Photomask and exposure and development method
By setting up a combination of Gemini photomasks with shading structures on the photoresist film layer, the problems of light leakage at the edges of traditional photomasks and deformation of the stitching area are solved, and the accuracy and quality improvement of the lithographic pattern is achieved.
Patent Information
- Application Number
- CN202310694192.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-12
- Publication Date
- 2024-12-20
AI Technical Summary
In traditional 2.5D integrated circuits, in the stitching exposure technology of the silicon interposer layer, light leakage or stray light is easily generated at the edge of the photomask, resulting in damage to the shape of the photoresist pattern, and the repeated exposure and pattern deformation of the stitching area are difficult to solve. solve.
Using a photomask composed of the first sub-photomask and the second sub-photomask, the blocking slave and the blocking main part are provided on the photoresist film layer to prevent light from irradiating to the non-target area, ensuring that The shape accuracy of the lithographic patterns weakens the impact of pattern diffraction and light refraction on the projected region.
It effectively eliminates the deformation and graphic distortion problems of lithographic graphics in the stitching area, ensures the shape accuracy and quality of lithographic graphics, and reduces the occurrence of graphic distortion.
Smart Images
Figure CN119165723A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present disclosure relate to the field of semiconductor technology, and in particular, to a photomask and an exposure and development method. Background Art
[0002] In order to achieve better performance and lower power consumption, traditional 2.5D integrated circuits integrate storage / logic circuits / chips in a single package structure by using Si interposer and through silicon via (TSV) technology. In the design of chip-on-wafer-on-substrate (CoWoS), the formation of a large silicon interposer requires stitching exposure technology to avoid the limitation of the size of the silicon middle layer by the mask size. When exposing to form a photomask pattern corresponding to a large middle layer, a typical photolithography process requires the use of multiple small photomasks for stitching exposure to form the required photomask pattern. In the process of using a small photomask to form a photomask pattern on a positive photoresist, the edge of the small mask is prone to light leakage or stray light, which damages the exposure of the photoresist in the non-target area, thereby affecting the shape of the photomask pattern. For example, the stitching area between two small photomask patterns is repeatedly exposed, and the mask pattern in the stitching area is severely deformed. Summary of the invention
[0003] The embodiments of the present disclosure provide a photomask and an exposure and development method, which can optimize the mask pattern of the stitching area.
[0004] A photomask, used for forming a photolithographic pattern on a photoresist film layer composed of positive photoresist on a substrate surface, comprises: a first sub-photomask and a second sub-photomask;
[0005] The first sub-photomask has a first main pattern area and a first stitching area arranged side by side along a first direction, the first stitching area includes a first shielding slave portion and a first sub-pattern area arranged side by side along the first direction, the first shielding slave portion is located at a side of the first sub-pattern area away from the first main pattern area, and the first shielding slave portion is used to shield light to prevent light from irradiating a first projection area of the first shielding slave portion on the photoresist film layer when the first sub-photomask is used for exposure and development;
[0006] A first shielding main portion is formed in the first main graphic area and the first sub-graphic area, and a second shielding main portion is formed in the second sub-photomask. The first shielding main portion and the second shielding main portion are both used to block light to form a photolithography pattern on the photoresist film layer. The second shielding main portion covers the first projection area in a second projection area on the photoresist film layer to form a photolithography pattern on the photoresist film layer corresponding to the first projection area.
[0007] In one embodiment, the first shielding slave portion and the first shielding master portion are made of the same material.
[0008] In one embodiment, the first shielding slave portion and the first shielding master portion are made of different materials.
[0009] In one embodiment, the first shielding portion includes:
[0010] a first blocking layer, close to the first sub-pattern area, and made of the same material as the first shielding main portion;
[0011] a second blocking layer, facing away from the first sub-pattern area, and having a different constituent material from the first shielding main portion;
[0012] The transmittance of the first blocking layer to the incident light is less than or equal to the transmittance of the second blocking layer to the incident light.
[0013] In one embodiment, in the first direction, a first width of the first shielding portion is equal to a second width of the first sub-pattern area.
[0014] In one embodiment, the second sub-photomask has a second main graphic area and a second stitching area arranged side by side in the first direction, the second stitching area includes a second shielding slave portion and a second sub-graphic area arranged side by side along the first direction, a second shielding main portion is formed in the second main graphic area and the second sub-graphic area, the second shielding slave portion is located at a side of the second sub-graphic area away from the second main graphic area, and the second shielding slave portion is used to shield light to prevent light from irradiating a third projection area of the second shielding slave portion on the photoresist film layer when the second sub-photomask is used for exposure and development;
[0015] There is no overlapping area between the third projection area and the first projection area.
[0016] In one of the embodiments, the first projection area and the third projection area are spaced apart, and the spacing distance between the first projection area and the third projection area is greater than or equal to the alignment deviation of the lithography machine.
[0017] In one embodiment, the first shielding portion and the second shielding portion are made of at least partially the same material; and the shape of the first shielding portion and the shape of the second shielding portion are mirror images of each other.
