Optical Proximity Correction Method

Abstract

An optical proximity correction method includes: providing a substrate having a plurality of defective patterns thereon; providing an initial layout; obtaining overlapping areas of the initial patterns and the defective patterns; removing the overlapping areas from the initial layout to obtain a first layout; obtaining a second layout based on the overlapping areas; performing a plurality of first optical proximity corrections on the first layout to obtain an initial first optical proximity correction layout; obtaining a first light intensity distribution based on the initial first optical proximity correction; obtaining a second light intensity distribution based on the second layout; processing the first light intensity distribution and the second light intensity distribution to obtain a third light intensity distribution; and obtaining a first exposure image based on the third light intensity distribution. Obtaining the second layout by obtaining the overlapping areas fully accounts for the optical scattering effects generated by the defective patterns in the substrate during the optical proximity correction process, thereby avoiding positional or topographical adjustments to the initial patterns in the initial layout and effectively expanding the scope of application of the optical proximity correction.

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] Photolithography is a crucial technology in semiconductor manufacturing, enabling the transfer of patterns from a mask onto the surface of a silicon wafer, creating semiconductor products that meet design requirements. The photolithography process begins with an exposure step, where light passes through the translucent or reflective areas of the mask onto a photoresist-coated silicon wafer, reacting photochemically with the photoresist. Next, a development step utilizes the solubility of the developer in the photosensitive and unsensitive photoresists to form a photoresist pattern, enabling the transfer of the mask pattern. Finally, an etching step involves etching the silicon wafer based on the photoresist pattern, further transferring the mask pattern to the wafer.

[0003] However, during the mask manufacturing process, various unpredictable factors, such as the environment, substrate texture, photoresist, etc., may cause defects in the manufactured mask, thereby reducing the accuracy of the formed photolithographic pattern. Summary of the Invention

[0004] The technical problem solved by the present invention is to provide an optical proximity correction method, which can effectively improve the accuracy of photolithography patterns.

[0005] To solve the above problems, the present invention provides an optical proximity correction method, comprising: providing a substrate having a plurality of defective patterns thereon; providing an initial layout, the initial layout including a plurality of initial patterns; overlapping and comparing the initial layout with the substrate to obtain an overlapping area between the initial patterns and the defective patterns; removing the overlapping area in the initial layout to obtain a first layout, the first layout including a plurality of first patterns corresponding to the initial patterns; obtaining a second layout based on the overlapping area, the second layout including a plurality of second patterns, the second patterns having the same position and shape as the overlapping area; performing a first optical proximity correction on the first layout several times to obtain an initial first optical proximity correction layout; exposing the initial first optical proximity correction layout to obtain a first light intensity distribution; exposing the second layout to obtain a second light intensity distribution; superimposing the first light intensity distribution and the second light intensity distribution to obtain a third light intensity distribution; and obtaining a first exposure image based on the third light intensity distribution, the first exposure image including a plurality of first exposure patterns.

[0006] Optionally, the method for obtaining the second layout based on the overlapping area includes: obtaining position information and shape information of the overlapping area; and forming the second layout based on the position information and shape information of the overlapping area.

[0007] Optionally, the method for obtaining the position information of the overlapping area includes: establishing a coordinate system in the plane where the substrate is located; obtaining the coordinates of the center point of the overlapping area in the coordinate system, and using the coordinates as the position information of the overlapping area.

[0008] Optionally, the method for obtaining the first exposure image according to the third light intensity distribution includes: providing a photoresist layer; reacting the third light intensity distribution with the photoresist layer to form a photoacid distribution in the photoresist layer; and developing the photoacid distribution in the photoresist layer to form the first exposure image.

[0009] Optionally, the function equation of the first light intensity distribution is:

[0010]

[0011] The function equation of the second light intensity distribution is:

[0012]

[0013] in, is the Fourier transform of the TCC function, which is determined by the light source function and the pupil function; is the Fourier transform of the functional equation of the initial first optical proximity correction map; is the Fourier transform of the function equation in the second version, where f and g are the independent variables in the frequency domain function.

