Optical proximity correction method

Abstract

An optical proximity correction method, a first correction layout is obtained, the first correction layout includes a first correction edge and a second correction edge; a first exposure processing is performed on the first correction layout to obtain a first exposure layout, the first exposure layout includes a first exposure edge and a second exposure edge; a target layout is provided, the target layout includes a first target edge and a second target edge; a first edge placement error between the first exposure edge and the first target edge and a second edge placement error between the second exposure edge and the second target edge are obtained, the first edge placement error is greater than a preset edge placement error range, and the second edge placement error is within the preset edge placement error range; the first correction edge is translated by using optical proximity correction to make the first edge placement error within the preset edge placement error range, the second correction edge is translated to keep a first interval size equal to a mask regular size, and the second edge placement error is within the preset edge placement error range, so that the correction precision is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and more specifically to an optical proximity correction method. Background Technology

[0002] Photolithography is a crucial technology in semiconductor manufacturing. It transfers patterns from a photomask to the surface of a silicon wafer, forming semiconductor products that meet design requirements. The photolithography process includes an exposure step, a development step following exposure, and an etching step following development. In the exposure step, light passes through the light-transmitting areas of the photomask and shines onto the silicon wafer coated with photoresist, causing a chemical reaction in the photoresist. In the development step, the different solubility of the developer in the photoresist and the non-photoresist is used to form a photolithographic pattern, transferring the photomask pattern onto the photoresist. In the etching step, the silicon wafer is etched based on the photolithographic pattern formed by the photoresist layer, further transferring the photomask pattern onto the silicon wafer.

[0003] In semiconductor manufacturing, as design dimensions continue to shrink and approach the limits of photolithography imaging systems, the diffraction effect of light becomes increasingly pronounced, leading to optical image degradation of the final design pattern. The actual photolithographic pattern formed is severely distorted relative to the pattern on the mask, resulting in a difference between the actual pattern formed on the silicon wafer and the design pattern. This phenomenon is called the Optical Proximity Effect (OPE).

[0004] To correct the optical proximity effect, Optical Proximity Correction (OPC) was developed. The core idea of ​​OPC is to establish an OPC model based on the consideration of counteracting the optical proximity effect. The photomask pattern is designed according to the OPC model. In this way, although the lithographic pattern and the corresponding photomask pattern have an optical proximity effect, the cancellation of this phenomenon has been considered when designing the photomask pattern according to the OPC model. Therefore, the lithographic pattern after photolithography is close to the target pattern actually desired by the user.

[0005] However, existing optical proximity correction technologies still have many problems. Summary of the Invention

[0006] The technical problem solved by this invention is to provide an optical proximity correction method to improve correction accuracy.

[0007] To solve the above technical problems, the present invention provides an optical proximity correction method, comprising: obtaining a first correction pattern, the first correction pattern including a first correction graphic and a second correction graphic, the first correction graphic including a first correction edge, the second correction graphic including a second correction edge, the first correction edge and the second correction edge being adjacent and parallel, and having a first spacing dimension between the first correction edge and the second correction edge, the first spacing dimension being equal to the mask regularity dimension; performing a first exposure processing on the first correction pattern to obtain a first exposure pattern, the first exposure pattern including a first exposure graphic and a second exposure graphic, the first exposure graphic including a first exposure edge corresponding to the first correction edge, and the second exposure graphic including a second exposure edge corresponding to the second correction edge; and providing a target pattern, the target pattern including a first target graphic and a second target graphic, the first target graphic surrounding the first exposure graphic, the first target graphic... The first exposure pattern includes a first target edge corresponding to the first exposure edge, and the second target pattern surrounds the second exposure pattern. The second target pattern includes a second target edge corresponding to the second exposure edge. A first edge placement error between the first exposure edge and the first target edge, and a second edge placement error between the second exposure edge and the second target edge are obtained. A preset edge placement error range is provided, wherein the first edge placement error is greater than the preset edge placement error range, and the second edge placement error is within the preset edge placement error range. The first modified pattern is subjected to several optical proximity corrections, wherein the several optical proximity corrections are used to translate the first modified edge so that the first edge placement error is within the preset edge placement error range, and to translate the second modified edge to maintain the first spacing dimension greater than or equal to the mask rule dimension, and to make the second edge placement error within the preset edge placement error range.

