Photomasks, methods for generating photomask patterns, semiconductor structures and their fabrication methods

Abstract

This application provides a photomask, a method for generating a photomask pattern, a semiconductor structure, and a method for fabricating the same. The photomask has a plurality of preset exposure areas spaced apart along a first direction; a first light-shielding area is disposed between adjacent preset exposure areas; the preset exposure areas or the first light-shielding area have a width in a first direction and a length extending along a second direction; the length is greater than the width; wherein, the preset exposure areas include a plurality of target exposure areas spaced apart along the second direction; a second light-shielding area is disposed between adjacent target exposure areas; the size of the second light-shielding area is smaller than the minimum feature size of the photomask. By spaced apart multiple sub-resolution second light-shielding areas along the length extension direction of the preset exposure areas of the photomask, the bottom of the photoresist pattern structure obtained after exposure is wider at the position corresponding to the second light-shielding area, thereby improving the stability of the photoresist pattern structure and improving the inverted line problem.

Description

Technical Field

[0001] The embodiments in this application relate to the field of semiconductor process technology, and in particular to a photomask, a method for generating a photomask pattern, a semiconductor structure, and a method for preparing the same. Background Technology

[0002] In semiconductor fabrication, photolithography can be used to transfer patterns from a photomask or mask onto a photoresist coated on a substrate surface, forming a patterned photoresist layer to facilitate subsequent etching, deposition, and other processes.

[0003] However, as the process nodes continue to shrink, the problem of inverted lines in the patterned photoresist layer formed by the photolithography process becomes more and more serious. It is prone to collapse and deformation, which reduces the accuracy of pattern transfer and affects product yield. Summary of the Invention

[0004] In view of this, several embodiments of this application aim to provide a photomask, a method for generating a photomask pattern, a semiconductor structure, and a method for preparing the same, which can improve the problem of inverted lines in the patterned photoresist layer formed by the photolithography process.

[0005] One embodiment of this application provides a photomask having a plurality of preset exposure areas spaced apart along a first direction; a first light-shielding area is disposed between adjacent preset exposure areas; the preset exposure areas or the first light-shielding area have a width in a first direction and a length extending along a second direction; the length is greater than the width; wherein, the first direction is the arrangement direction of the preset exposure areas or the first light-shielding area; the second direction is a direction perpendicular to the first direction on the same photomask plane; wherein, the preset exposure areas include a plurality of target exposure areas spaced apart along the second direction; a second light-shielding area is disposed between adjacent target exposure areas; the size of the second light-shielding area is smaller than the minimum feature size of the photomask.

[0006] Optionally, the second light-blocking area has the same width as the target exposure area in the first direction.

[0007] Optionally, the ratio between the extension length of the target exposure area in the second direction and the extension length of the second light-shielding area in the second direction falls between 25 and 35.

[0008] Optionally, the ratio between the length and width of the preset exposure area or the first light-blocking area is greater than 9.

[0009] Another embodiment of this application provides a semiconductor structure, including: a substrate; a patterned photoresist layer; the patterned photoresist layer is located on the surface of the substrate, and the patterned photoresist layer is formed by photolithography using a photomask as described in the foregoing embodiments; the patterned photoresist layer includes a plurality of photoresist pattern structures corresponding to preset exposure areas or first light-shielding areas; wherein, the photoresist pattern structure includes a plurality of stabilizing portions corresponding to a plurality of second light-shielding areas respectively in a second direction, and standard portions located between adjacent stabilizing portions; the bottom of the stabilizing portion is wider than the bottom of the standard portion in a first direction.

[0010] Optionally, at the same height position relative to the base surface, the width of the stabilizing portion along the first direction is not less than the width of the standard portion along the first direction.

[0011] Optionally, the stabilizing portion has a first end and a second end respectively connected to different standard portions in the second direction; the width of the bottom of the stabilizing portion along the first direction gradually increases and then gradually decreases from the first end to the second end.

[0012] Another embodiment of this application provides a method for fabricating a semiconductor structure. The method includes: providing a substrate and coating a photoresist on the surface of the substrate; performing a photolithography process on the photoresist on the substrate surface using a photomask as described in the foregoing embodiments to form a patterned photoresist layer on the substrate surface; the patterned photoresist layer includes a plurality of photoresist pattern structures corresponding to preset exposure areas or first light-shielding areas; wherein the photoresist pattern structure includes a plurality of stabilizing portions corresponding to a plurality of second light-shielding areas in a second direction, and standard portions located between adjacent stabilizing portions; the bottom of the stabilizing portion is wider than the bottom of the standard portion in a first direction.

