Optical proximity correction method, mask assembly and mask data processing device

Abstract

This invention provides an optical proximity correction method, a photomask assembly, and a photomask data processing apparatus. The method provides a target pattern, which includes a first pattern and a second pattern. The target pattern is then split into a first layout including the first pattern and a second layout including the second pattern. A first auxiliary pattern is disposed in a neighboring region of the first pattern, and a second auxiliary pattern is disposed in a neighboring region of the second pattern. The first layout including the first pattern and the first auxiliary pattern is output as a first photomask, and the second layout including the second pattern and the second auxiliary pattern is output as a second photomask. This invention improves the optical proximity effect caused by the influence of neighboring regions on the patterned area, reduces pattern defects generated when the first and second patterns are transferred to the wafer, and thus improves device reliability.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to an optical proximity correction method, a photomask assembly, and a photomask data processing apparatus. Background Technology

[0002] With the development of semiconductor technology, semiconductor devices are gradually becoming miniaturized and integrated. How to reduce the size of devices has become an important issue in the development of semiconductor technology. Currently, in semiconductor manufacturing processes, the layout pattern of integrated circuits is formed on a photomask. Then, the pattern on the photomask is transferred to the photoresist layer on the wafer using exposure and development steps. Subsequently, semiconductor devices are gradually formed by combining etching processes.

[0003] However, with the increasing integration of semiconductor devices and the shrinking of component sizes, the spacing between adjacent photoresist patterns has decreased, and the density of photoresist patterns is relatively high. The adjacent areas of the photoresist patterns are generally empty regions, which can easily lead to a loading effect when transferring the pattern from the photomask to the photoresist layer. During pattern transfer, the light beam diffracts as it passes through the photomask. When the patterned area and the empty area are adjacent, the amount of light passing through these two areas affects each other, producing an optical proximity effect (OPE). This results in deviations in the critical dimension (CD) or shape of the formed photoresist pattern. To address these issues, auxiliary patterns are typically placed in the photomask to reduce photoresist pattern defects. Therefore, how to set these auxiliary patterns has become a subject of further research. Summary of the Invention

[0004] The purpose of this invention is to provide an optical proximity correction method, a photomask assembly, and a photomask data processing device to improve the reliability of the device.

[0005] To achieve the above objectives, the present invention provides an optical proximity correction method, comprising:

[0006] A target pattern is provided, the target pattern including a first pattern and a second pattern;

[0007] The target pattern is divided into a first version including the first pattern and a second version including the second pattern;

[0008] A first auxiliary pattern is provided in the adjacent area of ​​the first pattern, and a second auxiliary pattern is provided in the adjacent area of ​​the second pattern, wherein the extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, and the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern.

[0009] The output includes a first pattern comprising the first pattern and the first auxiliary pattern as a first photomask, and the output includes a second pattern comprising the second pattern and the second auxiliary pattern as a second photomask;

[0010] Wherein, the projection position of the first pattern on the wafer intersects and overlaps with the projection position of the second pattern on the wafer, the planar projection of the first auxiliary pattern on the wafer intersects and overlaps with the projection position of the second auxiliary pattern on the wafer, and the intersecting and overlapping relationship of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersecting and overlapping relationship of the first pattern and the second pattern.

[0011] Optionally, the first pattern and the second pattern are located in the device region of the wafer, and the adjacent region includes a dummy pattern region, a boundary region, or a transition region located on the periphery of the device region.

[0012] Optional, also includes:

[0013] A third photomask is provided, the third photomask including a third pattern, the projection position of the third pattern on the wafer completely covering the first auxiliary pattern and the second auxiliary pattern but not covering the first pattern and the second pattern.

[0014] Optionally, at least one of the intersection angle, intersection position, overlap area, line width ratio, and spacing ratio of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersection angle, intersection position, overlap area, line width ratio, or spacing ratio of the first pattern and the second pattern.