[0014] Optionally, the first light intensity distribution and the second light intensity distribution are superimposed to obtain a function equation of a third light intensity distribution:

[0015]

[0016] in,

[0017] Wherein, PSF1 is the point spread function associated with the initial first optical proximity correction layout; PSF2 is the point spread function associated with the second layout.

[0018] Optionally, the method for obtaining the initial layout includes: providing a target layout, the target layout including a plurality of target graphics corresponding to the first exposure graphics, the target graphics being surrounded by multiple edges; and amplifying each target graphic in the target layout to obtain the initial layout.

[0019] Optionally, the method of enlarging each target graphic includes: enlarging each side of the target graphic by the same multiple.

[0020] Optionally, after acquiring the first exposure image, the method further includes: determining whether the first exposure image meets correction settings.

[0021] Optionally, the method for determining whether the first exposure image satisfies the correction setting includes: setting a plurality of first sampling points in each of the first exposure patterns; setting a plurality of second sampling points on the target pattern corresponding to the first exposure pattern; overlapping and comparing the corresponding first exposure pattern with the target pattern, obtaining a spacing size between the first sampling points and the second sampling points, and using the spacing size as an edge position error of the first exposure pattern; providing an error threshold, and comparing the edge position error with the error threshold.

[0022] Optionally, when the edge position error is less than or equal to the error threshold, the optical proximity correction is completed, the overlapping area is filled into the initial first optical proximity correction layout to form a first optical proximity correction layout, and the first optical proximity correction layout is used as the final correction layout.

[0023] Optionally, when the edge position error is greater than the error threshold, the initial first optical proximity correction is performed several times on the initial first optical proximity correction layout to obtain an initial second optical proximity correction layout; the steps of obtaining the first light intensity distribution to determining whether the first exposure image meets the correction setting are re-executed on the initial second optical proximity correction layout until the edge position error is less than or equal to the error threshold, and the optical proximity correction is completed; the overlapping area is filled into the initial second optical proximity correction layout to form a second optical proximity correction layout, and the second optical proximity correction layout is used as the final correction layout.

[0024] Optionally, before performing several first optical proximity corrections on the first layout, the method further includes: exposing the first layout to obtain a first light intensity distribution; exposing the second layout to obtain a second light intensity distribution; superimposing the first light intensity distribution and the second light intensity distribution to obtain a third light intensity distribution; obtaining a first exposure image based on the third light intensity distribution, the first exposure image including several first exposure patterns; and determining whether the first exposure image meets the correction settings.

[0025] Optionally, if the first exposure image meets the correction setting, the initial layout is used as the final corrected layout.

[0026] Optionally, if the first exposure image does not meet the correction setting, the first optical proximity correction is performed on the first layout several times to obtain an initial first optical proximity correction layout.

[0027] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0028] In the method for forming the technical solution of the present invention, a second layout is obtained through the overlapping region, fully accounting for the optical scattering effects of the defective patterns in the substrate during the optical proximity correction process. Furthermore, the first optical proximity correction is performed only on the first layout, eliminating the interference of optical scattering caused by the defective patterns in the substrate from the optical proximity correction process. This avoids adjusting the position or topography of the initial patterns in the initial layout, ensuring that layout corrections are not limited by the number of defective patterns or the minimum feature size specified in layout design rules, effectively expanding the scope of optical proximity correction. Furthermore, during the optical proximity correction process, the second layout remains unchanged, while only the first layout is corrected. This allows for rapid identification of the correction direction for reducing edge position errors, thereby improving the efficiency of optical proximity correction. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural diagram of a semiconductor structure;

[0030] Figure 2 and Figure 3 It is a structural diagram of another semiconductor structure;

[0031] Figure 4 and Figure 5 It is a structural diagram of another semiconductor structure;

[0032] Figure 6 This is a flow chart of the optical proximity correction method according to an embodiment of the present invention.

