Method for processing and correcting mask weakpoint, storage medium and electronic equipment
By dividing the mask pattern into sub-pictures and matching search corrections in the weakness graphic library, the problem of weakness discovery and repair in the mask design is solved, and the weakness repair before the mask is achieved, and the yield of the mask is improved. and productivity.
Patent Information
- Application Number
- CN202411339864.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-25
- Publication Date
- 2024-12-31
AI Technical Summary
In the prior art, it is difficult for light mask design manufacturers to effectively discover and repair weaknesses, resulting in an increase in the risk of unqualified light mask production and a lack of prevention mechanisms. It is necessary to wait until the light mask production is completed before problems are discovered.
Before making the mask, divide the mask pattern into multiple sub-pictures, and perform matching searches in the weakness graphics library. Correct the matching graphics rules according to the matching graphics rules. If new graphics are found, add them to the graphics library to ensure that Fix weaknesses before making.
By quickly searching and correcting weaknesses in the mask pattern, reducing construction periods are delayed, ensuring timely production and supply of chips, and improving the yield of the mask.
Smart Images
Figure CN119226560A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of semiconductor mask manufacturing, and in particular to a method for processing and correcting weakpoints of a mask, a storage medium, and an electronic device. Background Art
[0002] In the semiconductor field, in order to transfer a circuit pattern onto a silicon wafer, it is necessary to first perform a layout design based on the circuit pattern, design a mask pattern, then make a mask based on the mask pattern, and finally transfer the pattern on the mask to the silicon wafer.
[0003] With the development of technology, the size of circuits on silicon wafers is getting smaller and smaller, and the requirements for masks are getting higher and higher. The quality of the mask directly affects the yield of the chip.
[0004] Optical Proximity Correction (OPC) can be performed during layout design. The layout processed by OPC will be verified before making the mask, that is, the graphics processed by OPC will be simulated and calculated to determine whether they meet the requirements of the process window. The process window refers to a range of process parameter values within which the circuit pattern on the manufactured silicon wafer can meet the requirements of the design specifications. The process window defines the range of parameter fluctuations that can be tolerated during the manufacturing process. Points that do not meet the process window requirements are called weakpoints.
[0005] However, in actual production, after the mask designer finds the weakpoint, there is no effective way to fix it, and it needs to be handed over to the mask manufacturer for repair. Or for the designer, it takes too long to repair the weakpoint, so he gives up the repair. Moreover, for the manufacturer, even for some common weakpoints, it is difficult to find all the weakpoints before production, which increases the risk of unqualified mask production. There is a lack of prevention mechanism, and it may be necessary to wait until the mask is completed before finding out whether the mask is qualified.
[0006] For mask manufacturers, how to discover weakpoints and repair them before production is a technical problem to be solved by this application. Summary of the invention
[0007] The purpose of the present application is to provide a method for processing and correcting weakpoints of a photomask, a storage medium, and an electronic device, so as to help photomask manufacturers to discover weakpoints and repair them before production.
[0008] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions.
[0009] In a first aspect, an embodiment of the present application provides a method for processing and correcting a weakpoint of a mask, which is used to correct a weakpoint in a mask pattern. The method for processing and correcting a weakpoint of a mask comprises:
[0010] Before the mask is made, the mask pattern is divided into multiple sub-images;
[0011] A corresponding matching search is performed for each of the sub-images in the weakpoint graphics library. When there is a target sub-image that matches any graphic to be corrected in the weakpoint graphics library, the target sub-image is corrected according to the correction rule corresponding to the graphic to be corrected.
[0012] Optionally, the method for processing and correcting the mask weakpoint further includes:
[0013] After the mask production is completed, it is determined whether there is a new pattern that needs to be corrected according to the mask production result;
[0014] If a new pattern that needs to be corrected is found according to the mask production result, the new pattern that needs to be corrected is added to the weakpoint pattern library.
[0015] Optionally, the step of dividing the mask pattern into a plurality of sub-images includes:
[0016] The mask pattern is divided at least twice into at least two groups of sub-images, wherein the edge of one group of sub-images is located at a non-edge position of another group of sub-images.
[0017] Optionally, among the at least two groups of sub-pictures, a center of one group of sub-pictures is located at an edge of another group of sub-pictures.