[0008] Optionally, after obtaining the first edge placement error and finding that the first edge placement error is greater than the preset edge placement error range, the method further includes: marking the first corrected edge.

[0009] Optionally, after marking the first correction edge, the method further includes marking the second correction edge based on the first correction edge.

[0010] Optionally, the method for marking the second correction edge based on the first correction edge includes: obtaining search parameters to determine a search area based on each of the first correction edges; and marking the second correction edge when it overlaps with the search area.

[0011] Optionally, the search parameters include: an inward value M_in, an outward value M_out, a start value M_start, and an end value M_end, wherein: the inward value M_in is the distance between the first correction edge and the edge of the search region, oriented towards the direction close to the first correction shape and perpendicular to the first correction edge; the outward value M_out is the distance between the first correction edge and the edge of the search region, oriented towards the direction away from the first correction shape and perpendicular to the first correction edge; the start value M_start is the distance between the first endpoint of the first correction edge and the edge of the search region, oriented towards the direction away from the first correction shape and parallel to the first correction edge; and the end value M_end is the distance between the second endpoint of the first correction edge and the edge of the search region, oriented towards the direction away from the first correction shape and parallel to the first correction edge; wherein the first endpoint and the second endpoint are two opposite endpoints of the first correction edge.

[0012] Optionally, the inward value M_in is equal to 0; the outward value M_out is equal to the mask rule size plus the outward expansion size; the start value M_start is equal to 0; and the end value M_end is equal to 0.

[0013] Optionally, the expansion dimension is 1nm to 3nm.

[0014] Optionally, each optical proximity correction method includes: translating the first correction edge toward a direction closer to the second correction pattern by a first correction dimension; and translating the second correction edge toward a direction farther from the first correction pattern by a second correction dimension.

[0015] Optionally, the first corrected size is equal to the second corrected size.

[0016] Optionally, the first corrected size is 0.1 nm to 0.2 nm; the second corrected size is 0.1 nm to 0.2 nm.

[0017] Optionally, the first corrected size is smaller than the second corrected size.

[0018] Optionally, the method for obtaining the first corrected layout includes: providing an initial layout, the initial layout including a first graphic and a second graphic, the first graphic including a first side, the second graphic including a second side, the first side and the second side being adjacent and parallel; performing initial optical proximity correction on the initial layout to obtain the first corrected layout, wherein the first corrected side corresponds to the first side and the second corrected side corresponds to the second side.

[0019] Optionally, the method for obtaining the first edge placement error includes: obtaining a first sampling point of the first exposure edge; obtaining a second sampling point of the first target edge; obtaining a second distance dimension between the first sampling point and the second sampling point, and using the second distance dimension as the first edge placement error.

[0020] Optionally, the method for obtaining the second edge placement error includes: obtaining a third sampling point of the second exposure edge; obtaining a fourth sampling point of the second target edge; obtaining a third distance dimension between the third sampling point and the fourth sampling point, and using the third distance dimension as the second edge placement error.

[0021] Compared with the prior art, the technical solution of the embodiments of the present invention has the following beneficial effects:

[0022] The optical proximity correction method provided by the present invention performs several optical proximity corrections on the first correction pattern. These corrections are used to translate the first correction edge so that the first edge placement error is within a preset edge placement error range, and to translate the second correction edge to maintain the first spacing dimension greater than or equal to the mask rule dimension, and to maintain the second edge placement error within the preset edge placement error range. By performing these optical proximity corrections, the first edge placement error is kept within the preset edge placement error range, while the first spacing dimension is maintained greater than or equal to the mask rule dimension, and the second edge placement error is kept within the preset edge placement error range. Within a tolerable range, a portion of the second edge placement error is sacrificed to overcome the limitation of the mask rule dimension, while ensuring that the first edge placement error meets design requirements, thereby effectively improving correction accuracy. Attached Figure Description

[0023] Figures 1 to 3 A schematic diagram of the process structure of an optical proximity correction method;

[0024] Figure 4 This is a flowchart of the optical proximity correction method according to an embodiment of the present invention;

[0025] Figures 5 to 11 This is a schematic diagram of the specific steps of the optical proximity correction method according to an embodiment of the present invention. Detailed Implementation

[0026] As described in the background section, existing optical proximity correction techniques still have many problems. These will be explained in detail below with reference to the accompanying drawings.