[0018] The above-mentioned photolithography mask includes a first sub-photomask and a second sub-photomask. The first shielding slave portion of the first sub-photomask is located on the side of the first sub-graphic area away from the first main graphic area, so that when the first sub-photomask is used for exposure and development, light will not irradiate the first projection area of the first shielding slave portion on the photoresist film layer. The second projection area of the second shielding main portion in the second sub-photomask on the photoresist film layer covers the first projection area, so that the first projection area is only exposed by the second sub-photomask, eliminating the influence of pattern diffraction and light refraction on the photolithography pattern formed in the first projection area, and weakening the problem of pattern deformation caused by excessive exposure of the photolithography pattern in the overlapping area of the projections of the first sub-photomask and the second sub-photomask on the photoresist film layer.
[0019] The present disclosure also provides a method for exposure and development, comprising:
[0020] A substrate is provided, wherein a photoresist film layer composed of a positive photoresist is provided on the surface of the substrate, wherein the photoresist film layer comprises a first exposure area, a stitching exposure area and a second exposure area arranged side by side, wherein the stitching exposure area is located between the first exposure area and the second exposure area and is composed of a first stitching exposure area close to the first exposure area and a second stitching exposure area close to the second exposure area;
[0021] Providing a photomask as described above;
[0022] Using a first sub-photomask in the photomask to expose and develop the first exposure area and the first stitching exposure area to form a photolithography pattern, the projection of the first shielding portion on the substrate coincides with the second stitching exposure area;
[0023] The second sub-photomask in the photomask is used to expose and develop at least the second exposure area and the second stitching exposure area to form a photolithography pattern, and the projection of the second sub-photomask on the photoresist film layer covers the stitching exposure area and the second exposure area.
[0024] In the above-mentioned exposure and development method, the first sub-photomask is used to expose and develop the first exposure area and the first stitched exposure area. The projection of the first shielding portion on the substrate coincides with the second stitched exposure area, so that when the first sub-photomask is used for exposure and development, the light will not irradiate the second exposure area, that is, the second exposure area is only exposed by the second sub-photomask, eliminating the influence of pattern diffraction and light refraction on the photolithography pattern formed in the second exposure area, and weakening the deformation problem of the photolithography pattern on the stitched exposure area. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or related technologies, the drawings required for use in the embodiments or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0026] Figure 1 is a schematic top view of a photomask in one embodiment;
[0027] Figure 2 for Figure 1 A cross-sectional schematic diagram of the first shielding portion along the AA direction in a corresponding embodiment;
[0028] Figure 3 for Figure 1 A cross-sectional schematic diagram of the second shielding portion along the AA direction in a corresponding embodiment;
[0029] Figure 4 is a schematic top view of a photomask in yet another embodiment;
[0030] Figure 5 FIG. 4 is a schematic flow chart of an exposure and development method in one embodiment.
[0031] Description of reference numerals:
[0032] 100, first sub-photomask; 102, first shielding main part; 104, first blocking layer; 106, second blocking layer; 108, first substrate; 200, second sub-photomask; 202, second shielding main part; 204, third blocking layer; 206, fourth blocking layer; 208, second substrate; 302, third sub-photomask; 402, fourth sub-photomask; A1, first main graphic area; A2, second main graphic area; A3, third main graphic area; B1, the first stitching area; B2, the second stitching area; B3, the third stitching area; B4, the fourth stitching area; B5, the fifth stitching area; B11, the first sub-graphic area; B12, the first shielding portion; B21, the second sub-graphic area; B22, the second shielding portion; B31, the third sub-graphic area; B32, the third shielding portion; B41, the fourth sub-graphic area; B42, the fourth shielding portion; B51, the fifth sub-graphic area; B52, the fifth shielding portion. DETAILED DESCRIPTION
[0033] In order to facilitate understanding of the embodiments of the present disclosure, the embodiments of the present disclosure will be described more fully below with reference to the relevant drawings. The preferred embodiments of the embodiments of the present disclosure are shown in the drawings. However, the embodiments of the present disclosure can be implemented in many different forms and are not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the embodiments of the present disclosure more thorough and comprehensive.
[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the technical field of the disclosed embodiments. The terms used herein in the specification of the disclosed embodiments are only for the purpose of describing specific embodiments and are not intended to limit the disclosed embodiments. The term "and / or" used herein includes any and all combinations of one or more related listed items.
[0035] In the description of the embodiments of the present disclosure, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "inside", "outside", etc. indicating orientations or positional relationships are based on the methods or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present disclosure.
[0036] It is understood that the terms "first", "second", etc. used in the present disclosure may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of the present disclosure, a first sub-light mask may be referred to as a second sub-light mask, and similarly, a second sub-light mask may be referred to as a first sub-light mask. Both the first sub-light mask and the second sub-light mask are sub-light masks, but they are not the same sub-light mask.
[0037] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the description of the present disclosure, the meaning of "several" is at least one, such as one, two, etc., unless otherwise clearly and specifically defined.
