Optical proximity correction method
By performing optical proximity correction on the initial main pattern and the redundant pattern respectively, the periodically arranged initial redundant units are obtained and replaced, which solves the problems of long OPC running time and high layout complexity and achieves more efficient optical proximity correction.
Patent Information
- Application Number
- CN202410331362.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-21
- Publication Date
- 2025-09-23
AI Technical Summary
The optical proximity correction method in the prior art causes the OPC running time to be too long, and the insertion of redundant graphics increases the layout complexity and OPC resource usage.
Optical proximity correction is performed on the initial main pattern and the initial redundant pattern respectively. The first optical proximity correction is performed by obtaining periodically arranged initial redundant units and replacing the initial redundant units with the corrected redundant units, thereby reducing the complexity and operation time of the optical proximity correction process.
The optical proximity correction step is simplified, the OPC operation time is reduced, the layout pattern complexity is reduced, and the efficiency of the etching and chemical mechanical polishing processes is improved.
Smart Images
Figure CN120686530A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to an optical proximity correction method. Background Art
[0002] In semiconductor manufacturing, as design dimensions continue to shrink, the optical proximity effect (OPE) caused by the exposure system becomes increasingly severe. To address this, optical proximity correction (OPC) is used to correct errors during the photolithography process. This involves pre-processing the mask before photolithography to achieve pre-correction, ensuring that the amount of correction is just enough to compensate for the optical proximity effect caused by the exposure system. After photolithography, the mask created from the OPC-corrected layout can produce the desired target pattern on the wafer.
[0003] At the same time, as design dimensions continue to shrink, the uniformity of pattern density distribution has a significant impact on the etching process and chemical mechanical polishing process. In the case of uneven pattern density distribution, it is easy to aggravate the loading effect during etching, causing the final size of some patterns to deviate from the target size, and it is more likely to cause the pattern to be over-polished during the chemical mechanical polishing process. To this end, the traditional practice is to insert redundant patterns (dummy inserting) in the blank area around the main pattern in the layout to achieve uniform pattern density.
[0004] However, the insertion of redundant graphics makes the layout graphics more complicated. Both redundant graphics and main graphics participate in the calculation during the OPC process. A large number of redundant graphics will occupy too much OPC resources and running time.
[0005] Therefore, a new optical proximity correction method is urgently needed to reduce the OPC running time. Summary of the Invention
[0006] The technical problem solved by the present invention is to provide an optical proximity correction method to reduce the OPC running time.
[0007] To solve the above problems, the technical solution of the present invention provides an optical proximity correction method, comprising: providing an initial layout, the initial layout including a main graphic area and a redundant graphic area surrounding the main graphic area, the main graphic area having a plurality of initial main graphics, and the redundant graphic area having a plurality of initial redundant graphics; dividing the plurality of initial redundant graphics within the redundant graphic area to obtain a plurality of periodically arranged initial redundant units; taking any of the initial redundant units as a target redundant unit, performing a first optical proximity correction to obtain a corrected redundant unit, the corrected redundant unit including a plurality of first corrected redundant graphics, the first corrected redundant graphics corresponding to the initial redundant graphics of the target redundant unit; replacing the corresponding initial redundant units with the plurality of corrected redundant units respectively to obtain a target layout.
[0008] Optionally, the method further includes: performing a second optical proximity correction on the main graphic area of the initial layout to obtain a second revised layout, wherein the second revised layout includes a plurality of revised main graphics, and the revised main graphics correspond to the initial main graphics.
[0009] Optionally, the method for acquiring the target layout further includes: in the initial layout, replacing the corresponding initial main graphic with each of the modified main graphics.
[0010] Optionally, the method for obtaining a corrected redundant unit includes: obtaining an area to be corrected within the redundant graphic area, the area to be corrected including the target redundant unit; performing the first optical proximity correction on the area to be corrected to obtain a first corrected layout, the first corrected layout including the corrected redundant unit.
[0011] Optionally, the area to be corrected further includes: a plurality of adjacent graphics, and the plurality of adjacent graphics are located around the target redundant unit.
[0012] Optionally, the first revised layout further includes: a plurality of second revised redundant graphics corresponding to the adjacent graphics.
[0013] Optionally, the method for obtaining the area to be corrected in the redundant graphic area also includes: establishing an auxiliary area in the redundant graphic area around the target redundant unit, taking the auxiliary area and the redundant graphic area where the target redundant unit is located as the area to be corrected, and taking the initial redundant graphic in the auxiliary area as the adjacent graphic.
[0014] Optionally, pattern density values of the plurality of initial main patterns and the plurality of initial redundant patterns are within a preset range.
[0015] Accordingly, the technical solution of the present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned graphics correction method when executing the computer program.
[0016] Accordingly, the technical solution of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the above-mentioned graphics correction method are implemented.