[0027] Figures 1 to 3 A schematic diagram of the process structure of an optical proximity correction method.

[0028] Please refer to Figure 1 A first corrected pattern is obtained, which includes a first corrected pattern 1001 and a second corrected pattern 1002. The first corrected pattern 1001 includes a first corrected edge 1001a, and the second corrected pattern 1002 includes a second corrected edge 1002a. The first corrected edge 1001a and the second corrected edge 1002a are adjacent and parallel. There is a first spacing dimension d1 between the first corrected edge 1001a and the second corrected edge 1002a, and the first spacing dimension d1 is equal to the mask rule dimension dr.

[0029] Please refer to Figure 2 The first exposure pattern is obtained by performing a first exposure process on the first corrected pattern. The first exposure pattern includes a first exposure pattern 1011 and a second exposure pattern 1012. The first exposure pattern 10111 includes a first exposure edge 1011a corresponding to the first corrected edge 1001a, and the second exposure pattern 1012 includes a second exposure edge 1012a corresponding to the second corrected edge 1002a.

[0030] Please refer to Figure 3 The system provides a target layout, which includes a first target graphic 1021 and a second target graphic 1022. The first target graphic 1021 surrounds the first exposure graphic 1011 and includes a first target edge 1021a corresponding to the first exposure edge 1011a. The second target graphic 1022 surrounds the second exposure graphic 1012 and includes a second target edge 1022a corresponding to the second exposure edge 1012a. The system also acquires a first edge placement error EPE1 between the first exposure edge 1011a and the first target edge 1021a, and a second edge placement error EPE2 between the second exposure edge 1012a and the second target edge 1022a. Finally, it provides a preset edge placement error range EPE. spec The first edge placement error EPE1 is greater than the preset edge placement error range EPE. spec The second edge placement error EPE2 is located within the preset edge placement error range EPE. spec Inside.

[0031] In this embodiment, since the first edge placement error EPE1 is greater than the preset edge placement error range EPE spec This results in the final graphic size not meeting design requirements. Therefore, the first correction edge 1001a needs to be translated to reduce the first edge placement error EPE1 to the preset edge placement error range EPE. specHowever, since the first target pattern 1021 surrounds the first exposure pattern 1011, the optical proximity correction to reduce the first edge placement error EPE1 involves translating the first correction edge 1001a toward the second correction pattern 1002 by a certain dimension. Furthermore, because the first distance d1 between the first correction edge 1001a and the second correction edge 1002a has already reached the mask rule size dr, it is impossible to continue translating the first correction edge 1001a toward the second correction pattern 1002.

[0032] To address the aforementioned technical problems, the present invention provides an optical proximity correction method. Through several optical proximity corrections, the method ensures that the first edge placement error is within the preset edge placement error range, while maintaining the first spacing dimension greater than or equal to the mask rule dimension. Simultaneously, the second edge placement error is within the preset edge placement error range. Within a tolerable range, a portion of the second edge placement error is sacrificed to overcome the limitation of the mask rule dimension, while ensuring that the first edge placement error meets the design requirements, thereby effectively improving the correction accuracy.

[0033] To make the above-mentioned objectives, features and beneficial effects of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0034] Figure 4 This is a flowchart of an optical proximity correction method according to an embodiment of the present invention, including:

[0035] Step S101: Obtain a first modified layout. The first modified layout includes a first modified graphic and a second modified graphic. The first modified graphic includes a first modified edge, and the second modified graphic includes a second modified edge. The first modified edge and the second modified edge are adjacent and parallel. There is a first spacing dimension between the first modified edge and the second modified edge, and the first spacing dimension is equal to the mask rule dimension.

[0036] Step S102: Perform a first exposure process on the first corrected pattern to obtain a first exposed pattern. The first exposed pattern includes a first exposed graphic and a second exposed graphic. The first exposed graphic includes a first exposed edge corresponding to the first corrected edge, and the second exposed graphic includes a second exposed edge corresponding to the second corrected edge.