[0018] Optionally, among the at least two groups of sub-pictures, the center of one group of sub-pictures is located at the midpoint of the edge of another group of sub-pictures.
[0019] Optionally, any of the graphics to be corrected includes a main concerned graphic;
[0020] The steps of performing corresponding matching searches in the weakpoint graphic library for each of the sub-pictures include:
[0021] The sub-images are matched according to the main concerned graphics in the graphics to be corrected.
[0022] Optionally, the main concerned graphic is provided with a corresponding first similarity threshold;
[0023] According to the main concerned figure in the figure to be corrected, the step of matching the sub-image comprises:
[0024] When the graphic to be corrected includes only the main concerned graphic, the similarity between the main concerned graphic in the graphic to be corrected and the graphic in the sub-picture is calculated, and when there is a sub-picture whose similarity reaches the first similarity threshold, the sub-picture is determined to be a target sub-picture that matches the graphic to be corrected.
[0025] Optionally, some of the graphics to be corrected further include graphics of secondary concern; the graphics of secondary concern are provided with corresponding second similarity thresholds; in any of the graphics to be corrected, the second similarity threshold is less than the first similarity threshold;
[0026] The steps of performing corresponding matching searches in the weakpoint graphic library for each of the sub-pictures include:
[0027] When the graphic to be corrected includes a secondary concern graphic, a first similarity between the primary concern graphic of the graphic to be corrected and the graphic in the sub-picture is calculated, and a second similarity between the secondary concern graphic of the graphic to be corrected and the graphic in the sub-picture is calculated. When there is a sub-picture whose first similarity reaches the first similarity threshold and whose second similarity reaches the second similarity threshold, the sub-picture is determined to be a target sub-picture that matches the graphic to be corrected.
[0028] In a second aspect, an embodiment of the present application provides a computer-readable storage medium, in which a computer program or instruction is stored. When the computer program or instruction is executed by a computer, the method for processing and correcting the weakpoint of the mask of the first aspect is implemented.
[0029] In a third aspect, an embodiment of the present application provides an electronic device, comprising a memory and a processor, wherein the memory is electrically connected to the processor, a computer program is stored in the memory, and when the processor executes the computer program, the method for correcting the mask weakpoint of the first aspect is implemented.
[0030] Compared with the prior art, this application has the following beneficial effects:
[0031] The method for processing and correcting the weakpoint of the mask provided in the embodiment of the present application can quickly search and correct the graphics that need to be corrected in the mask pattern, complete the production of qualified masks earlier, avoid the extension of the construction period, and facilitate the timely production and supply of chips. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0033] Figure 1 A schematic diagram of an electronic device provided in an embodiment of the present application;
[0034] Figure 2 A schematic flow chart of a method for processing and correcting a mask weakpoint provided in an embodiment of the present application;
[0035] Figure 3 A schematic diagram of two groups of cut sub-pictures provided in an embodiment of the present application, in which the edge of a first group of sub-pictures is located at a non-edge position of a second group of sub-pictures;
[0036] Figure 4 A schematic diagram of two groups of cut sub-pictures provided in an embodiment of the present application, in which the longitudinal edge of the first group of sub-pictures is the central axis of the second group of sub-pictures;
[0037] Figure 5 A schematic diagram of two groups of cut sub-images provided in an embodiment of the present application, in which the horizontal edge of the first group of sub-images is the central axis of the third group of sub-images;
[0038] Figure 6 A schematic diagram of a method of cutting out two groups of sub-pictures provided in an embodiment of the present application, in which the center of the second group of sub-pictures is located at the midpoint of the edge of the first group of sub-pictures;
[0039] Figure 7 A schematic diagram of a target graphic obtained by correction provided in an embodiment of the present application;
[0040] Figure 8 Based on Figure 7 The obtained schematic diagram of the graphics to be corrected;
[0041] Fig. 9 A schematic diagram of a mask production process without using a mask weakpoint processing correction method;
[0042] Fig.10 Schematic diagram of the mask production process using the mask weakpoint processing correction method. DETAILED DESCRIPTION
[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. The described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described in the drawings here can be arranged and designed in various different configurations.
[0044] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.
[0045] In the description of this application, it should be noted that relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium.
[0046] like Figure 1 , which is a block diagram of an electronic device 10 provided in an embodiment of the present application. The electronic device 10 includes a memory 11 and a processor 12.