[0017] Compared with the prior art, the technical solution of the present invention has the following advantages:
[0018] In the optical proximity correction method of the technical solution of the present invention, optical proximity correction is performed on the initial main pattern and the initial redundant pattern respectively, which is beneficial to reducing the complexity of the layout pattern during a single optical proximity correction process and reducing the OPC operation time; at the same time, according to the periodic arrangement rule of several initial redundant patterns in the redundant pattern area, several initial redundant patterns in a single period (i.e., a single initial redundant unit) are obtained as target redundant units to perform a first optical proximity correction, and the corrected redundant units are used to replace each of the initial redundant units to obtain the target layout. There is no need to perform optical proximity correction on all the initial redundant patterns, which further helps to reduce the OPC operation time. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 is a flow chart of an optical proximity correction method according to an embodiment of the present invention;
[0020] Figures 2 to 6 1 is a schematic structural diagram of each step of the optical proximity correction method in an embodiment of the present invention. DETAILED DESCRIPTION
[0021] As mentioned in the background art, the OPC running time in the prior art is too long, and a new optical proximity correction method is urgently needed to simplify the optical proximity correction steps and save OPC running time.
[0022] In order to solve the above problems, the present invention provides an optical proximity correction method, which performs optical proximity correction on the initial main pattern and the initial redundant pattern respectively, which is beneficial to reducing the complexity of the layout pattern during a single optical proximity correction process and reducing the OPC operation time; at the same time, according to the periodic arrangement rule of several initial redundant patterns in the redundant pattern area, several initial redundant patterns in a single period (i.e., a single initial redundant unit) are obtained as target redundant units to perform a first optical proximity correction, and the corrected redundant units are used to replace each of the initial redundant units to obtain the target layout. There is no need to perform optical proximity correction on all the initial redundant patterns, which further helps to reduce the OPC operation time.
[0023] In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.
[0024] Figure 1 2 is a flow chart of an optical proximity correction method according to an embodiment of the present invention.
[0025] Please refer to Figure 1 , the optical proximity correction method comprises the following steps:
[0026] Step S101, providing an initial layout, the initial layout including a main graphic area and a redundant graphic area surrounding the main graphic area, the main graphic area having a plurality of initial main graphics, and the redundant graphic area having a plurality of initial redundant graphics;
[0027] Step S102, dividing the plurality of initial redundant patterns in the redundant pattern area to obtain a plurality of periodically arranged initial redundant units;
[0028] Step S103, taking any of the initial redundant units as a target redundant unit;
[0029] Step S104, performing a first optical proximity correction on the target redundant unit to obtain a corrected redundant unit, wherein the corrected redundant unit includes a plurality of first corrected redundant patterns, and the first corrected redundant patterns correspond to the initial redundant pattern of the target redundant unit;
[0030] In step S105 , the corresponding initial redundant cells are replaced by a plurality of the modified redundant cells to obtain a target layout.
[0031] The following is a detailed description with reference to the accompanying drawings.
[0032] Figures 2 to 6 1 is a schematic structural diagram of each step of the optical proximity correction method in an embodiment of the present invention.
[0033] Please refer to Figure 2 , providing an initial layout, the initial layout including a main graphic area M and a redundant graphic area D surrounding the main graphic area M, the main graphic area M having several initial main graphics 101, and the redundant graphic area D having several initial redundant graphics 102.
[0034] In this embodiment, the pattern density values of the initial main patterns 101 and the initial redundant patterns 102 are within a preset range. The purpose of setting the preset range is to ensure a uniform pattern density distribution in the final revised layout, thereby suppressing the loading effect during the etching process and reducing the probability of defects during the chemical mechanical polishing process.
[0035] Please refer to Figure 3, dividing a plurality of the initial redundant patterns 102 in the redundant pattern area D to obtain a plurality of periodically arranged initial redundant cells Cell-i.
[0036] Subsequently, any of the initial redundant units Cell-i is used as the target redundant unit Cell-1, and a first optical proximity correction is performed on the target redundant unit Cell-1 to obtain a corrected redundant unit, wherein the corrected redundant unit includes several first corrected redundant graphics, and the first corrected redundant graphics correspond to the initial redundant graphics 102 of the target redundant unit.
[0037] In this embodiment, the method for obtaining the modified redundant unit can be found in Figures 4 and 5 .
[0038] Please refer to Figure 4 , and continue to refer to Figure 3 , obtaining a to-be-corrected area D00 in the redundant graphic area D, wherein the to-be-corrected area D00 includes the target redundant cell Cell-1.
[0039] In this embodiment, the area to be corrected D00 further includes: a plurality of adjacent patterns 103, which are located around the target redundant cell Cell-1. The adjacent patterns 103 are used to simulate the environment of the redundant cell Cell-1 within the redundant pattern area D, thereby improving the accuracy of the correction of the target redundant cell Cell-1.
