout, and obtain an alignment result based on a preset graphic similarity index; wherein, the graphic similarity index is used to characterize the alignment degree between the contour of the fifth scanning electron microscope image and the design layout.

[0171] Optionally, the apparatus further includes: a measurement module, configured to perform automatic measurement based on the alignment result to obtain an automatic measurement result.

[0172] It should be understood that each module / unit of the device of the present application can be implemented in whole or in part by software, hardware, firmware, or a combination thereof. Each module / unit can be embedded in the processor of the electronic device in the form of hardware or firmware, or independent of the processor, or can be stored in the memory of the electronic device in software form for the processor to call to execute the services of each module / unit. Each module / unit can be implemented as an independent component or module, or two or more modules / units can be implemented as a single component or module.

[0173] In one embodiment, an electronic device is provided, which includes a memory and a processor. A computer instruction executable by the processor is stored on the memory. When the computer instruction is executed by the processor, it instructs the processor to execute the steps of the method of the present application. The electronic device can generally be a server, a terminal, or any other electronic device with necessary computing and / or processing capabilities. In one embodiment, the electronic device can include a processor, a memory, a network interface, a communication interface, etc. connected through a system bus. The processor of the electronic device can be used to provide necessary computing, processing, and / or control capabilities. The memory of the electronic device can include a non-volatile storage medium and an internal memory. A service system, a computer program, etc. can be stored in or on the non-volatile storage medium. The internal memory can provide an environment for the operation of the service system and the computer program in the non-volatile storage medium. The network interface and the communication interface of the electronic device can be used to connect and communicate with external devices through a network.

[0174] The present application can be implemented as a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it causes the steps of the method of the present application to be executed. In one embodiment, the computer program is distributed on multiple network-coupled electronic devices or processors, so that the computer program is stored, accessed, and executed in a distributed manner by one or more electronic devices or processors. A single method step / service, or two or more method steps / services, can be executed by a single electronic device or processor or by two or more electronic devices or processors. One or more method steps / services can be executed by one or more electronic devices or processors, and one or more other method steps / services can be executed by one or more other electronic devices or processors. One or more electronic devices or processors can execute a single method step / service, or execute two or more method steps / services.

[0175] Those of ordinary skill in the art can understand that the steps of the method of this application can be completed by a computer program instructing relevant hardware such as electronic devices or processors. The computer program can be stored in a non-transitory computer-readable storage medium. When the computer program is executed, the steps of the method of this application are caused to be executed. Depending on the situation, any reference to a memory, storage, database, or other medium in this document may include non-volatile and / or volatile memory. Examples of non-volatile memory include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, magnetic tape, floppy disk, magneto-optical data storage device, optical data storage device, hard disk, solid state disk, etc. Examples of volatile memory include random access memory (RAM), external cache memory, etc.

[0176] The technical features described above can be combined arbitrarily. Although not all possible combinations of these technical features are described, any combination of these technical features should be considered to be covered by this specification as long as such a combination is not contradictory.

[0177] Although this application has been described in conjunction with embodiments, those skilled in the art should understand that the above description and the accompanying drawings are merely exemplary and not restrictive. This application is not limited to the disclosed embodiments. Various modifications and variations are possible without departing from the spirit of this application.

Claims

1. A method for extracting the contour of a high-precision scanning electron microscope image, characterized in that, The method includes: When multiple scanning electron microscope images of multiple positions to be detected are acquired, aligning the multiple scanning electron microscope images with a design layout respectively to generate an alignment result; wherein, the multiple positions to be detected all contain the same pattern; the multiple positions to be detected and the multiple scanning electron microscope images are in one-to-one correspondence; Extracting a first scanning electron microscope image contour of each of the scanning electron microscope images based on the alignment result; Comparing each of the first scanning electron microscope image contours with the design layout to generate a comparison result; Adjusting each of the first scanning electron microscope image contours based on the comparison result to generate multiple second scanning electron microscope image contours; wherein, the multiple first scanning electron microscope image contours and the multiple second scanning electron microscope image contours are in one-to-one correspondence; Averaging all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour.