[0047] The memory 11 and the processor 12 are electrically connected to each other directly or indirectly to achieve data transmission or interaction. For example, these elements can be electrically connected to each other through one or more communication buses or signal lines. The memory 11 stores computer programs or instructions, and the processor 12 executes various functional applications and data processing by running the software programs and modules stored in the memory 11, that is, the processing and correction method of the mask weakpoint in the embodiment of the present application is realized.
[0048] Understandably, Figure 1 The structure shown is for illustration only. The electronic device 10 may also include Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown. Figure 1 Each component shown in the figure can be implemented by hardware, software or a combination thereof.
[0049] The embodiment of the present application further provides a readable storage medium, the readable storage medium comprising a computer program. When the computer program is executed, the electronic device 10 where the readable storage medium is located is controlled to execute a method for processing and correcting a mask weakpoint.
[0050] Before executing the mask weakpoint processing correction method, a weakpoint graphics library can be pre-stored. The weakpoint graphics library includes graphics to be corrected saved in the form of pictures. The graphics to be corrected can be set based on experience, and can be weakpoint graphics to be corrected obtained based on past mask production and chip production processes.
[0051] For example, according to experience, a 9-sided pattern in the mask pattern design will eventually affect the silicon wafer yield, and converting the 9-sided pattern into a pentagon can avoid the impact on the silicon wafer yield. Therefore, the 9-sided pattern is included in the weakpoint graphic library, and the conversion method of the pentagon converted from the 9-sided pattern is stored as a correction rule. Then, even if the mask pattern provided by the mask design manufacturer contains tens of thousands of such 9-sided patterns, the mask obtained after the mask weakpoint processing correction method will no longer have such 9-sided patterns, and will not affect the silicon wafer yield in the future.
[0052] If tens of thousands of such 9-gons are modified one by one, it will take a lot of time. The mask weakpoint processing and correction method can quickly search and correct the graphics that need to be corrected in the mask pattern, complete the production of qualified masks earlier, avoid the extension of construction period, and facilitate the timely production and supply of chips.
[0053] See also Figure 2 , is a flow chart of a method for processing and correcting a mask weakpoint provided in an embodiment of the present application, the method for processing and correcting a mask weakpoint includes:
[0054] Step 1: Before making the mask, the mask pattern is divided into multiple sub-images;
[0055] Step 2: Perform a corresponding matching search for each sub-image in the weakpoint graphics library. When there is a target sub-image that matches any graphics to be corrected in the weakpoint graphics library, correct the target sub-image according to the correction rule corresponding to the graphics to be corrected.
[0056] Regarding the correction rules, the correction rules can be to uniformly correct the graphics of multiple similar target sub-images into the same target graphic; the correction rules can also be to modify the local size of the graphics of a target sub-image to form a new graphic, such as widening a narrow position. Moreover, the correction rules are only for the graphics in this sub-image and will not affect other graphics, thus avoiding other points from becoming weak points and affecting the yield of silicon wafers.
[0057] In step 1, there are many ways to cut the mask pattern into multiple sub-images. The pattern can be cut into rectangles or squares, or into sub-images of other shapes. The pattern can be cut into at least two groups of sub-images, and the size of the sub-images cut each time can also be different. Several different cutting methods are listed below.
[0058] The mask pattern can be cut at least twice, such as Figure 3 , the dotted line indicates the edge position of the first group of sub-pictures, and the solid line indicates the edge position of the second group of sub-pictures. The edge of the first group of sub-pictures is located at the non-edge position of the second group of sub-pictures.
[0059] This can prevent the edge of one group of word images from cutting into the graphics that need to be corrected. If the graphics that need to be corrected are on two adjacent but independent sub-images, it will result in the inability to match these two sub-images to the graphics that need to be corrected in the weakpoint graphics library in step 2. The other group of sub-images does not cut into the graphics that need to be corrected, so the other group of sub-images can match the graphics that need to be corrected in the weakpoint graphics library.
[0060] In order to better prevent cutting into the graphics that need to be corrected, the center of one group of sub-pictures can be located at the edge of another group of sub-pictures, such as Figure 4 (The dotted line indicates the edge position of the first group of sub-pictures, and the solid line indicates the edge position of the second group of sub-pictures). The longitudinal edge of the first group of sub-pictures is the central axis of the second group of sub-pictures. The transverse edge of the first group of sub-pictures can coincide with the transverse edge of the second group of sub-pictures. The second group of sub-pictures can prevent the longitudinal edge of the first group of sub-pictures from cutting into the graphics that need to be corrected.