[0040] In this embodiment, the method for obtaining the area to be corrected D00 in the redundant graphic area D also includes: establishing an auxiliary area (not shown in the figure) in the redundant graphic area D around the target redundant unit Cell-1, and using the auxiliary area and the redundant graphic area D where the target redundant unit Cell-1 is located as the area to be corrected D00, and using the initial redundant graphic 102 in the auxiliary area as the adjacent graphic 103.
[0041] Please refer to Figure 5 , perform the first optical proximity correction on the area to be corrected D00 to obtain a first correction layout D11, the first correction layout D11 includes a correction redundant unit Cell-2, the correction redundant unit Cell-2 includes a plurality of first correction redundant graphics 202, and the first correction redundant graphics 202 correspond to the initial redundant graphics 102 of the target redundant unit Cell-1.
[0042] The first revised layout D11 further includes: a plurality of second revised redundant graphics 203 corresponding to the adjacent graphics 103 .
[0043] Please refer to Figure 6, a number of the modified redundant cells Cell-2 are used to replace the corresponding initial redundant cells Cell-i to obtain the target layout.
[0044] At this point, optical proximity correction is performed on the initial main pattern 101 and the initial redundant pattern 102 respectively, which is beneficial to reducing the complexity of the layout pattern during a single optical proximity correction process and reducing the OPC operation time; at the same time, according to the periodic arrangement rule of the multiple initial redundant patterns 102 in the redundant pattern area, multiple initial redundant patterns 102 in a single period (i.e., a single initial redundant unit Cell-i) are obtained as the target redundant unit Cell-1 to perform the first optical proximity correction, and the corrected redundant unit Cell-2 is used to replace each of the initial redundant units Cell-i to obtain the target layout. There is no need to perform optical proximity correction on all the initial redundant patterns 102, which is further beneficial to reducing the OPC operation time.
[0045] In this embodiment, a second optical proximity correction is also performed on the main graphic area M of the initial layout to obtain a second corrected layout (not shown in the figure). The second corrected layout includes several corrected main graphics 201, and the corrected main graphics 201 correspond to the initial main graphics 101.
[0046] In this embodiment, the method for acquiring the target layout further includes: in the initial layout, replacing the corresponding initial main graphic 101 with each of the modified main graphics 201 .
[0047] Correspondingly, an embodiment of the present invention further provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned graphics correction method when executing the computer program.
[0048] Accordingly, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the optical proximity correction method described above are implemented.
[0049] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the claims.
Claims
1. An optical proximity correction method, characterized in that: include: Providing an initial layout, the initial layout comprising a main graphic area and a redundant graphic area surrounding the main graphic area, the main graphic area having a plurality of initial main graphics, and the redundant graphic area having a plurality of initial redundant graphics; Dividing a plurality of the initial redundant patterns in the redundant pattern area to obtain a plurality of periodically arranged initial redundant units; Taking any of the initial redundant units as a target redundant unit, performing a first optical proximity correction to obtain a corrected redundant unit, wherein the corrected redundant unit includes a plurality of first corrected redundant patterns, and the first corrected redundant patterns correspond to the initial redundant pattern of the target redundant unit; The corresponding initial redundant cells are replaced by a plurality of the modified redundant cells to obtain a target layout.
2. The optical proximity correction method according to claim 1, wherein: Also includes: A second optical proximity correction is performed on the main graphic area of the initial layout to obtain a second revised layout, wherein the second revised layout includes a plurality of revised main graphics, and the revised main graphics correspond to the initial main graphics.
3. The optical proximity correction method according to claim 2, wherein: The method for acquiring the target layout further includes: in the initial layout, replacing the corresponding initial main graphic with each of the modified main graphics.
4. The optical proximity correction method according to claim 1, wherein: The method for obtaining a corrected redundant unit includes: obtaining an area to be corrected in the redundant graphic area, the area to be corrected including the target redundant unit; performing the first optical proximity correction on the area to be corrected to obtain a first corrected layout, the first corrected layout including the corrected redundant unit.
5. The optical proximity correction method according to claim 4, wherein: The area to be corrected further includes: a plurality of adjacent graphics, and the plurality of adjacent graphics are located around the target redundant unit.
6. The optical proximity correction method according to claim 5, wherein: The first revised layout further includes: a plurality of second revised redundant graphics corresponding to the adjacent graphics.
7. The optical proximity correction method according to claim 5, wherein: The method for obtaining the area to be corrected in the redundant graphic area also includes: establishing an auxiliary area in the redundant graphic area around the target redundant unit, using the auxiliary area and the redundant graphic area where the target redundant unit is located as the area to be corrected, and using the initial redundant graphic in the auxiliary area as the adjacent graphic.
8. The optical proximity correction method according to claim 1, wherein: The pattern density values of the plurality of initial main patterns and the plurality of initial redundant patterns are within a preset range.
9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the image correction method according to any one of claims 1 to 8 are implemented.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the optical proximity correction method according to any one of claims 1 to 8 are implemented.