2. The method for extracting the contour of a high-precision scanning electron microscope image according to claim 1, wherein The averaging all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour includes: Determining multiple detection points of the design layout based on the pixel size of the scanning electron microscope image; Determining the positions of the multiple detection points on each of the second scanning electron microscope image contours; Calculating the offsets between all the second scanning electron microscope image contours and the detection points at the same positions; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction; Calculating the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction; Determining the positions of high-precision contour points based on the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction; Connecting all the high-precision contour points based on the design layout to generate the third scanning electron microscope image contour.

3. The high-precision scanning electron microscope image contour extraction method according to claim 1, wherein, The multiple positions to be detected are obtained from one or more of the following ranges: The field of view range included in the scanning electron microscope image, the range of the chip, and the range of the mask.

4. The method for extracting the contour of a high-precision scanning electron microscope image according to claim 1, wherein, The aligning the multiple scanning electron microscope images with a design layout respectively to generate an alignment result when multiple scanning electron microscope images of multiple positions to be detected are acquired includes: When the multiple scanning electron microscope images of the multiple positions to be detected are acquired, extracting a fourth scanning electron microscope image contour of each of the scanning electron microscope images; Adjusting the fourth scanning electron microscope image contour based on the scanning electron microscope image to generate a fifth scanning electron microscope image contour; Converting the fifth scanning electron microscope image contour into the fifth scanning electron microscope image contour with the same format as the design layout; Aligning the converted fifth scanning electron microscope image contour with a preset original design layout to obtain the alignment result.

5. The method for extracting the contour of a high-precision scanning electron microscope image according to claim 4, characterized in that, The extracting a first scanning electron microscope image contour of each of the scanning electron microscope images based on the alignment result includes: Adjust the fifth scanning electron microscope image contour based on the alignment result to generate the first scanning electron microscope image contour; Extract each of the first scanning electron microscope image contours.

6. The method for extracting the contour of a high-precision scanning electron microscope image according to claim 1, wherein The comparison of each of the first scanning electron microscope image contours with the design layout to generate a comparison result includes: Determine multiple detection points of the design layout based on the pixel size of the scanning electron microscope image; Determine the positions of the multiple detection points on each of the first scanning electron microscope image contours; Calculate the offset between the position of each of the first scanning electron microscope image contours and the detection points; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction; Calculate the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction; Generate a comparison result based on the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction.

7. The method for extracting the contour of a high-precision scanning electron microscope image according to claim 1, characterized in that After averaging all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour, the method further includes: Calculate critical dimensions based on the third scanning electron microscope image contour; wherein, the critical dimensions include at least one of the line width and the aperture size of the third scanning electron microscope image contour; Train an optical proximity effect correction model based on the critical dimensions.

8. The method for extracting the contour of a high-precision scanning electron microscope image according to claim 4, wherein The alignment of the transformed fifth scanning electron microscope image contour with a preset original design layout to obtain an alignment result includes: Align the transformed fifth scanning electron microscope image contour with the preset original design layout, and obtain the alignment result based on a preset graphic similarity index; wherein, the graphic similarity index is used to characterize the alignment degree between the fifth scanning electron microscope image contour and the design layout.

9. The high-precision scanning electron microscope image contour extraction method according to claim 4, characterized in that After aligning the transformed fourth scanning electron microscope image contour with a preset original design layout to obtain an alignment result, the method further includes: Perform automatic measurement based on the alignment result to obtain an automatic measurement result.