[0013] Another embodiment of this application provides a method for generating a photomask pattern, the photomask pattern being used to create a photomask as described in the foregoing embodiments; the method for generating the photomask pattern includes: obtaining an initial photomask pattern; the initial photomask pattern having a plurality of preset exposure areas spaced apart along a first direction; a first light-shielding area being disposed between adjacent preset exposure areas; the preset exposure areas or the first light-shielding area having a width in a first direction and a length extending along a second direction; the length being greater than the width; adding a plurality of sub-resolution auxiliary graphics as second light-shielding areas to the preset exposure areas along the second direction to generate a target photomask pattern; wherein the plurality of second light-shielding areas divide the preset exposure areas into a plurality of target exposure areas spaced apart along the second direction.

[0014] Optionally, the method for generating the photomask pattern further includes: performing optical proximity effect correction processing on the initial photomask pattern.

[0015] The unexpected effect of the various embodiments provided in this application is that by setting multiple sub-resolution second light-shielding areas at intervals along the length extension direction of the preset exposure area of ​​the photomask, the bottom of the photoresist pattern structure obtained after exposure is wider at the position corresponding to the second light-shielding area, thereby improving its torsional resistance in the width direction, thus improving the stability of the photoresist pattern structure and improving the problem of line inversion. Attached Figure Description

[0016] Figures 1a to 1c This is a schematic diagram illustrating the problem of reverse lines occurring in patterned photoresist layers formed by photolithography in related technologies.

[0017] Figure 2 This is a schematic diagram of a photomask provided for one embodiment of this application.

[0018] Figure 3 A schematic diagram of a semiconductor structure provided for another embodiment of this application.

[0019] Figure 4a and Figure 4b A cross-sectional comparison diagram of the standard part and the stable part provided for another embodiment of this application.

[0020] Figure 5 An ADI image of a patterned photoresist layer provided for another embodiment of this application.

[0021] Figure 6 This is a schematic diagram of a method for fabricating a semiconductor structure according to another embodiment of this application.

[0022] Figure 7 This is a schematic flowchart of a method for generating a photomask pattern, provided as another embodiment of this application.

[0023] Figure 8 This is a schematic diagram illustrating the changes in the photomask pattern in a method for generating a photomask pattern according to another embodiment of this application.

[0024] Figures 9a to 9c This is a schematic diagram comparing the results of photolithography using the photomask of this application with those using a conventional photomask.

[0025] Figures 10a to 10c This is a schematic diagram comparing the results of FEM tests on the same pattern using different photomasks.

[0026] Explanation of reference numerals in the attached figures:

[0027] 10. Photomask; 11. Preset exposure area; 12. First light-shielding area; 13. Target exposure area; 14. Second light-shielding area; 20. Semiconductor structure; 21. Substrate; 22. Patterned photoresist layer; 23. Photoresist pattern structure; 231. Stabilizing part; 232. Standard part; 31. Initial photomask pattern; 32. Intermediate pattern; 33. Target photomask pattern; AA, First direction; BB, Second direction. Detailed Implementation

[0028] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0029] In this application, the accompanying drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features.

[0030] Unless otherwise stated, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items. The singular forms "a," "the," and "the" as used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0031] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0032] In the description of this application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of simplifying the description of this application and do not indicate that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. In other words, they should not be construed as limitations on this application.

[0033] In the description of this application, unless otherwise expressly defined, the terms "installation," "connection," "linking," "fixing," "setting," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can also refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] Please see Figures 1a to 1c In related technologies, as process nodes become smaller, patterned photoresist layers formed through photolithography are increasingly prone to issues such as deformation and collapse of the photoresist pattern structure. For example, researchers have found that at process nodes of 55nm and above, the problem of inverted lines in patterned photoresist layers is virtually nonexistent, but starting from the 40nm process node, inverted lines easily appear within the process window, and become even more severe at the 28nm process node.

[0035] Specifically, in some manufacturing processes, such as the fabrication of metal layers, the patterned photoresist layer formed by photolithography typically has multiple photoresist pattern structures with relatively long extensions. These photoresist pattern structures are usually narrow in width, appearing as long, thin strips. Therefore, their stability is poor, and they are prone to deformation or twisting in the width direction, or even collapse, resulting in poor pattern transfer accuracy and affecting the accuracy of subsequent process steps. For example, Figure 1a and Figure 1b All images are ADI (After Develop Inspection) images produced using photolithography. Figure 1a The pattern structure of the photoresist is deformed. Figure 1b The middle section collapsed. Figure 1c The images obtained using the KLA tool for defect detection show that the photoresist pattern structure also exhibits deformation.