[0037] Step S103: Provide a target layout, the target layout including a first target graphic and a second target graphic, the first target graphic surrounds the first exposure graphic, the first target graphic includes a first target edge corresponding to the first exposure edge, the second target graphic surrounds the second exposure graphic, the second target graphic includes a second target edge corresponding to the second exposure edge;

[0038] Step S104: Obtain the first edge placement error between the first exposure edge and the first target edge, and the second edge placement error between the second exposure edge and the second target edge;

[0039] Step S105: Provide a preset edge placement error range, wherein the first edge placement error is greater than the preset edge placement error range, and the second edge placement error is within the preset edge placement error range;

[0040] Step S106: Perform several optical proximity corrections on the first modified pattern. The several optical proximity corrections are used to translate the first modified edge so that the first edge placement error is within the preset edge placement error range, and to translate the second modified edge so that the first spacing size is greater than or equal to the mask rule size, and so that the second edge placement error is within the preset edge placement error range.

[0041] The steps of the optical proximity correction method are described in detail below with reference to the accompanying drawings.

[0042] Figures 5 to 11 This is a schematic diagram of the specific steps of the optical proximity correction method according to an embodiment of the present invention.

[0043] Obtain a first revised pattern, which includes a first revised shape and a second revised shape. The first revised shape includes a first revised edge, and the second revised shape includes a second revised edge. The first revised edge and the second revised edge are adjacent and parallel, and there is a first spacing dimension between the first revised edge and the second revised edge, which is equal to the mask rule dimension. For the specific process of obtaining the first revised pattern, please refer to [reference needed]. Figures 5 to 6 .

[0044] Please refer to Figure 5 An initial layout is provided, which includes a first graphic 2001 and a second graphic 2002. The first graphic 2001 includes a first side 2001a, and the second graphic 2002 includes a second side 2002a. The first side 2001a and the second side 2002a are adjacent and parallel.

[0045] In this embodiment, the first graphic 2001 and the second graphic 2002 in the initial layout are graphics without any optical proximity correction. Theoretically, in the absence of optical proximity effects, the first graphic 2001 is similar to the subsequently provided first target graphic, and the second graphic 2002 is similar to the subsequently provided second target graphic.

[0046] In this embodiment, the first graphic 2001 is a rectangle, and the first side 2001a is one side of the rectangle.

[0047] In this embodiment, the second graphic 2002 is a rectangle, and the second side 2002a is one side of the rectangle.

[0048] It should be noted that, in this embodiment, the first edge 2002a and the second edge 2001a being adjacent means that the first edge 2002a and the second edge 2001a have a relative projection, and there are no other edges between the segments of the first edge 2002a and the second edge 2001a that have a relative projection.

[0049] Please refer to Figure 6 An initial optical proximity correction is performed on the initial layout to obtain the first corrected layout. The first corrected layout includes a first corrected pattern 2011 and a second corrected pattern 2012. The first corrected pattern 2011 includes a first corrected edge 2011a, and the second corrected pattern 2012 includes a second corrected edge 2012a. The first corrected edge 2011a and the second corrected edge 2012a are adjacent and parallel. The first corrected edge 2011a corresponds to the first edge 2001a, and the second corrected edge 2012a corresponds to the second edge 2002a.

[0050] In this embodiment, the initial optical proximity correction is the first optical proximity correction. The initial optical proximity correction is based on the correction model to transform the first graphic 2001 and the second graphic 2002 in the initial layout, that is, to translate the first edge 2001a and the second edge 2001b by a certain size, thereby obtaining the first corrected edge 2011a and the second corrected edge 2012a.

[0051] In this embodiment, there is a first spacing dimension d1 between the first correction edge 2011a and the second correction edge 2012a, and the first spacing dimension d1 is equal to the mask rule dimension dr.

[0052] It should be noted that in this embodiment, a mask manufacturing rule check is required during the optical proximity correction process to ensure the final pattern convergence and mask fabrication accuracy. Typically, this check examines the linewidth and spacing in the optically proximity-corrected mask pattern based on a set mask rule constraint (MRC) size dr (including linewidth and spacing values). If the first spacing dimension d1 is smaller than the mask rule constraint dr, errors may easily occur or the mask fabrication process may fail.