[0015] Optionally, the first pattern includes a plurality of first sub-patterns, the second pattern includes a plurality of second sub-patterns, the first auxiliary pattern includes a plurality of first auxiliary sub-patterns, the second auxiliary pattern includes a plurality of second auxiliary sub-patterns, the plurality of first sub-patterns and the plurality of first auxiliary sub-patterns are arranged along a first direction, and the plurality of second sub-patterns and the plurality of second auxiliary sub-patterns are arranged along a second direction different from the first direction.

[0016] Optionally, the arrangement period of the first auxiliary sub-pattern and the second sub-auxiliary pattern is the same as or proportional to the arrangement period of the first sub-pattern and the second sub-pattern.

[0017] The present invention also provides a photomask assembly, comprising:

[0018] The first photomask includes a first pattern and a first auxiliary pattern;

[0019] The second photomask includes a second pattern and a second auxiliary pattern;

[0020] Wherein, the first auxiliary pattern is located in the adjacent area of ​​the first pattern, the second auxiliary pattern is located in the adjacent area of ​​the second pattern, the extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern, and the projection position of the first pattern on the wafer and the projection position of the second pattern on the wafer intersect and overlap, the planar projection of the first auxiliary pattern on the wafer and the projection position of the second auxiliary pattern on the wafer intersect and overlap, and the intersecting and overlapping relationship of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersecting and overlapping relationship of the first pattern and the second pattern.

[0021] Optionally, the first pattern and the second pattern are located in the device region of the wafer, and the adjacent region includes a dummy pattern region, a boundary region, or a transition region located on the periphery of the device region.

[0022] Optionally, a third photomask is also included, the third photomask comprising a third pattern, the projection position of the third pattern on the wafer completely covering the first auxiliary pattern and the second auxiliary pattern but not covering the first pattern and the second pattern.

[0023] Optionally, at least one of the intersection angle, intersection position, overlap area, line width ratio, and spacing ratio of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersection angle, intersection position, overlap area, line width ratio, or spacing ratio of the first pattern and the second pattern.

[0024] Optionally, the first pattern includes a plurality of first sub-patterns, the second pattern includes a plurality of second sub-patterns, the first auxiliary pattern includes a plurality of first auxiliary sub-patterns, the second auxiliary pattern includes a plurality of second auxiliary sub-patterns, the plurality of first sub-patterns and the plurality of first auxiliary sub-patterns are arranged along a first direction, and the plurality of second sub-patterns and the plurality of second auxiliary sub-patterns are arranged along a second direction different from the first direction.

[0025] Optionally, the arrangement period of the first auxiliary sub-pattern and the second sub-auxiliary pattern is the same as or proportional to the arrangement period of the first sub-pattern and the second sub-pattern.

[0026] The present invention also provides a photomask data processing apparatus for performing the optical proximity correction method as described above.

[0027] The present invention also provides a method for fabricating a semiconductor device using the optical proximity correction method described above.

[0028] In the optical proximity correction method provided by the present invention, a target pattern is provided, which includes a first pattern and a second pattern; the target pattern is split into a first layout including the first pattern and a second layout including the second pattern; a first auxiliary pattern is set in the adjacent region of the first pattern, and a second auxiliary pattern is set in the adjacent region of the second pattern, wherein the extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, and the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern; the first layout including the first pattern and the first auxiliary pattern is output as a first photomask, and the second layout including the second pattern and the second auxiliary pattern is output as a second photomask; wherein the projection position of the first pattern on the wafer and the projection position of the second pattern on the wafer overlap, the planar projection of the first auxiliary pattern on the wafer and the projection position of the second auxiliary pattern on the wafer overlap, and the overlap relationship between the first auxiliary pattern and the second auxiliary pattern corresponds to the overlap relationship between the first pattern and the second pattern. In this invention, the first pattern and the second pattern in the target pattern are separated, and a first auxiliary pattern is set in the adjacent area of ​​the first pattern and a second auxiliary pattern is set in the adjacent area of ​​the second pattern. That is, the auxiliary pattern is set in the empty area adjacent to the pattern area, which can effectively improve the optical proximity effect caused by the influence of the adjacent area on the pattern area, reduce the pattern defects generated when the first pattern and the second pattern are transferred to the wafer, and improve the reliability of the device. Attached Figure Description

[0029] Figure 1 This is a flowchart of an optical proximity correction method provided in an embodiment of the present invention.