[0036] Therefore, it is necessary to provide an improved photomask that can improve the inverted lines problem of patterned photoresist layers formed using photolithography.

[0037] Please see Figure 2 One embodiment of this application provides a photomask 10. The photomask 10 has a plurality of preset exposure areas 11 arranged at intervals along a first direction, and a first light-blocking area 12 is provided between adjacent preset exposure areas 11.

[0038] In this embodiment, the preset exposure area 11 can be a specific area on the photomask 10 that is designed to transmit light. During the photolithography process, the photoresist covered by this area is exposed to light, allowing it to work in conjunction with the first light-shielding area 12 to form a pattern on the photoresist layer after development. Specifically, when a negative photoresist is used in the photolithography process, the preset exposure area 11 can correspond to the photoresist pattern structure in the developed patterned photoresist layer.

[0039] In this embodiment, the first light-shielding area 12 can be a specific area on the photomask 10 that is opaque to light. During the photolithography process, it prevents the photoresist covered by the area from being exposed to a light source, thus allowing it to work in conjunction with the preset exposure area 11 to define a pattern on the photoresist layer after development. Specifically, when a positive photoresist is used in the photolithography process, the first light-shielding area 12 can correspond to the photoresist pattern structure in the developed patterned photoresist layer.

[0040] In this embodiment, both the preset exposure area 11 and the first light-shielding area 12 can be spaced apart along a first direction. The first direction can be the arrangement direction of the preset exposure area 11 or the first light-shielding area 12, as shown in the reference. Figure 2 In the AA direction. The preset exposure area 11 and the first light-blocking area 12 are arranged in an alternating pattern in the first direction, that is, any preset exposure area 11 is adjacent to the first light-blocking area 12 in the first direction, and any first light-blocking area 12 is adjacent to the preset exposure area 11 in the first direction.

[0041] In this embodiment, the preset exposure area 11 or the first light-shielding area 12 has a width in a first direction and a length extending along a second direction, where the second direction is a direction perpendicular to the first direction on the same photomask plane. Figure 2 In the BB direction. Specifically, the preset exposure area 11 or the first light-shielding area 12 can be elongated, having a length and a width. The width of the preset exposure area 11 or the first light-shielding area 12 is its first extension distance along the first direction, and the length of the preset exposure area 11 or the first light-shielding area 12 is its second extension distance along the second direction.

[0042] In this embodiment, the length of the preset exposure area 11 or the first light-shielding area 12 is greater than its width. Optionally, the ratio between the length and width of the preset exposure area 11 or the first light-shielding area 12 is greater than 9. Specifically, since a more elongated photoresist pattern structure is more prone to inverted lines, it is necessary to improve the corresponding elongated preset exposure area 11 or the first light-shielding area 12 in the photomask 10.

[0043] In this embodiment, the spacing between adjacent preset exposure areas 11 can be the same as the width of the first light-shielding area 12 in the first direction, and the spacing between adjacent first light-shielding areas 12 can be the same as the width of the preset exposure area 11 in the first direction. The specific spacing can be flexibly set according to actual process requirements.

[0044] In this embodiment, the preset exposure area 11 includes a plurality of target exposure areas 13 arranged at intervals along a second direction, and a second light-shielding area 14 is provided between adjacent target exposure areas 13. Specifically, the preset exposure area 11 may be provided with a plurality of second light-shielding areas 14 in the second direction, and the preset exposure area 11 can be divided into a plurality of target exposure areas 13 by means of the plurality of second light-shielding areas 14.

[0045] In this embodiment, the second light-shielding area 14 is also a light-blocking region on the photomask 10, and the size of the second light-shielding area 14 is smaller than the minimum feature size of the photomask 10. Specifically, the second light-shielding area 14 can serve as a sub-resolution auxiliary pattern in the pattern of the photomask 10. Although the second light-shielding area 14 is opaque, because its size and spacing are outside the resolution limit of the photolithography system, it can, based on the diffraction effect, not only avoid interfering with the main pattern corresponding to the preset exposure area 11, but also improve the imaging quality and resolution.

[0046] Optionally, the second light-blocking area 14 has the same width as the target exposure area 13 in the first direction.