[0033] Figures 7 to 21 1 is a schematic structural diagram of each step of an embodiment of an optical proximity correction method of the present invention. DETAILED DESCRIPTION

[0034] As described in the background art, defects in the mask may reduce the accuracy of the formed photolithographic pattern, which will be described in detail below with reference to the accompanying drawings.

[0035] Please refer to Figure 1 , providing a substrate 100 having a plurality of defects 101 thereon; forming a light shielding layer 102 on the substrate 100, wherein the light shielding layer 102 has openings 103 therein, and part of the openings 103 exposes the defects 101.

[0036] Extreme ultraviolet lithography (also known as EUV or EUVL) is a lithography technology that uses extreme ultraviolet (EUV) wavelengths, which are 13.5nm. Almost all optical materials have strong absorption of 13.5nm wavelength extreme ultraviolet light. Therefore, the optical system of the EUV lithography machine can only use mirrors.

[0037] In this embodiment, extreme ultraviolet lithography is used. The substrate 100 acts as a reflector, and the pattern formed by the openings 103 in the light-shielding layer 102 is consistent with the pattern in the mask. When the surface of the substrate 100 is sufficiently smooth, the reflection angle of the extreme ultraviolet light after reflection from the surface of the substrate 100 is the same as the incident angle. However, in this embodiment, due to the presence of defects 101 on the surface of the substrate 100, when the openings expose the defects 101, the extreme ultraviolet light will be diffusely reflected from the surface of the substrate 100. Due to the presence of diffuse reflection, the reflected light will be inconsistent with the incident light, thereby reducing the accuracy of the final lithographic pattern.

[0038] In order to solve the above problems, two solutions are usually adopted in the prior art.

[0039] Please refer to Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of the opening position before adjustment. Figure 3 Schematic diagram of the adjusted opening position. One method is to adjust the position of the opening 103 so that the light shielding layer 102 completely covers all defects 101 as much as possible. This method is very effective when there are few defects 101, but when there are many defects 101, some defects 101 may still not be covered by the light shielding layer 102.

[0040] Please refer to Figure 4 and Figure 5 , Figure 4 This is a schematic diagram of the opening shape before adjustment. Figure 5 Schematic diagram of the adjusted opening morphology. Another method is to adjust the morphology of the opening 103 to prevent the opening 103 from exposing the defect 101. However, this adjustment is limited by the minimum feature size of the opening 103. Therefore, in some cases, there may still be defects 101 that cannot be covered by the light shielding layer 102.

[0041] On this basis, the present invention provides an optical proximity correction method. By acquiring a second layout through the overlapping region, the optical scattering effects generated by the defective patterns in the substrate are fully considered during the optical proximity correction process. Furthermore, the first optical proximity correction is performed only on the first layout, eliminating the interference of optical scattering generated by the defective patterns in the substrate from the optical proximity correction process. This avoids adjusting the position or topography of the initial patterns in the initial layout, ensuring that layout correction is not limited by the number of defective patterns or the minimum feature size in the layout design rules, effectively expanding the scope of optical proximity correction. Furthermore, during the optical proximity correction process, the second layout remains unchanged, while only the first layout is corrected. This allows for rapid identification of the correction direction for reducing edge position errors, thereby improving the efficiency of optical proximity correction.

[0042] In order to make the above-mentioned objects, features and advantages 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.

[0043] Figure 6 : is a flow chart of an optical proximity correction method according to an embodiment of the present invention, comprising:

[0044] Step S01, providing a substrate, wherein the substrate has a plurality of defect patterns;

[0045] Step S02, providing an initial layout, wherein the initial layout includes a plurality of initial graphics;

[0046] Step S03, overlapping and comparing the initial pattern with the substrate to obtain an overlapping area between the initial pattern and the defect pattern;

[0047] Step S04, removing the overlapping area from the initial layout to obtain a first layout, wherein the first layout includes a plurality of first graphics corresponding to the initial graphics;

[0048] Step S05, obtaining a second layout according to the overlapping area, wherein the second layout includes a plurality of second graphics, and the second graphics have the same position and shape as the overlapping area;

[0049] Step S06, performing a plurality of first optical proximity corrections on the first layout to obtain an initial first optical proximity correction layout;

[0050] Step S07, performing exposure processing on the initial first optical proximity correction pattern to obtain a first light intensity distribution;

[0051] Step S08, performing exposure processing on the second layout to obtain a second light intensity distribution;

[0052] Step S09, superimposing the first light intensity distribution and the second light intensity distribution to obtain a third light intensity distribution;

[0053] Step S10: acquiring a first exposure image according to the third light intensity distribution, wherein the first exposure image includes a plurality of first exposure patterns.