[0038] Figure 1 FIG. 1 is a schematic top view of a photomask in one embodiment. Figure 1As shown, in this embodiment, a photomask is provided for forming a photolithographic pattern on a photoresist film layer composed of a positive photoresist on a substrate surface, the photomask comprising: a first sub-photomask 100 and a second sub-photomask 200, wherein the projections of the first sub-photomask 100 and the second sub-photomask 200 on the photoresist film layer are arranged along a first direction X; the first sub-photomask 100 comprises a first main pattern area A1 and a first stitching area B1 arranged side by side along the first direction X, the first stitching area B1 comprises a first sub-pattern area B11 and a first shielding slave portion B12 arranged side by side along the first direction X, the first shielding slave portion B12 being located on a side of the first sub-pattern area B11 away from the first main pattern area A1, that is, along the first direction X, the first main pattern area A1, the first sub-pattern area B11 and the first shielding slave portion B12 are arranged in sequence. A first main graphic area A1 is in contact with a first sub-graphic area B11, and the first sub-graphic area B11 is in contact with a first shielding slave part B12. The first shielding slave part B12 is used to shield light to prevent light from irradiating a first projection area of the first shielding slave part B12 on the photoresist film layer when the first sub-photomask 100 is used for exposure and development; a first shielding main part 102 is formed in the first main graphic area A1 and the first sub-graphic area B11, and a second shielding main part 202 is formed in the second sub-photomask 200. Both the first shielding main part 102 and the second shielding main part 202 are used to shield light to form a photolithography pattern on the photoresist film layer. The second projection area of the second shielding main part 202 on the photoresist film layer covers the first projection area to form a photolithography pattern on the photoresist film layer corresponding to the first projection area. The first shielding portion B12 serves as a blocking portion for exposure and development, thereby avoiding the problem of light leakage or stray light generation at the edge of the first shielding portion B12 of the first sub-mask 100, which affects the shape of the photolithography pattern.
[0039] The above-mentioned photolithography mask includes a first sub-photomask 100 and a second sub-photomask 200. The first shielding slave portion B12 in the first sub-photomask 100 is located on the side of the first sub-graphic area B11 away from the first main graphic area A1, so that when the first sub-photomask 100 is used for exposure and development, light will not irradiate the first projection area of the first shielding slave portion B12 on the photoresist film layer. The second projection area of the second shielding main portion 202 in the second sub-photomask 200 on the photoresist film layer covers the first projection area, so that the first projection area is only exposed by the second sub-photomask 200, eliminating the influence of pattern diffraction and light refraction on the photolithography pattern formed in the first projection area, and weakening the pattern distortion problem of the photolithography pattern in the overlapping area of the projections of the first sub-photomask 100 and the second sub-photomask 200 on the photoresist film layer.
[0040] In one embodiment, the first shielding slave part B12 and the first shielding main part 102 are made of the same material, and the first shielding slave part B12 can be formed while preparing the first shielding main part 102, which is simple in process and convenient in operation. Exemplarily, the first shielding slave part B12 and the first shielding main part 102 are made of metal chromium.
[0041] In one of the embodiments, the constituent materials of the first shielding slave portion B12 and the first shielding main portion 102 are different, and the constituent materials of the first shielding slave portion B12 can be adjusted as needed to further reduce the problem of graphic distortion of the lithography pattern in the overlapping area of the projections of the first sub-photomask 100 and the second sub-photomask 200 on the photoresist film layer.
[0042] Figure 2 for Figure 1 A cross-sectional schematic diagram of the first shielding portion along the AA direction in a corresponding embodiment is shown in FIG. Figure 2 As shown, in one embodiment, the first shielding portion B12 includes: a first barrier layer 104 and a second barrier layer 106 arranged along the first direction X, wherein the first barrier layer 104 is close to the first sub-pattern area B11, the second barrier layer 106 is away from the first sub-pattern area B11, and the transmittance of the first barrier layer 104 to the incident light is less than or equal to the transmittance of the second barrier layer 106 to the incident light. Exemplarily, the transmittance of the first barrier layer 104 to the incident light includes 0% to 50%, such as 0%, 2%, 4%, 10%, 15%, 20%, 25%, 30%, 50%, etc., and the transmittance of the second barrier layer 106 to the incident light includes 30% to 90%, such as 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, 90%, etc.
[0043] During the exposure and development process, the position close to the first sub-pattern area B11 is affected by the exposure and development more than the position away from the first sub-pattern area B11. This setting reduces the restriction on the transmittance of the constituent material of the second blocking layer 106 to the incident light while ensuring that the distortion of the lithography pattern is not affected, thereby reducing the process cost to a certain extent.