[0047] Optionally, the ratio between the extension length D1 of the target exposure area 13 in the second direction and the extension length D2 of the second light-shielding area 14 in the second direction falls between 25 and 35. Specifically, for example, the value of the extension length D1 of the target exposure area 13 in the second direction can be between 300 nm and 1000 nm, and the value of the extension length D2 of the second light-shielding area 14 in the second direction can be between 10 nm and 35 nm.

[0048] In this embodiment, an unexpected effect is that by setting multiple sub-resolution second light-shielding areas 14 at intervals along the length extension direction of the preset exposure area 11 of the photomask 10, the bottom of the photoresist pattern structure obtained after exposure is wider at the position corresponding to the second light-shielding area 14, thereby improving its torsional strength in the width direction, thus improving the stability of the photoresist pattern structure and improving the problem of line inversion.

[0049] Please see Figures 3 to 5 Another embodiment of this application provides a semiconductor structure 20, including: a substrate 21; a patterned photoresist layer 22; the patterned photoresist layer 22 is located on the surface of the substrate 21, and the patterned photoresist layer 22 is formed by photolithography using a photomask 10 as described in the foregoing embodiments.

[0050] In this embodiment, the patterned photoresist layer 22 may include multiple photoresist pattern structures 23 corresponding to preset exposure areas 11 or first light-shielding areas 12. Depending on the positive and negative types of the photoresist used, the multiple photoresist pattern structures 23 in the patterned photoresist layer 22 may respectively correspond to multiple preset exposure areas 11 or first light-shielding areas 12. Specifically, the photoresist pattern structures 23 are also arranged at intervals along the first direction in the patterned photoresist layer 22, and adjacent photoresist pattern structures 23 have trenches formed after exposure and development.

[0051] In this embodiment, since the preset exposure area 11 of the photomask 10 in the aforementioned embodiment has multiple second light-shielding areas 14 along the second direction, based on the optical proximity effect during the exposure process, the photoresist pattern structure 23 obtained after development also has multiple corresponding stabilizing portions 231 along the second direction. The positions of the stabilizing portions 231 in the second direction are consistent with the positions of the second light-shielding areas 14 in the second direction. Specifically, the multiple stabilizing portions 231 are also distributed at intervals in the second direction, dividing the photoresist pattern structure 23 into multiple standard portions 232 located between adjacent stabilizing portions 231.

[0052] In this embodiment, the morphologies of the stabilizing portion 231 and the standard portion 232 of the same photoresist pattern structure 23 are different. Specifically, refer to... Figure 3 , Figure 4a and Figure 4b ,in, Figure 4a This is a cross-sectional schematic diagram of standard part 232. Figure 4b This is a cross-sectional view of the stabilizing part 231. Figure 4a and Figure 4b The comparison shows that the side of the standard part 232 is closer to the surface of the substrate 21 than the side of the stable part 231. Alternatively, it can be understood that the angle between the side of the stable part 231 and the surface of the substrate 21 is smaller than the angle between the side of the standard part 232 and the surface of the substrate 21, meaning the taper of the stable part 231 is greater. Therefore, it can be understood that the bottom of the stable part 231 can be wider than the bottom of the standard part 232 in the first direction, resulting in stronger support and stability of the stable part 231 in the first direction. Thus, by using multiple stable parts 231 spaced apart in the second direction, the relatively slender photoresist pattern structure 23 can be reinforced, improving torsional resistance in the first direction. Figure 5 This is an ADI image of the patterned photoresist layer in this embodiment, such as... Figure 5 As shown, multiple photoresist pattern structures include standard parts and stabilizing parts, and the whole structure presents a "bamboo" shape. The stabilizing parts are shaped like "bamboo joints," which can provide reinforcement to multiple standard parts, improve stability, and improve the problem of ink reversal.

[0053] And continue to refer to Figure 3 , Figure 4a and Figure 4b During actual exposure, defocusing can easily occur, causing the width of the standard part 232 near the bottom to become smaller. Without the stabilizing part 231, the photoresist pattern structure 23, with its relatively long overall length, would be very prone to collapse. However, even in the event of defocusing, the stabilizing part 231, due to its larger bottom width and trapezoidal overall shape, provides better support and is less likely to collapse.

[0054] In some embodiments, at the same height relative to the surface of the base 21, the width of the stabilizing portion 231 along the first direction is not less than the width of the standard portion 232 along the first direction. This makes the overall stability of the stabilizing portion 231 stronger in the first direction, and its reinforcement effect on the standard portion 232 more significant.