[0054] The steps of the optical proximity correction method will be described in detail below with reference to the accompanying drawings.

[0055] Figures 7 to 21 1 is a schematic structural diagram of each step of the optical proximity correction method according to an embodiment of the present invention.

[0056] Please refer to Figure 7 , providing a substrate 200 having a plurality of defect patterns 201 thereon.

[0057] In this embodiment, extreme ultraviolet lithography technology is used to achieve patterned transfer. Since the wavelength of extreme ultraviolet light is 13.5nm, almost all optical materials have strong absorption of extreme ultraviolet light with a wavelength of 13.5nm. Therefore, the optical system of the EUV lithography machine only uses mirrors.

[0058] Therefore, in this embodiment, the substrate 200 is equivalent to a reflector, and its function is to reflect the incident EUV light, thereby realizing the light path transfer in EUV lithography.

[0059] Ideally, the surface of substrate 200 is perfectly smooth, meaning the incident and reflection angles of the EUV light are symmetrical about a line perpendicular to the surface of substrate 200. However, in actual production, the surface of substrate 200 may contain numerous uneven defect patterns 201. These defect patterns 201 can cause diffuse reflection of the EUV light, reducing the accuracy of the final photolithographic pattern.

[0060] Provide an initial layout, which includes several initial graphics. Please refer to the specific process of obtaining the initial layout. Figures 8 and 9 .

[0061] Please refer to Figure 8 , providing a target layout 300, wherein the target layout 300 includes a plurality of target graphics 301, and the target graphics 301 are surrounded by multiple edges.

[0062] In this embodiment, the target pattern 301 is a target for optical proximity correction, that is, in an ideal state, a pattern subsequently formed on the wafer is consistent with the target pattern 301 .

[0063] Please refer to Figure 9, each target graphic 301 in the target layout 300 is magnified to obtain the initial layout 400 , wherein the initial layout 400 has a plurality of initial graphics 401 corresponding to the target graphics 301 .

[0064] In this embodiment, the method of magnifying each target graphic 301 includes: magnifying each side of the target graphic 301 by the same multiple.

[0065] It should be noted that, in this embodiment, the initial layout 400 is the first iteration of the optical proximity correction of the target layout 300, and the convergence speed of the optical proximity correction is improved by enlarging the target layout 300. In other embodiments, the initial layout can also be Figure 1 The present invention is not limited thereto.

[0066] Please refer to Figure 10 , the initial layout 400 is overlapped and compared with the substrate 200 to obtain the overlapping area 202 of the initial pattern 401 and the defect pattern 201.

[0067] In this embodiment, the overlapping area 202 refers to the defective pattern 201 that cannot be covered by the initial layout 400 . These exposed defective patterns 201 will cause subsequent diffuse reflection of extreme ultraviolet light.

[0068] Please refer to Figure 11 , removing the overlapping area 202 from the initial layout 400 to obtain a first layout 500 , wherein the first layout 500 includes a plurality of first graphics 501 corresponding to the initial graphics 401 .

[0069] In this embodiment, by removing the overlapping region 202 from the initial layout 400 to form the first layout 500, the first layout 500 completely avoids the diffuse reflection effect caused by the defective pattern 201. In the subsequent optical proximity correction process, only the first layout 500 is subjected to the first optical proximity correction, eliminating the interference of optical scattering caused by the defective pattern 201 in the substrate 200 from the optical proximity correction process. This allows for the rapid identification of the correction direction for reducing the edge position error, thereby improving the efficiency of the optical proximity correction.