[0044] Continue to refer Figure 2, exemplarily, the transmittance of the material constituting the first barrier layer 104 to the incident light is equal to the transmittance of the material constituting the second barrier layer 106 to the incident light, and in the second direction Y perpendicular to the first sub-photomask 100, the thickness T1 of the first barrier layer 104 is greater than the thickness T2 of the second barrier layer 106, so that the transmittance of the first barrier layer 104 to the incident light is less than the transmittance of the second barrier layer 106 to the incident light, that is, the transmittance of the first barrier layer 104 to the incident light can be adjusted by adjusting the thickness T1 of the first barrier layer 104, and the transmittance of the second barrier layer 106 to the incident light can be adjusted by adjusting the thickness T2 of the second barrier layer 106. The second direction Y is perpendicular to the first direction X. Optionally, the constituent material of the first barrier layer 104 and the constituent material of the second barrier layer 106 are the same, and exemplarily, the constituent material of the first barrier layer 104, the constituent material of the second barrier layer 106 and the constituent material of the first shielding main portion 102 are the same material. Optionally, the constituent material of the first barrier layer 104 and the constituent material of the second barrier layer 106 are different.
[0045] In other embodiments, the transmittance of the material of the first barrier layer 104 to the incident light is less than the transmittance of the material of the second barrier layer 106 to the incident light. In this case, the material of the first barrier layer 104 is different from the material of the second barrier layer 106. In the second direction Y perpendicular to the first sub-photomask 100, the thickness T1 of the first barrier layer 104 is equal to or less than the thickness T2 of the second barrier layer 106. It can be understood that by setting the thickness T1 of the first barrier layer 104 equal to the thickness T2 of the second barrier layer 106, the effect of the uneven surface of the first sub-photomask 100 on the pattern distortion of the photolithographic pattern can be eliminated.
[0046] like Figure 2 As shown, the first sub-photomask 100 is located on a first substrate 108. By way of example, the material constituting the first substrate 108 includes quartz glass.
[0047] Furthermore, the constituent material of the first barrier layer 104 is the same as the constituent material of the first shielding main portion 102 ; the constituent material of the second barrier layer 106 is different from the constituent material of the first shielding main portion 102 .
[0048] In one embodiment, in the first direction X, the first width of the first shielding portion B12 is equal to the second width of the first sub-pattern area B11. With this arrangement, the purpose of achieving in the first direction X that the area of the first stitching area B1 in the projection area on the photolithography mask layer that is exposed and developed through the first sub-photomask 100 is equal to the area of the second sub-photomask 200 that is exposed and developed, so that the photolithography pattern of the first stitching area B1 in the projection area on the photolithography mask layer is affected in the same way by pattern diffraction and light refraction, which can be used to determine the abnormality of the first sub-photomask 100 and the second sub-photomask 200.
[0049] It is understandable that in the first direction X, the first width of the first shielding portion B12 is greater than or equal to the first preset width, and the first preset width is the maximum length of the photoresist mask layer affected by pattern diffraction and light refraction in the first direction X when the first sub-mask 100 is used for exposure and development.
[0050] Continue to refer Figure 1 In one embodiment, the second sub-mask 200 has a second main graphic area A2 and a second stitching area B2 arranged side by side in a first direction X, the second stitching area B2 includes a second sub-graphic area B21 and a second shielding slave portion B22 arranged side by side along the first direction X, the second shielding slave portion B22 is located on a side of the second sub-graphic area B21 away from the second main graphic area A2, that is, along the first direction X, the second main graphic area A2, the second sub-graphic area B21 and the second shielding slave portion B22 are arranged in sequence, and the second main graphic area A2 is connected to the second sub-graphic area B21. The second sub-graphic area B21 is in contact with the second shielding slave part B22, and a second shielding main part 202 is formed in the second main graphic area A2 and the second sub-graphic area B21. The second shielding slave part B22 is used to block light to prevent the light from irradiating the third projection area of the second shielding slave part B22 on the photoresist film layer when the second sub-photomask 200 is used for exposure and development; wherein the third projection area and the first projection area do not overlap, so that the projection areas of the first sub-photomask 100 and the second sub-photomask 200 on the photoresist film layer are both formed with photolithography graphics.
[0051] In one embodiment, the first projection area and the third projection area are adjacent to each other, so that the first projection area is exposed and developed by the second sub-mask 200 to form a photolithography pattern, and the third projection area is exposed and developed by the first sub-mask 100 to form a photolithography pattern, and there is no repeated exposure and development portion of the first sub-mask 100 and the second sub-mask 200 in the total projection area on the photoresist mask layer, thereby minimizing the problem of pattern distortion of the photolithography pattern. At the same time, the second shielding portion B22 serves as a blocking portion for exposure and development, thereby avoiding the problem of light leakage or stray light generated at the edge of the second shielding portion B22 of the second sub-mask 100, which affects the shape of the photolithography pattern.
[0052] In one embodiment, the first projection area and the third projection area are spaced apart, and the spacing distance between the first projection area and the third projection area is greater than or equal to the alignment deviation of the lithography machine. Specifically, the first projection area and the third projection area are spaced apart in the first direction X, and the spacing distance between the first projection area and the second projection area in the first direction X is greater than or equal to the alignment deviation of the lithography machine, so as to avoid the problem that the alignment deviation of the lithography machine causes an overlap area between the first projection area and the third projection area, and in the process of using the first sub-mask 100 and the second sub-mask 200 for exposure and development, the overlap area between the first projection area and the third projection area is not exposed and developed, and the lithography pattern is partially missing, which affects the performance of the semiconductor structure. Exemplarily, the spacing distance between the first projection area and the third projection area in the first direction X is greater than or equal to 0.15um.