[0061] Corresponding to the horizontal edge of the first group of sub-pictures, a third group of sub-pictures can also be cut out, such as Figure 5 , the dotted line represents the edge position of the first group of sub-pictures, and the thick dotted line represents the edge position of the third group of sub-pictures. Then the horizontal edge of the first group of sub-pictures is the central axis of the third group of sub-pictures. The third group of sub-pictures can prevent the horizontal edge of the first group of sub-pictures from cutting into the graphics that need to be corrected.
[0062] The size of the sub-image can be determined according to the size of the graphics to be corrected in the weakpoint graphics library, and the sub-image size can be set to be n times larger than the size of the largest graphics to be corrected.
[0063] Figure 6 A two-step segmentation method is shown. The dotted lines indicate the edge positions of the first group of sub-images, and the solid lines indicate the edge positions of the second group of sub-images. The vertical and horizontal edges of the first group of sub-images are both the central axes of the second group of sub-images, and the center of the second group of sub-images is located at the midpoint of the edge of the first group of sub-images. In this way, only two segmentations are required to prevent the horizontal and vertical edges of the first group of sub-images from cutting into the graphics that need to be corrected.
[0064] After the sub-images are obtained by segmentation, graphics can be extracted from the sub-images and compared with the graphics to be corrected in the weakpoint graphics library. Each graphic to be corrected includes a primary graphics of concern, and some graphics to be corrected may also include secondary graphics of concern. Regarding the corresponding matching search in the weakpoint graphics library for each sub-image in step 2, for some graphics to be corrected, the secondary graphics of concern can be ignored, and the sub-images are matched only according to the primary graphics of concern in the graphics to be corrected. After matching, correction is performed according to the correction rules of the graphics to be corrected.
[0065] When a graphic to be corrected includes a main concerned graphic, a similarity threshold corresponding to the main concerned graphic can be set. When the similarity between the graphic in the sub-picture and the main concerned graphic of a graphic to be corrected reaches the similarity threshold, the sub-picture is determined to match the graphic to be corrected.
[0066] When a graphic to be corrected includes a graphic of primary concern and a graphic of secondary concern, a similarity threshold corresponding to the graphic of secondary concern may also be set, the similarity threshold corresponding to the graphic of primary concern is a first similarity threshold, and the similarity threshold corresponding to the graphic of secondary concern is a second similarity threshold. In each graphic to be corrected, the first similarity threshold is greater than the second similarity threshold. For example, the first similarity threshold is 80% or 90%, and the second similarity threshold is 0 or 30%. For a sub-image, the first similarity between the graphic of primary concern of the graphic to be corrected and the graphic in the sub-image is calculated, and the second similarity between the graphic of secondary concern of the graphic to be corrected and the graphic in the sub-image is calculated. When there is a sub-image whose first similarity reaches the first similarity threshold and whose second similarity reaches the second similarity threshold, the sub-image is determined to be a target sub-image that matches the graphic to be corrected.
[0067] Setting the similarity threshold can also add new graphics to be corrected to the weakpoint graphics library: according to the graphics to be corrected and the similarity threshold, the graphics to be corrected can be transformed to obtain new graphics to be corrected. Or according to the similarity threshold, the corrected target graphics can be transformed to obtain new graphics to be corrected and added to the weakpoint graphics library.
[0068] like Figure 7 , Figure 7 The target graph obtained by correction according to the correction rule is shown, which includes the main concerned graph 1 and two secondary concerned graphs 2. After a certain similarity threshold transformation, it can be obtained Figure 8 The graphics shown need to be corrected and added to the weakpoint graphics library.
[0069] In addition, the graphics to be corrected in the weakpoint graphics library can be classified according to the layer type of the mask, and different mask layer types have different graphics to be corrected. The mask pattern can include multiple mask layer type patterns, and each mask layer type pattern is divided into sub-pictures for matching.
[0070] After correcting all target sub-images obtained by a round of matching search for each sub-image, a new mask pattern is obtained. Mask production using the new mask pattern can avoid the occurrence of weak points of the mask pattern before correction.