[0053] Please refer to Figure 7 The first exposure pattern is obtained by performing a first exposure process on the first corrected pattern. The first exposure pattern includes a first exposure pattern 2021 and a second exposure pattern 2022. The first exposure pattern 2021 includes a first exposure edge 2021a corresponding to the first corrected edge 2011a, and the second exposure pattern 2022 includes a second exposure edge 2022a corresponding to the second corrected edge 2012a.

[0054] In this embodiment, the first exposure process is a simulated exposure, that is, a simulation of an actual exposure with optical proximity effect. Because the first exposure process introduces the influence parameters of optical proximity effect, the obtained first exposure pattern 2021 will have a certain distortion compared to the first pattern 2001, and the second exposure pattern 2022 will have a certain distortion compared to the second pattern 2002.

[0055] Please refer to Figure 8 A target layout is provided, the target layout including a first target graphic 2031 and a second target graphic 2032, the first target graphic 2031 surrounds the first exposure graphic 2021, the first target graphic 2031 includes a first target edge 2031a corresponding to the first exposure edge 2021a, the second target graphic 2032 surrounds the second exposure graphic 2022, the second target graphic 2032 includes a second target edge 2032a corresponding to the second exposure edge 2022a.

[0056] In this embodiment, the target pattern is a graphic obtained without the influence of optical proximity effect. The first target pattern 2031 is similar to the first pattern 2001, and the second target pattern is similar to the second pattern 2002. That is, both the first target pattern 2031 and the second target pattern are rectangles.

[0057] Please refer to Figure 9The first edge placement error EPE1 between the first exposure edge 2021a and the first target edge 2031a, and the second edge placement error EPE2 between the second exposure edge 2022a and the second target edge 2032a are obtained.

[0058] It should be noted that, in this embodiment, due to the optical proximity effect, the first exposed pattern 2021 cannot be completely identical to the first target pattern 2031. Therefore, an edge placement error (EPE) is introduced to measure the difference between the first exposed pattern 2021 and the first target pattern 2031, as well as the difference between the second exposed pattern and the second target pattern. When the edge placement error EPE is within a certain range, the difference is considered acceptable.

[0059] In this embodiment, the method for obtaining the first edge placement error EPE1 includes: obtaining a first sampling point a1 of the first exposure edge 2021a; obtaining a second sampling point a2 of the first target edge 2031a; obtaining a second spacing dimension d2 between the first sampling point a1 and the second sampling point a2, and using the second spacing dimension d2 as the first edge placement error EPE1.

[0060] In this embodiment, the method for obtaining the second edge placement error EPE1 includes: obtaining the third sampling point a3 of the second exposure edge 2022a; obtaining the fourth sampling point a4 of the second target edge 2032a; obtaining the third spacing dimension d3 between the third sampling point a3 and the fourth sampling point a4, and using the third spacing dimension d3 as the second edge placement error EPE2.

[0061] Please continue to refer to this. Figure 9 Provides a preset edge placement error range (EPE) spec The first edge placement error EPE1 is greater than the preset edge placement error range EPE. spec The second edge placement error EPE2 is located within the preset edge placement error range EPE. spec Inside.

[0062] The preset edge placement error range EPE spec That is, to determine the magnitudes of the first edge placement error EPE1 and the second edge placement error EPE2, when both the first edge placement error EPE1 and the second edge placement error EPE2 are within the preset edge placement error range EPE... spec At that time, they considered such a gap to be acceptable.

[0063] However, in this embodiment, the first edge placement error EPE1 is greater than the preset edge placement error range EPE. spec Therefore, it is necessary to continue optical proximity correction on the first corrected pattern 2011 to reduce the first edge placement error EPE1 to the preset edge placement error range EPE. spec Inside.

[0064] Please refer to Figure 10 The preset edge placement error range (EPE) is provided. spec Then, the first corrected edge 2011a is marked; and the second corrected edge 2012a is marked based on the first corrected edge 2011a.

[0065] In this embodiment, the method for marking the second correction edge 2012a based on the first correction edge 2011a includes: obtaining search parameters based on each of the first correction edges 2011a to determine the search region S; and marking the second correction edge 2012a when it overlaps with the search region S.