[0053] In one of the embodiments, the constituent materials of the second shielding slave portion B22 and the second shielding main portion 202 are different, and the constituent materials of the second shielding slave portion B22 can be adjusted as needed to further reduce the problem of graphic distortion of the photolithography pattern due to overexposure in the overlapping area of the projections of the first sub-photomask 100 and the second sub-photomask 200 on the photoresist film layer.
[0054] In one embodiment, the material of the second shielding slave portion B22 and the material of the second shielding main portion 202 are at least partially the same.
[0055] Optionally, the second shielding slave part B22 and the second shielding main part 202 are made of the same material, and the second shielding slave part B22 can be formed while preparing the second shielding main part 202, which is simple in process and convenient in operation. Exemplarily, the second shielding slave part B22 and the second shielding main part 202 are made of metal chromium.
[0056] Figure 3 for Figure 1 A cross-sectional schematic diagram of the second shielding portion along the AA direction in a corresponding embodiment is shown in FIG. Figure 3 As shown, in one embodiment, the second shielding portion B22 includes: a third barrier layer 204 and a fourth barrier layer 206 arranged along the first direction X, wherein the third barrier layer 204 is close to the second sub-pattern area B21, the fourth barrier layer 206 is away from the second sub-pattern area B21, and the transmittance of the third barrier layer 204 to the incident light is less than or equal to the transmittance of the fourth barrier layer 206 to the incident light. Exemplarily, the transmittance of the third barrier layer 204 to the incident light includes 0% to 50%, such as 0%, 2%, 4%, 10%, 15%, 20%, 25%, 30%, 50%, etc., and the transmittance of the fourth barrier layer 206 to the incident light includes 30% to 90%, such as 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, 90%, etc.
[0057] During the exposure and development process, the position close to the second sub-pattern area B21 is affected by the exposure and development more than the position away from the second sub-pattern area B21. This setting reduces the restriction on the transmittance of the constituent material of the fourth barrier layer 206 to the incident light while ensuring that the distortion of the lithography pattern is not affected, thereby reducing the process cost to a certain extent.
[0058] Exemplarily, the transmittance of the material of the third barrier layer 204 to the incident light is equal to the transmittance of the material of the fourth barrier layer 206 to the incident light. In the second direction Y perpendicular to the second sub-mask 200, the thickness T3 of the third barrier layer 204 is greater than the thickness T4 of the fourth barrier layer 206, so that the transmittance of the third barrier layer 204 to the incident light is less than the transmittance of the fourth barrier layer 206 to the incident light, that is, the transmittance of the third barrier layer 204 to the incident light can be adjusted by adjusting the thickness T3 of the third barrier layer 204, and the transmittance of the fourth barrier layer 206 to the incident light can be adjusted by adjusting the thickness T4 of the fourth barrier layer 206. The second direction Y is perpendicular to the first direction X. Optionally, the constituent material of the third barrier layer 204 and the constituent material of the fourth barrier layer 206 are the same. Exemplarily, the constituent material of the third barrier layer 204, the constituent material of the fourth barrier layer 206 and the constituent material of the second shielding main portion 202 are the same material. Optionally, the constituent material of the third barrier layer 204 and the constituent material of the fourth barrier layer 206 are different.
[0059] In other embodiments, the transmittance of the material constituting the third barrier layer 204 to the incident light is less than the transmittance of the material constituting the fourth barrier layer 206 to the incident light. In this case, the constituent materials of the third barrier layer 204 and the constituent materials of the fourth barrier layer 206 are different, and in the second direction Y perpendicular to the second sub-mask 200, the thickness T3 of the third barrier layer 204 is equal to or less than the thickness T4 of the fourth barrier layer 206. It can be understood that by setting the thickness T3 of the third barrier layer 204 to be equal to the thickness T4 of the fourth barrier layer 206 (such as Figure 3 As shown), the influence of the uneven surface of the second sub-mask 200 on the pattern distortion of the lithography pattern can be eliminated.
[0060] like Figure 3 As shown, the second sub-mask 200 is located on a second substrate 208. By way of example, the second substrate 208 is made of quartz glass.
[0061] Furthermore, the constituent material of the third barrier layer 204 is the same as the constituent material of the second main shielding portion 202 ; the constituent material of the fourth barrier layer 206 is different from the constituent material of the second main shielding portion 202 .
[0062] In one embodiment, in the first direction X, the third width of the second shielding portion B22 is equal to the fourth width of the second sub-pattern area B21. With this arrangement, the purpose of achieving in the first direction X that the area of the second stitching area B2 in the projection area on the photolithography mask layer exposed and developed by the second sub-photomask 200 is equal to the area exposed and developed by the first sub-photomask 100 is achieved, so that the photolithography pattern of the second stitching area B2 in the projection area on the photolithography mask layer is affected by the pattern diffraction and light refraction in the same manner, which can be used to determine the abnormality of the first sub-photomask 100 and the second sub-photomask 200.