[0071] If new graphics that need to be corrected are found after the mask production is completed, the new graphics that need to be corrected can be added to the weakpoint graphics library.
[0072] like Fig. 9 If the method for processing and correcting the weakpoint of the mask provided in the embodiment of the present application is not adopted, it is necessary to inspect the mask after the mask is produced to obtain the weakpoint, and then it is necessary to modify the weakpoint and re-produce the mask.
[0073] like Fig.10 If the method for processing and correcting the weakpoint of the photomask provided in the embodiment of the present application is adopted, that is, matching search is performed before the photomask is produced, the weakpoint is corrected, and then the photomask is produced, the yield of the photomask is greatly improved and the cost is saved. If there is still a weakpoint, the weakpoint graphic library can be added to avoid the weakpoint in the subsequent produced photomask.
[0074] The above-described device and system embodiments are merely illustrative, and some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. A person of ordinary skill in the art may understand and implement the present embodiment without creative effort.
[0075] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.
Claims
1. A method for processing and correcting a mask weakpoint, characterized in that: include: Before the mask is made, the mask pattern is divided into multiple sub-images; A corresponding matching search is performed for each of the sub-images in the weakpoint graphics library. When there is a target sub-image that matches any graphic to be corrected in the weakpoint graphics library, the target sub-image is corrected according to the correction rule corresponding to the graphic to be corrected.
2. The method for correcting a mask weakpoint according to claim 1, wherein: The method for processing and correcting the mask weakpoint also includes: After the mask production is completed, it is determined whether there is a new pattern that needs to be corrected according to the mask production result; If a new pattern that needs to be corrected is found according to the mask production result, the new pattern that needs to be corrected is added to the weakpoint pattern library.
3. The method for correcting a mask weakpoint according to claim 1, wherein: The steps of dividing the mask pattern into a plurality of sub-images include: The mask pattern is divided at least twice into at least two groups of sub-images, wherein the edge of one group of sub-images is located at a non-edge position of another group of sub-images.
4. The method for correcting a mask weakpoint according to claim 3, wherein: Among the at least two groups of sub-pictures, the center of one group of sub-pictures is located at the edge of another group of sub-pictures.
5. The method for correcting a mask weakpoint according to claim 4, wherein: Among the at least two groups of sub-pictures, the center of one group of sub-pictures is located at the midpoint of the edge of another group of sub-pictures.
6. The method for correcting a mask weakpoint according to claim 1, wherein: Any of the graphics to be corrected includes a main concerned graphic; The steps of performing corresponding matching searches in the weakpoint graphic library for each of the sub-pictures include: The sub-images are matched according to the main concerned graphics in the graphics to be corrected.
7. The method for correcting a mask weakpoint according to claim 6, wherein: The main concerned graphic is provided with a corresponding first similarity threshold; According to the main concerned figure in the figure to be corrected, the step of matching the sub-image comprises: When the graphic to be corrected includes only the main concerned graphic, the similarity between the main concerned graphic in the graphic to be corrected and the graphic in the sub-picture is calculated, and when there is a sub-picture whose similarity reaches the first similarity threshold, the sub-picture is determined to be a target sub-picture that matches the graphic to be corrected.
8. The method for correcting a mask weakpoint according to claim 7, wherein: Some of the graphics to be corrected also include graphics of secondary concern; the graphics of secondary concern are provided with corresponding second similarity thresholds; in any of the graphics to be corrected, the second similarity threshold is less than the first similarity threshold; The steps of performing corresponding matching searches in the weakpoint graphic library for each of the sub-pictures include: When the graphic to be corrected includes a secondary concern graphic, a first similarity between the primary concern graphic of the graphic to be corrected and the graphic in the sub-picture is calculated, and a second similarity between the secondary concern graphic of the graphic to be corrected and the graphic in the sub-picture is calculated. When there is a sub-picture whose first similarity reaches the first similarity threshold and whose second similarity reaches the second similarity threshold, the sub-picture is determined to be a target sub-picture that matches the graphic to be corrected.
9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program or instruction. When the computer program or instruction is executed by a computer, the method for processing and correcting a weakpoint of a photomask according to any one of claims 1 to 8 is implemented.
10. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory is electrically connected to the processor, a computer program is stored in the memory, and when the processor executes the computer program, the method for processing and correcting a mask weakpoint according to any one of claims 1 to 8 is implemented.