[0066] In this embodiment, the search parameters include: an inward value M_in, an outward value M_out, a start value M_start, and an end value M_end, wherein: the inward value M_in is the direction toward the first corrected shape 2011 and perpendicular to the first corrected edge 2011a, and the distance between the first corrected edge 2011a and the edge of the search region S; the outward value M_out is the direction toward the direction away from the first corrected shape 2011 and perpendicular to the first corrected edge 2011a, and the distance between the first corrected edge 2011a and the edge of the search region S; The start value M_start is the distance between the first endpoint O1 of the first correction edge 2011a and the edge of the search region S, oriented in a direction away from the first correction pattern 2011 and parallel to the first correction edge 2011a; the end value M_end is the distance between the second endpoint O2 of the first correction edge 2011a and the edge of the search region S, oriented in a direction away from the first correction pattern 2011 and parallel to the first correction edge 2011a; wherein, the first endpoint O1 and the second endpoint O2 are two opposite endpoints of the first correction edge 2011a.

[0067] In this embodiment, the inward value M_in is equal to 0; the outward value M_out is equal to the mask rule size dr plus the outward expansion size de; the start value M_start is equal to 0; and the end value M_end is equal to 0.

[0068] In this embodiment, the outer expansion size de is 1nm to 3nm. When the outer expansion size de is greater than 3nm, the formed search area S is prone to selecting the edges of other shapes. In subsequent optical proximity correction, the edges of the additionally selected shapes are also translated, which can easily cause additional problems.

[0069] Please refer to Figure 11 The first corrected pattern is subjected to several optical proximity corrections, which are used to translate the first corrected edge 2011a so that the first edge placement error EPE1 is within the preset edge placement error range EPE. spec The second correction edge 2012a is translated to maintain the first spacing dimension d1 greater than or equal to the mask rule dimension dr, and to make the second edge placement error EPE2 within the preset edge placement error range EPE. spec Inside.

[0070] In this embodiment, through several optical proximity corrections, the first edge placement error EPE1 is made to fall within the preset edge placement error range EPE. spec Within this range, the first spacing dimension d1 is maintained to be greater than or equal to the mask regularity dimension dr, while the second edge placement error EPE2 is within the preset edge placement error range EPE. spec Within a tolerable range, a portion of the second edge placement error EPE2 is sacrificed to overcome the limitation of the mask rule size dr, while ensuring that the first edge placement error EPE1 meets the design requirements, thereby effectively improving the correction accuracy.

[0071] In this embodiment, each optical proximity correction method includes: translating the first correction edge 2011a toward the direction closer to the second correction pattern 2012 by a first correction dimension c1; and translating the second correction edge 2012a toward the direction away from the first correction pattern 2011 by a second correction dimension c2.

[0072] In this embodiment, to ensure that the first spacing dimension d1 is not less than the mask rule dimension dr, the first correction dimension c1 is equal to the second correction dimension c2. In other embodiments, the first correction dimension may be smaller than the second correction dimension.

[0073] In this embodiment, the first correction size c1 is 0.1 nm to 0.2 nm; the second correction size c2 is 0.1 nm to 0.2 nm. When the first correction size c1 and the second correction size c2 are less than 0.1 nm, the number of optical proximity corrections increases, thus affecting the correction efficiency; when the first correction size c1 and the second correction size c2 are greater than 0.2 nm, the size of each translation is large, resulting in greater disturbance and making it impossible to find the optimal correction size.

[0074] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. An optical proximity correction method characterized by, include: Obtain a first modified layout, which includes a first modified graphic and a second modified graphic. The first modified graphic includes a first modified edge, and the second modified graphic includes a second modified edge. The first modified edge and the second modified edge are adjacent and parallel. There is a first spacing dimension between the first modified edge and the second modified edge, and the first spacing dimension is equal to the mask rule dimension. The first exposure pattern is obtained by performing a first exposure process on the first corrected pattern. The first exposure pattern includes a first exposure graphic and a second exposure graphic. The first exposure graphic includes a first exposure edge corresponding to the first corrected edge, and the second exposure graphic includes a second exposure edge corresponding to the second corrected edge. A target layout is provided, the target layout including a first target graphic and a second target graphic, the first target graphic surrounding a first exposure graphic, the first target graphic including a first target edge corresponding to the first exposure edge, the second target graphic surrounding a second exposure graphic, the second target graphic including a second target edge corresponding to the second exposure edge; Obtain the first edge placement error between the first exposure edge and the first target edge, and the second edge placement error between the second exposure edge and the second target edge; A preset edge placement error range is provided, wherein the first edge placement error is greater than the preset edge placement error range, and the second edge placement error is within the preset edge placement error range; the first corrected pattern is subjected to several optical proximity corrections, wherein the several optical proximity corrections are used to translate the first corrected edge so that the first edge placement error is within the preset edge placement error range, and to translate the second corrected edge so that the first spacing dimension is greater than or equal to the mask rule dimension, and the second edge placement error is within the preset edge placement error range.