[0070] The second layout is obtained based on the overlapping area 202. The second layout includes a plurality of second graphics, and the second graphics have the same position and shape as the overlapping area 202. The formation process of the second layout can be referred to Figures 12 to 13 .

[0071] Please refer to Figure 12, obtain the position information and shape information of the overlapping area 202.

[0072] In this embodiment, the method for obtaining the position information of the overlapping area 202 includes: establishing a coordinate system in the plane where the substrate 200 is located; obtaining the coordinates of the center point of the overlapping area 202 in the coordinate system, and using the coordinates as the position information of the overlapping area 202.

[0073] Please refer to Figure 13 The second layout 600 is formed according to the position information and shape information of the overlapping area 202 . The second layout 600 includes a plurality of second graphics 601 . The second graphics 601 have the same position and shape as the overlapping area 202 .

[0074] In this embodiment, the second layout 600 is obtained through the overlapping area 202, and the optical scattering effects generated by the defective pattern 201 in the substrate 200 are fully taken into account in the process of optical proximity correction, thereby avoiding the adjustment of the position or morphology of the initial pattern 401 in the initial layout 400. Therefore, the correction of the layout is not limited by the number of the defective patterns 201 and the minimum feature size in the layout design rules, effectively increasing the scope of application of optical proximity correction.

[0075] Please refer to Figure 14 , performing several first optical proximity corrections on the first layout 500 to obtain an initial first optical proximity correction layout 700 .

[0076] In this embodiment, by performing the first optical proximity correction only on the first pattern 500, the optical scattering caused by the defective pattern 201 in the substrate 200 is excluded from the optical proximity correction process, and the correction direction for reducing the edge position error can be quickly determined, thereby improving the efficiency of the optical proximity correction.

[0077] Please refer to Figure 15 , performing exposure processing on the initial first optical proximity correction plate 700 to obtain a first light intensity distribution.

[0078] In this embodiment, the function equation of the first light intensity distribution is:

[0079]

[0080] in, is the Fourier transform of the TCC function, which is determined by the light source function and the pupil function; is the Fourier transform of the function equation of the initial first optical proximity correction diagram 700, where f and g are independent variables in the frequency domain function.

[0081] Please refer to Figure 16 , performing exposure processing on the second layout 600 to obtain a second light intensity distribution.

[0082] In this embodiment, the function equation of the second light intensity distribution is:

[0083]

[0084] in, is the Fourier transform of the function equation of the second version 600, where f and g are independent variables in the frequency domain function.

[0085] In this embodiment, after obtaining the first light intensity distribution and the second light intensity distribution, the first light intensity distribution and the second light intensity distribution are superimposed to obtain a third light intensity distribution, and a function equation of the third light intensity distribution is obtained:

[0086]

[0087] in,

[0088] PSF1 is the point spread function associated with the initial first optical proximity correction map 700 ; PSF2 is the point spread function associated with the second map 600 .

[0089] Please refer to Figure 17 , a first exposure image 800 is acquired according to the third light intensity distribution, where the first exposure image 800 includes a plurality of first exposure patterns 801 .

[0090] In this embodiment, the method for obtaining the first exposure image 800 according to the third light intensity distribution includes: providing a photoresist layer (not shown); reacting the third light intensity distribution with the photoresist layer to form a photoacid distribution in the photoresist layer; and developing the photoacid distribution in the photoresist layer to form the first exposure image 800.

[0091] After obtaining the first exposure image 800, the method further includes: determining whether the first exposure image 800 satisfies the correction setting. For the specific determination process, please refer to Figures 18 to 20 .

[0092] Please refer to Figure 18 , a number of first sampling points a are set in each of the first exposure patterns 801.

[0093] Please refer to Figure 19 , a plurality of second sampling points b are set on the target pattern 301 corresponding to the first exposure pattern 801.