[0063] It is understandable that in the first direction X, the third width of the second shielding portion B22 is greater than or equal to the second preset width, and the second preset width is the maximum length of the photoresist mask layer affected by pattern diffraction and light refraction in the first direction X when the second sub-mask 200 is used for exposure and development.
[0064] In one embodiment, the constituent material of the first shielding secondary part B12 is the same as the constituent material of the second shielding secondary part B22, which simplifies the process steps for preparing the first shielding secondary part B12 and the second shielding secondary part B22. In other embodiments, the constituent material of the first shielding secondary part B12 is different from the constituent material of the second shielding secondary part B22 or is partially the same.
[0065] In one embodiment, the shape of the first shielding portion B12 and the shape of the second shielding portion B22 are mirror images of each other.
[0066] In one embodiment, the shape of the first shielding main portion 102 and the shape of the second shielding main portion 202 are mirror images or the same as each other.
[0067] Exemplarily, when the shapes of the first shielding slave portion B12 and the second shielding slave portion B22 are mirror images of each other, and the shapes of the first shielding main portion 102 and the second shielding main portion 202 are mirror images of each other, the same mask plate can be used to form the first sub-mask 100 and the second sub-mask 200.
[0068] Exemplarily, the first stitching area B1 and the second stitching area B2 overlap, which is the overlapping area of the projections of the first sub-mask 100 and the second sub-mask 200 on the photoresist film layer. Optionally, in the first direction X, the first width of the first shielding portion B12 is equal to the fourth width of the second sub-patterning area B21, and the second width of the first sub-patterning area B11 is equal to the third width of the second shielding portion B22. This setting can avoid the problem of pattern distortion of the photolithographic pattern caused by overexposure of the first stitching area B1 and the second stitching area B2.
[0069] Exemplarily, the first stitching area B1 and the second stitching area B2 overlap, which is the overlapping area of the projections of the first sub-photomask 100 and the second sub-photomask 200 on the photoresist film layer. Optionally, in the first direction X, the first width of the first shielding portion B12 is less than the fourth width of the second sub-patterning area B21, the second width of the first sub-patterning area B11 is greater than the third width of the second shielding portion B22, and the first difference between the fourth width and the first width, and the second difference between the second width and the third width are both greater than or equal to the alignment deviation of the lithography machine. This setting can avoid the problem that a part of the photoresist film layer cannot be exposed due to the alignment deviation of the lithography machine.
[0070] Exemplarily, the first sub-photomask 100 and the second sub-photomask 200 are rectangular structures.
[0071] Figure 4 FIG. 1 is a schematic top view of a photomask in another embodiment. Figure 4As shown, in this embodiment, the photomask further includes a third sub-photomask 300 and a fourth sub-photomask 400, wherein the projections of the third sub-photomask 300 and the fourth sub-photomask 400 on the photoresist film layer are arranged along the first direction X, and the projections of the first sub-photomask 100 and the third sub-photomask 300 on the photoresist film layer, and the projections of the second sub-photomask 200 and the fourth sub-photomask 400 on the photoresist film layer are arranged along the third direction Z; the third sub-photomask 300 has a third main graphic area A3 and a third stitching area B3 arranged side by side along the first direction X, and the third stitching area B3 includes a third sub-graphic area B31 and a third shielding slave portion B32 arranged side by side along the first direction X, and the third shielding slave portion B32 is located on the side of the third sub-graphic area B31 away from the third main graphic area A3, that is, along the first direction X, the third main graphic area A3, the third sub-graphic area A3 and the third sub-graphic area B3 are arranged side by side. Area B31 and the third shielding slave part B32 are arranged in sequence, and the third main graphic area A3 is in contact with the third sub-graphic area B31, and the third sub-graphic area B31 is in contact with the third shielding slave part B32. The third shielding slave part B32 is used to block light to prevent the light from irradiating the fourth projection area of the third shielding slave part B32 on the photoresist film layer when the third sub-photomask 300 is used for exposure and development; a third shielding main part 302 is formed in the third main graphic area A3 and the third sub-graphic area B31, and a fourth shielding main part 402 is formed in the fourth sub-photomask 300. The third shielding main part 302 and the fourth shielding main part 402 are both used to block light to form a photolithography pattern on the photoresist film layer; the fourth shielding main part 402 covers the fourth projection area in the fifth projection area on the photoresist film layer to form a photolithography pattern on the photoresist film layer corresponding to the fourth projection area. The first sub-mask 100 further includes a fourth stitching area B4 arranged side by side with the first main graphic area A1 along the third direction Z. The fourth stitching area B4 includes a fourth sub-graphic area B41 and a fourth shielding slave portion B42 arranged side by side along the third direction Z. The fourth shielding slave portion B42 is located on a side of the fourth sub-graphic area B41 away from the first main graphic area A1. That is, along the third direction Z, the first main graphic area A1, the fourth sub-graphic area B41 and the fourth shielding slave portion B42 are arranged in sequence, and the first main graphic area A1 and the fourth sub-graphic area B41 are arranged side by side. 1, the fourth sub-pattern area B41 is in contact with the fourth shielding slave part B42, and the fourth shielding slave part B42 is used to shield light to prevent light from irradiating the sixth projection area of the fourth shielding slave part B42 on the photoresist film layer when the first sub-photomask 100 is used for exposure and development; the fourth sub-pattern area B41 is also formed with a first shielding master part 102, and the seventh projection area of the third shielding master part 302 on the photoresist film layer covers the sixth projection area to form a photolithography pattern on the photoresist film layer corresponding to the sixth projection area. Among them, the projection of the first extension overlap area where the extension direction of the first sub-pattern area B11 overlaps with the extension direction of the fourth sub-pattern area B41 on the photoresist film layer is exposed and developed by the first sub-photomask 100.