[0055] In some embodiments, the stabilizing portion 231 has a first end and a second end respectively connected to different standard portions 232 in the second direction; the width of the bottom of the stabilizing portion 231 along the first direction gradually increases and then gradually decreases from the first end to the second end. Specifically, refer to... Figure 3 The width of the stabilizing portion 231 can gradually increase along the second direction from the width of an adjacent standard portion 232, and then gradually decrease to the width of another adjacent standard portion 232. This makes the connection between the stabilizing portion 231 and the standard portion 232 smoother, which can strengthen the standard portion 232 while reducing the impact on the overall shape of the photoresist pattern structure 23, thereby ensuring the pattern transfer accuracy of the photolithography process.

[0056] Please see Figure 6 Another embodiment of this application provides a method for fabricating a semiconductor structure, the method comprising the following steps:

[0057] S110: Provide a substrate and coat the surface of the substrate with photoresist.

[0058] S120: For the photoresist on the substrate surface, a photolithography process is performed using the photomask as described in the foregoing embodiments to form a patterned photoresist layer on the substrate surface; the patterned photoresist layer includes multiple photoresist pattern structures corresponding to preset exposure areas or first light-shielding areas.

[0059] The photoresist pattern structure includes a plurality of stabilizing portions corresponding to a plurality of second light-shielding areas in a second direction, and a standard portion located between adjacent stabilizing portions; the bottom of the stabilizing portion is wider than the bottom of the standard portion in a first direction.

[0060] For a detailed explanation of each step in the semiconductor structure fabrication method, please refer to the foregoing embodiments; further details will not be repeated here.

[0061] Please see Figure 7 and Figure 8 Another embodiment of this application provides a method for generating a photomask pattern, the photomask pattern being used to create a photomask as described in the foregoing embodiments. The method for generating the photomask pattern includes the following steps:

[0062] S210: Obtain an initial photomask pattern; the initial photomask pattern has a plurality of preset exposure areas arranged at intervals along a first direction; a first light-shielding area is provided between adjacent preset exposure areas; the preset exposure area or the first light-shielding area has a width in a first direction and a length extending along a second direction; the length is greater than the width.

[0063] S220: Along the second direction, add a plurality of sub-resolution auxiliary graphics as second light-shielding areas to the preset exposure area to generate a target photomask pattern; wherein the plurality of second light-shielding areas divide the preset exposure area into a plurality of target exposure areas arranged at intervals along the second direction.

[0064] In some embodiments, the method for generating the photomask pattern further includes: performing optical proximity correction processing on the initial photomask pattern.

[0065] In this embodiment, specifically, such as Figure 8 As shown, an initial photomask pattern 31 is first obtained, which has multiple preset exposure areas and multiple first shading areas. Then, optical proximity correction (OPC) processing is performed on the initial photomask pattern to form an intermediate pattern 32. For the intermediate pattern 32, multiple sub-resolution auxiliary patterns are added to the preset exposure areas, and a target photomask pattern 33 is output after detection and correction. The multiple sub-resolution auxiliary patterns added to the target photomask pattern 33 are used as second shading areas in the fabricated photomask.

[0066] In this embodiment, other parts and effects that are the same as in the foregoing embodiments can be referred to the foregoing embodiments, and will not be repeated here.

[0067] To verify and illustrate the effect of the photomask of this application, and the patterned photoresist layer formed using the photomask in the photolithography process, technicians performed a photolithography process on a conventional photomask without a second light-shielding area and the photomask of this application together for comparison. Figures 9a to 9c As shown, Figure 9a , Figure 9b and Figure 9cImages of patterned photoresist layers under three different exposure conditions are provided. Figure 9a The exposure dose is 39.8 mJ / cm², and the focus position offset is 0 nm. Figure 9b The dose is 38.8 mJ / cm², and the defocus is -10 nm. Figure 9c The dose is 38.3 mJ / cm², and the defocus is -20 nm. It can be seen that after the photolithography process, the photoresist pattern structure corresponding to the photomask pattern of a conventional photomask undergoes multiple deformations or collapses (at the location of the red dashed box), while the photoresist pattern structure corresponding to the photomask pattern of this application does not show deformation or collapse.

[0068] In addition, the technicians also used different photomasks to perform FEM (Focus Exposure Matrix) tests on the same pattern, and the results were as follows: Figure 10a , Figure 10b , Figure 10c As shown. Figure 10a , Figure 10b , Figure 10c The results of FEM tests were performed on a conventional photomask without a second shading area, a conventional photomask without a second shading area (with an anti-reflective coating), and the photomask of this application. Figure 10a and Figure 10b The DoF (Depth of Focus) value is 50nm. Figure 10c The DoF in the image is 80nm. It is evident that using the photomask of this application improves the process window by 60%.