2. The optical proximity correction method of claim 1, wherein, After obtaining the first edge placement error, and finding that the first edge placement error is greater than the preset edge placement error range, the method further includes: marking the first corrected edge.

3. The optical proximity correction method of claim 2, wherein, After marking the first correction edge, the method further includes marking the second correction edge based on the first correction edge.

4. The optical proximity correction method of claim 3, wherein, The method for marking the second correction edge based on the first correction edge includes: obtaining search parameters to determine a search area based on each of the first correction edges; and marking the second correction edge when it overlaps with the search area.

5. The optical proximity correction method of claim 4, wherein, The search parameters include: inward value M_in, outward value M_out, start value M_start, and end value M_end, where: The inward value M_in is the direction toward the first corrected shape and perpendicular to the first corrected edge, and the distance between the first corrected edge and the edge of the search region; The outward value M_out is the direction that is away from the first corrected shape and perpendicular to the first corrected edge, and the distance between the first corrected edge and the edge of the search region; The starting value M_start is the direction that is away from the first corrected shape and parallel to the first corrected edge, and the distance between the first endpoint of the first corrected edge and the edge of the search area; The end value M_end is the distance between the second endpoint of the first correction edge and the edge of the search region, which is oriented away from the first correction pattern and parallel to the first correction edge. Wherein, the first endpoint and the second endpoint are the two opposite endpoints of the first correction edge.

6. The optical proximity correction method as described in claim 5, characterized in that, The inward value M_in is equal to 0; the outward value M_out is equal to the mask rule size plus the outward expansion size; the start value M_start is equal to 0; and the end value M_end is equal to 0.

7. The optical proximity correction method as described in claim 6, characterized in that, The external expansion dimension is 1nm to 3nm.

8. The optical proximity correction method as described in claim 1, characterized in that, Each optical proximity correction method includes: translating the first correction edge toward a direction closer to the second correction pattern by a first correction dimension; and translating the second correction edge toward a direction farther from the first correction pattern by a second correction dimension.

9. The optical proximity correction method as described in claim 8, characterized in that, The first corrected dimension is equal to the second corrected dimension.

10. The optical proximity correction method as described in claim 9, characterized in that, The first corrected size is 0.1nm to 0.2nm; the second corrected size is 0.1nm to 0.2nm.

11. The optical proximity correction method as described in claim 8, characterized in that, The first correction dimension is smaller than the second correction dimension.

12. The optical proximity correction method as described in claim 1, characterized in that, The method for obtaining the first corrected layout includes: providing an initial layout, the initial layout including a first graphic and a second graphic, the first graphic including a first side, the second graphic including a second side, the first side and the second side being adjacent and parallel; performing initial optical proximity correction on the initial layout to obtain the first corrected layout, wherein the first corrected side corresponds to the first side and the second corrected side corresponds to the second side.

13. The optical proximity correction method as described in claim 1, characterized in that, The method for obtaining the first edge placement error includes: obtaining a first sampling point of the first exposure edge; obtaining a second sampling point of the first target edge; obtaining a second distance dimension between the first sampling point and the second sampling point, and using the second distance dimension as the first edge placement error.

14. The optical proximity correction method as described in claim 1, characterized in that, The method for obtaining the second edge placement error includes: obtaining a third sampling point of the second exposure edge; obtaining a fourth sampling point of the second target edge; obtaining a third distance dimension between the third sampling point and the fourth sampling point, and using the third distance dimension as the second edge placement error.

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