[0094] Please refer to Figure 20, overlapping and comparing the corresponding first exposure pattern 801 with the target pattern 301, obtaining a spacing dimension d1 between the first sampling point a and the second sampling point b, and using the spacing dimension d1 as an edge position error of the first exposure pattern 801; providing an error threshold, and comparing the edge position error with the error threshold.

[0095] In this embodiment, please refer to Figure 21 , the edge position error is less than the error threshold, the optical proximity correction is completed, the overlapping area 202 is filled into the initial first optical proximity correction layout 700 to form a first optical proximity correction layout 900, and the first optical proximity correction layout 900 is used as the final correction layout.

[0096] In other embodiments, when the edge position error is greater than the error threshold, the initial first optical proximity correction pattern is subjected to several second optical proximity corrections to obtain an initial second optical proximity correction pattern; the steps of obtaining the first light intensity distribution to determining whether the first exposure image satisfies the correction setting are re-executed on the initial second optical proximity correction pattern until the edge position error is less than or equal to the error threshold, and the optical proximity correction is completed. For the specific process, please refer to Figures 14 to 20 , and related instructions, will not be repeated here.

[0097] At this point, the optical proximity correction of the initial layout 400 is complete. A second layout 600 is obtained through the overlap region 202. The optical scattering effects of the defective pattern 201 in the substrate 200 are fully considered during the optical proximity correction process. Furthermore, the first optical proximity correction is performed only on the first layout 500, eliminating the interference of optical scattering caused by the defective pattern 201 in the substrate from the optical proximity correction process. This avoids adjusting the position or topography of the initial pattern 401 in the initial layout 400. This ensures that layout correction is not limited by the number of defective patterns 201 or the minimum feature size specified in the layout design rules, effectively expanding the applicability of optical proximity correction. Furthermore, during the optical proximity correction process, the second layout 600 remains unchanged, while only the first layout 500 is corrected. This allows for a quick and clear correction direction to reduce edge position errors, thereby improving the efficiency of optical proximity correction.

[0098] It should be noted that, in this embodiment, before performing several first optical proximity corrections on the first plate 500, the following steps are further included: exposing the first plate 500 to obtain a first light intensity distribution; exposing the second plate 600 to obtain a second light intensity distribution; superimposing the first light intensity distribution and the second light intensity distribution to obtain a third light intensity distribution; obtaining a first exposure image 800 based on the third light intensity distribution, wherein the first exposure image 800 includes several first exposure patterns 801; and determining whether the first exposure image 800 meets the correction setting. For the specific process, please refer to Figures 15 to 20 , I will not go into details here.

[0099] If the first exposure image 800 satisfies the correction setting, the initial layout 400 is used as the final corrected layout.

[0100] If the first exposure image 800 does not meet the correction setting, the first optical proximity correction is performed several times on the first plate 500 to obtain the initial first optical proximity correction plate 700 .

[0101] 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 a substrate having a plurality of defect patterns thereon; Providing an initial layout, wherein the initial layout includes a plurality of initial graphics; Overlapping and comparing the initial pattern with the substrate to obtain an overlapping area between the initial pattern and the defect pattern; Removing the overlapping area from the initial layout to obtain a first layout, wherein the first layout includes a plurality of first graphics corresponding to the initial graphics; Acquire a second layout according to the overlapping area, wherein the second layout includes a plurality of second graphics, and the second graphics have the same position and shape as the overlapping area; Performing a plurality of first optical proximity corrections on the first layout to obtain an initial first optical proximity correction layout; performing exposure processing on the initial first optical proximity correction pattern to obtain a first light intensity distribution; performing exposure processing on the second layout to obtain a second light intensity distribution; superimposing the first light intensity distribution and the second light intensity distribution to obtain a third light intensity distribution; A first exposure image is acquired according to the third light intensity distribution, where the first exposure image includes a plurality of first exposure patterns.

2. The optical proximity correction method according to claim 1, wherein: The method for obtaining the second layout according to the overlapping area includes: obtaining position information and shape information of the overlapping area; and forming the second layout according to the position information and shape information of the overlapping area.