[0069] It is understood that the specific examples in this document are only intended to help those skilled in the art better understand the embodiments of this application, and are not intended to limit the scope of the invention.

[0070] It is understood that in the various embodiments of this application, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0071] It is understood that the various embodiments described in this application can be implemented individually or in combination, and the embodiments of this application are not limited in this respect.

[0072] Unless otherwise stated, all technical and scientific terms used in the embodiments of this application have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items. The singular forms "a," "the," and "the" as used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0073] The above description is merely a specific embodiment of this application, but the scope of protection of this invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this invention should be determined by the scope of the claims.

Claims

1. A photomask, characterized in that, The photomask has a plurality of preset exposure areas arranged at intervals along a first direction; a first light-shielding area is provided between adjacent preset exposure areas; the preset exposure area or the first light-shielding area has a width in a first direction and a length extending along a second direction. The length is greater than the width; wherein, the first direction is the arrangement direction of the preset exposure area or the first light-shielding area; the second direction is the direction perpendicular to the first direction on the same photomask plane; The preset exposure area includes a plurality of target exposure areas arranged at intervals along the second direction; a second light-shielding area is provided between adjacent target exposure areas; the size of the second light-shielding area is smaller than the minimum feature size of the photomask.

2. The photomask according to claim 1, characterized in that, The second light-blocking area has the same width as the target exposure area in the first direction.

3. The photomask according to claim 2, characterized in that, The ratio between the extension length of the target exposure area in the second direction and the extension length of the second shading area in the second direction falls between 25 and 35.

4. The photomask according to claim 2, characterized in that, The ratio between the length and width of the preset exposure area or the first light-blocking area is greater than 9.

5. A semiconductor structure, characterized in that, include: Base; Patterned photoresist layer; The patterned photoresist layer is located on the surface of the substrate, and the patterned photoresist layer is formed by photolithography using the photomask as described in claim 1; the patterned photoresist layer includes multiple photoresist pattern structures corresponding to preset exposure areas or first light-shielding areas; The photoresist pattern structure includes multiple stabilizing portions corresponding to multiple second light-shielding areas in a second direction, and standard portions located between adjacent stabilizing portions; the bottom of the stabilizing portion is wider than the bottom of the standard portion in a first direction.

6. The semiconductor structure according to claim 5, characterized in that, At the same height relative to the base surface, the width of the stabilizing portion along the first direction is not less than the width of the standard portion along the first direction.

7. The semiconductor structure according to claim 6, characterized in that, The stabilizing part has a first end and a second end that are respectively connected to different standard parts in the second direction; the width of the bottom of the stabilizing part along the first direction gradually increases and then gradually decreases from the first end to the second end.

8. A method for fabricating a semiconductor structure, characterized in that, The preparation method includes: A substrate is provided, and photoresist is coated on the surface of the substrate; For the photoresist on the substrate surface, a photolithography process is performed using the photomask as described in claim 1 to form a patterned photoresist layer on the substrate surface; the patterned photoresist layer includes a plurality of photoresist pattern structures corresponding to preset exposure areas or first light-shielding areas; wherein, the photoresist pattern structure includes a plurality of stabilizing portions corresponding to a plurality of second light-shielding areas respectively in a second direction, and standard portions located between adjacent stabilizing portions; the bottom of the stabilizing portion is wider than the bottom of the standard portion in a first direction.

9. A method for generating a photomask pattern, characterized in that, The photomask pattern is used to create the photomask as described in claim 1; The method for generating the photomask pattern includes: An initial photomask pattern is obtained; the initial photomask pattern has a plurality of preset exposure areas spaced apart along a first direction; a first light-shielding area is provided between adjacent preset exposure areas; the preset exposure area or the first light-shielding area has a width in a first direction and a length extending along a second direction; the length is greater than the width. Along the second direction, multiple sub-resolution auxiliary graphics, serving as second light-shielding areas, are added to the preset exposure area to generate a target photomask pattern; wherein, the multiple second light-shielding areas divide the preset exposure area into multiple target exposure areas arranged at intervals along the second direction.

10. The method for generating a photomask pattern according to claim 9, characterized in that, The method for generating the photomask pattern further includes: The initial photomask pattern is subjected to optical proximity effect correction processing.

Images