10. A high-precision scanning electron microscope image contour extraction device, the device includes: An alignment module, configured to align the multiple scanning electron microscope images with a design layout respectively to generate an alignment result when multiple scanning electron microscope images at multiple positions to be detected are collected; wherein, the multiple positions to be detected all contain the same pattern; the multiple positions to be detected correspond to the scanning electron microscope images one by one; A first extraction module, configured to extract the first scanning electron microscope image contour of each of the scanning electron microscope images based on the alignment result; A comparison module, configured to compare each of the first scanning electron microscope image contours with the design layout to generate a comparison result; A first adjustment module, configured to adjust each of the first scanning electron microscope image contours based on the comparison result to generate a plurality of second scanning electron microscope image contours; wherein, the plurality of first scanning electron microscope image contours and the plurality of second scanning electron microscope image contours are in one-to-one correspondence; A generation module, configured to average all the second scanning electron microscope image contours to generate a third scanning electron microscope image contour.

11. The high-precision scanning electron microscope image contour extraction device according to claim 10, characterized in that, The generation module is configured to determine a plurality of detection points of the design layout based on the pixel size of the scanning electron microscope image; Determine the positions of the plurality of detection points on each of the second scanning electron microscope image contours; Calculate the offsets between all the second scanning electron microscope image contours and the detection points at the same positions; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction; Calculate the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction; Determine the positions of the high-precision contour points based on the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction; Connect all the high-precision contour points based on the design layout to generate the third scanning electron microscope image contour.

12. The high-precision scanning electron microscope image contour extraction device according to claim 10, characterized in that, The plurality of positions to be detected can be obtained from one or more of the following ranges: The field of view range included in the scanning electron microscope image, the range of the chip, and the range of the mask.

13. The high-precision scanning electron microscope image contour extraction device according to claim 10, characterized in that, The alignment module is configured to, when the plurality of scanning electron microscope images at the plurality of positions to be detected are acquired, extract a fourth scanning electron microscope image contour of each of the scanning electron microscope images; Adjust the fourth scanning electron microscope image contour based on the scanning electron microscope image to generate a fifth scanning electron microscope image contour; Convert the fifth scanning electron microscope image contour into the fifth scanning electron microscope image contour having the same format as the design layout; Align the converted fifth scanning electron microscope image contour with a preset original design layout to obtain the alignment result.

14. The high-precision scanning electron microscope image contour extraction device according to claim 13, wherein The first extraction module is configured to adjust the fifth scanning electron microscope image contour based on the alignment result to generate the first scanning electron microscope image contour; Extract each of the first scanning electron microscope image contours.

15. The high-precision scanning electron microscope image contour extraction device according to claim 10, wherein, The comparison module is configured to determine a plurality of detection points of the design layout based on the pixel size of the scanning electron microscope image; Determine the positions of the plurality of detection points on each of the first scanning electron microscope image contours; Calculate the offset between the position of each of the first scanning electron microscope image contours and the detection point; wherein, the offset includes the offset in the X direction and / or the offset in the Y direction; Calculate the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction; Generate a comparison result based on the average value of all the offsets in the X direction and / or the average value of all the offsets in the Y direction.

16. The high-precision scanning electron microscope image contour extraction device according to claim 10, wherein The device further includes: a calculation module, configured to calculate a critical dimension based on the contour of the third scanning electron microscope image; wherein the critical dimension includes at least one of the line width of the contour of the third scanning electron microscope image and the aperture length; a training module, configured to train an optical proximity effect correction model based on the critical dimension.

17. The high-precision scanning electron microscope image contour extraction device according to claim 13, wherein The alignment module is configured to align the transformed contour of the fifth scanning electron microscope image with the preset original design layout, and obtain the alignment result based on a preset graphic similarity index; wherein the graphic similarity index is used to characterize the alignment degree between the contour of the fifth scanning electron microscope image and the design layout.

18. The high-precision scanning electron microscope image contour extraction device according to claim 13, wherein The device further includes: a measurement module, configured to perform automatic measurement based on the alignment result to obtain an automatic measurement result.

19. An electronic device, characterized in that, The electronic device includes: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, the high-precision scanning electron microscope image contour extraction method according to any one of claims 1-9 is implemented.

20. A computer-readable storage medium, characterized in that, Computer program instructions are stored on the computer-readable storage medium, and when the computer program instructions are executed by the processor, the high-precision scanning electron microscope image contour extraction method according to any one of claims 1-9 is implemented.

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