3. The optical proximity correction method according to claim 2, wherein: The method for obtaining the position information of the overlapping area includes: establishing a coordinate system in the plane where the substrate is located; obtaining the coordinates of the center point of the overlapping area in the coordinate system, and using the coordinates as the position information of the overlapping area.

4. The optical proximity correction method according to claim 1, wherein: The method for obtaining a first exposure image according to the third light intensity distribution includes: providing a photoresist layer; reacting the third light intensity distribution with the photoresist layer to form a photoacid distribution in the photoresist layer; and developing the photoacid distribution in the photoresist layer to form the first exposure image.

5. The optical proximity correction method according to claim 1, wherein: The function equation of the first light intensity distribution is: The function equation of the second light intensity distribution is: in, is the Fourier transform of the TCC function, which is determined by the light source function and the pupil function; is the Fourier transform of the functional equation of the initial first optical proximity correction map; is the Fourier transform of the function equation in the second version, where f and g are the independent variables in the frequency domain function.

6. The optical proximity correction method according to claim 5, wherein: The first light intensity distribution and the second light intensity distribution are superimposed to obtain a function equation of a third light intensity distribution: in, Wherein, PSF1 is the point spread function associated with the initial first optical proximity correction layout; PSF2 is the point spread function associated with the second layout.

7. The optical proximity correction method according to claim 1, wherein: The method for obtaining the initial layout includes: providing a target layout, wherein the target layout includes a plurality of target patterns corresponding to the first exposure patterns, and the target patterns are surrounded by multiple edges; and amplifying each target pattern in the target layout to obtain the initial layout.

8. The optical proximity correction method according to claim 7, wherein: The method for magnifying each target graphic includes: magnifying each side of the target graphic by the same multiple.

9. The optical proximity correction method according to claim 7, wherein: After acquiring the first exposure image, the method further includes: determining whether the first exposure image satisfies a correction setting.

10. The optical proximity correction method according to claim 9, wherein: The method for determining whether the first exposure image satisfies correction settings includes: setting a plurality of first sampling points in each of the first exposure patterns; setting a plurality of second sampling points on the target pattern corresponding to the first exposure pattern; overlapping and comparing the corresponding first exposure patterns with the target pattern, obtaining a spacing between the first sampling points and the second sampling points, and using the spacing as an edge position error of the first exposure pattern; providing an error threshold, and comparing the edge position error with the error threshold.

11. The optical proximity correction method according to claim 10, wherein: When the edge position error is less than or equal to the error threshold, the optical proximity correction is completed, the overlapping area is filled into the initial first optical proximity correction layout to form a first optical proximity correction layout, and the first optical proximity correction layout is used as the final correction layout.

12. The optical proximity correction method according to claim 10, wherein: When the edge position error is greater than the error threshold, performing a plurality of second optical proximity corrections on the initial first optical proximity correction layout to obtain an initial second optical proximity correction layout; re-performing the steps of obtaining the first light intensity distribution to determining whether the first exposure image satisfies the correction setting on the initial second optical proximity correction layout until the edge position error is less than or equal to the error threshold, and the optical proximity correction is completed; filling the overlapping area into the initial second optical proximity correction layout to form a second optical proximity correction layout, and using the second optical proximity correction layout as the final correction layout.

13. The optical proximity correction method according to claim 1, wherein: Before performing several first optical proximity corrections on the first layout, the method also includes: exposing the first layout to obtain a first light intensity distribution; exposing the second layout to obtain a second light intensity distribution; superimposing the first light intensity distribution and the second light intensity distribution to obtain a third light intensity distribution; obtaining a first exposure image based on the third light intensity distribution, the first exposure image including several first exposure patterns; and determining whether the first exposure image meets the correction settings.

14. The optical proximity correction method according to claim 13, wherein: If the first exposure image satisfies the correction setting, the initial layout is used as the final corrected layout.

15. The optical proximity correction method according to claim 13, wherein: If the first exposure image does not meet the correction setting, the first optical proximity correction is performed on the first layout several times to obtain an initial first optical proximity correction layout.

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