[0072] Exemplarily, the second sub-mask 200 further has a fifth stitching area B5 arranged side by side with the second main graphic area A2 along the third direction Z, the fifth stitching area B5 includes a fifth sub-graphic area B51 and a fifth shielding slave portion B52 arranged side by side along the third direction Z, the fifth shielding slave portion B52 is located on the side of the fifth sub-graphic area B51 away from the second main graphic area A2, that is, along the third direction Z, the second main graphic area A2, the fifth sub-graphic area B51 and the fifth shielding slave portion B52 are arranged in sequence, and the second main graphic area A2 and the fifth sub-graphic area B51 are arranged side by side. The fifth sub-pattern area B51 is in contact with the fifth shielding slave part B52, and the fifth shielding slave part B52 is used to shield light to prevent the light from irradiating the eighth projection area of the fifth shielding slave part B52 on the photoresist film layer when the second sub-photomask 100 is used for exposure and development; the fifth sub-pattern area B51 is also formed with a second shielding master part 202, and the ninth projection area of the fourth shielding master part 402 on the photoresist film layer covers the eighth projection area to form a photolithography pattern on the photoresist film layer corresponding to the eighth projection area. Among them, the projection of the second extension overlap area where the extension direction of the second sub-pattern area B21 overlaps with the extension direction of the fifth sub-pattern area B51 on the photoresist film layer is exposed and developed by the second sub-photomask 200.
[0073] It can be understood that the projection of the first stitching area B1 on the photoresist film layer is the overlapping part of the projection areas of the first sub-photomask 100 and the second sub-photomask 200 on the photoresist film layer, the projection of the fourth stitching area B4 on the photoresist film layer is the overlapping part of the projection areas of the first sub-photomask 100 and the third sub-photomask 300 on the photoresist film layer, the projection of the third stitching area B3 on the photoresist film layer is the overlapping part of the projection areas of the third sub-photomask 300 and the fourth sub-photomask 400 on the photoresist film layer, and the projection of the fifth stitching area B5 on the photoresist film layer is the overlapping part of the projection areas of the second sub-photomask 200 and the fourth sub-photomask 400 on the photoresist film layer.
[0074] It can be understood that the definition of the third sub-photomask 300 is similar to that of the first sub-photomask 100 , and the definition of the fourth sub-photomask 400 is similar to that of the second sub-photomask 200 , and thus will not be described in detail.
[0075] Figure 5 FIG. 1 is a schematic flow chart of an exposure and development method in one embodiment. Figure 5 As shown, in this embodiment, a method for exposure and development is provided, comprising:
[0076] S102, providing a substrate, wherein a photoresist film layer composed of positive photoresist is formed on the surface of the substrate.
[0077] A substrate is provided, wherein the substrate surface has a photoresist film layer composed of a positive photoresist, wherein the photoresist film layer comprises a first exposure area, a stitching exposure area and a second exposure area arranged side by side, wherein the stitching exposure area is located between the first exposure area and the second exposure area, and is composed of a first stitching exposure area close to the first exposure area and a second stitching exposure area close to the second exposure area, wherein the stitching exposure area is in contact with the first exposure area and the second exposure area at the same time. The substrate may be undoped single crystal silicon, single crystal silicon doped with impurities, silicon on insulator (SOI), stacked silicon on insulator (SSOI), stacked silicon germanium on insulator (S-SiGeOI), silicon germanium on insulator (SiGeOI) and germanium on insulator (GeOI), etc. The substrate may be a semiconductor substrate, a basic semiconductor layer on a support structure, a metal electrode or a semiconductor substrate having one or more layers, structures or regions formed thereon. As an example, in this embodiment, the constituent material of the substrate is selected from single crystal silicon.
[0078] S104, providing the photomask as described above.
[0079] S106, using the first sub-photomask in the photomask to expose and develop the first exposure area and the first stitching exposure area to form a photolithography pattern.
[0080] The first sub-photomask in the photomask is used to expose and develop the first exposure area and the first stitched exposure area to form a photolithography pattern. The projection of the first shielding portion in the first sub-photomask on the substrate overlaps with the second stitched exposure area to prevent light from irradiating the second stitched exposure area when the first sub-photomask is used for exposure and development.
[0081] S108, using a second sub-photomask in the photomask to expose and develop at least the second exposure area and the second stitching exposure area to form a photolithography pattern.
[0082] The second sub-photomask in the photomask is used to expose and develop at least the second exposure area and the second stitching exposure area to form a photolithography pattern. Exemplarily, in order to eliminate the alignment deviation of the photolithography machine, the second sub-photomask simultaneously exposes part of the first stitching exposure area.
[0083] In the above-mentioned exposure and development method, a first sub-photomask is used to expose and develop the first exposure area and the first stitched exposure area. The projection of the first shielding portion on the substrate coincides with the second stitched exposure area, so that when the first sub-photomask is used for exposure and development, light will not irradiate the second exposure area, that is, the second exposure area is only exposed by the second sub-photomask, thereby eliminating the influence of pattern diffraction and light refraction on the photolithography pattern formed in the second exposure area, and weakening the problem of pattern deformation of the photolithography pattern on the stitched exposure area.
[0084] It should be understood that although Figure 5The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 5 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.
[0085] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0086] The above-mentioned embodiments only express several implementation methods of the embodiments of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the embodiments of the present disclosure, and these all belong to the protection scope of the embodiments of the present disclosure.
Claims
1. A photomask, characterized in that: Used to form a photolithographic pattern on a photoresist film layer composed of positive photoresist on the surface of a substrate, comprising: a first sub-photomask and a second sub-photomask; The first sub-photomask comprises a first main pattern area and a first stitching area arranged side by side along the first direction, the first stitching area comprises a first shielding slave portion and a first sub-pattern area arranged side by side along the first direction, the first shielding slave portion is located at a side of the first sub-pattern area away from the first main pattern area, and the first shielding slave portion is used to shield light to prevent light from irradiating a first projection area of the first shielding slave portion on the photoresist film layer when the first sub-photomask is used for exposure and development; A first shielding main portion is formed in the first main graphic area and the first sub-graphic area, and a second shielding main portion is formed in the second sub-photomask. The first shielding main portion and the second shielding main portion are both used to shield light to form the photolithography pattern on the photoresist film layer. The second projection area of the second shielding main portion on the photoresist film layer covers the first projection area to form the photolithography pattern on the photoresist film layer corresponding to the first projection area.
2. The photomask according to claim 1, wherein: The first shielding slave portion and the first shielding master portion are made of the same material.
3. The photomask according to claim 1, wherein: The first shielding slave portion and the first shielding master portion are formed of different materials.
4. The photomask according to claim 1, wherein: The first shielding slave portion comprises: a first blocking layer, close to the first sub-pattern area, and made of the same material as the first shielding main portion; The second blocking layer is away from the first sub-pattern area and is made of a material different from that of the first shielding main portion.
5. The photomask according to claim 4, wherein: The transmittance of the first blocking layer to incident light is less than or equal to the transmittance of the second blocking layer to incident light.
6. The photomask according to claim 1, wherein: In the first direction, a first width of the first shielding portion is equal to a second width of the first sub-pattern area.
7. The photomask according to claim 1, wherein: The second sub-photomask comprises: a second main graphic area and a second stitching area arranged side by side in a first direction, the second stitching area comprises a second shielding slave portion and a second sub-graphic area arranged side by side along the first direction, the second main graphic area and the second sub-graphic area are provided with the second shielding main portion, the second shielding slave portion is located at a side of the second sub-graphic area away from the second main graphic area, and the second shielding slave portion is used to shield light to prevent light from irradiating a third projection area of the second shielding slave portion on the photoresist film layer when the second sub-photomask is used for exposure and development; There is no overlapping area between the third projection area and the first projection area.
8. The photomask according to claim 7, wherein: The first projection area and the third projection area are spaced apart, and a spacing distance between the first projection area and the third projection area is greater than or equal to an alignment deviation of a photolithography machine.
9. The photomask according to claim 7, wherein: The first shielding subordinate portion and the second shielding subordinate portion are made of at least partially the same material; and the shape of the first shielding subordinate portion and the shape of the second shielding subordinate portion are mirror images of each other.
10. A method of exposure and development, characterized in that: include: Providing a substrate, wherein a photoresist film layer composed of a positive photoresist is provided on the surface of the substrate, wherein the photoresist film layer comprises a first exposure area, a stitching exposure area and a second exposure area arranged side by side, wherein the stitching exposure area is located between the first exposure area and the second exposure area and is composed of a first stitching exposure area close to the first exposure area and a second stitching exposure area close to the second exposure area; Providing a photomask as described in any one of claims 1 to 9; Using a first sub-photomask in the photomask to expose and develop the first exposure area and the first stitching exposure area to form a photolithography pattern, a projection of the first shielding portion on the substrate coincides with the second stitching exposure area; The second sub-photomask in the photomask is used to expose and develop at least the second exposure area and the second stitching exposure area to form a photolithography pattern, and the projection of the second sub-photomask on the photoresist film layer covers the stitching exposure area and the second exposure area.