[0030] Figure 2 The target pattern is provided in an optical proximity correction method according to an embodiment of the present invention.

[0031] Figure 3 This is a first layout of an optical proximity correction method provided in an embodiment of the present invention.

[0032] Figure 4 This is a second version of an optical proximity correction method provided in an embodiment of the present invention.

[0033] Figure 5 The first pattern is the first layout after setting the first auxiliary pattern in the optical proximity correction method provided in an embodiment of the present invention.

[0034] Figure 6 The second pattern is provided in an optical proximity correction method according to an embodiment of the present invention after setting a second auxiliary pattern.

[0035] Figure 7 and Figure 8 This is a schematic diagram showing the overlap of the first and second patterns in an optical proximity correction method provided in an embodiment of the present invention.

[0036] Figure 9 This is a schematic diagram showing the overlap of the first and second patterns in an optical proximity correction method provided in other embodiments of the present invention.

[0037] Figure 10 This is a schematic diagram of the third photomask in an optical proximity correction method provided in an embodiment of the present invention.

[0038] Figure 11 This is a schematic diagram showing the overlap of the third photomask with the first and second photomasks in an optical proximity correction method provided in an embodiment of the present invention.

[0039] The attached figures are labeled as follows:

[0040] 100 - Target pattern; 110 - First pattern; 110a - First sub-pattern; 120 - Second pattern; 120a - Second sub-pattern; 130 - Third pattern; 210 - First map; 220 - Second map; 230 - Third photomask; 310 - First auxiliary pattern; 310a - First auxiliary sub-pattern; 320 - Second auxiliary pattern; 320a - Second auxiliary sub-pattern. Detailed Implementation

[0041] To make the objectives, advantages, and features of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to facilitate and clarify the explanation of the embodiments of this invention. Furthermore, the structures shown in the drawings are often part of the actual structures. In particular, different figures may emphasize different aspects and may sometimes use different scales.

[0042] Please refer to Figure 1 This embodiment provides an optical proximity correction method, including:

[0043] Step S1: Provide a target pattern, which includes a first pattern and a second pattern;

[0044] Step S2: Divide the target pattern into a first pattern and a second pattern.

[0045] Step S3: Set a first auxiliary pattern in the adjacent area of ​​the first pattern and a second auxiliary pattern in the adjacent area of ​​the second pattern. The extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, and the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern.

[0046] Step S4: Output a first pattern including a first pattern and a first auxiliary pattern as a first photomask, and output a second pattern including a second pattern and a second auxiliary pattern as a second photomask.

[0047] The following is combined with Figures 2-11 The optical proximity correction method provided in this embodiment will be described in detail.

[0048] Please refer to Figure 2 Step S1: Provide a target pattern 100, which includes a first pattern 110 and a second pattern 120, located in the device region of the wafer. The first pattern 110 includes multiple first sub-patterns 110a, extending along a second direction D2 and arranged along a first direction D1. The second pattern 120 includes multiple second sub-patterns 120a, extending along the first direction D1 and arranged along the second direction D2. The first direction D1 and the second direction D2 intersect, either perpendicularly or at an angle less than 90 degrees. Furthermore, the first pattern 110 and the second pattern 120 are intersecting, meaning the projection positions of the first pattern 110 and the second pattern 120 on the wafer overlap, with a partial overlap area. The target pattern 100 includes at least one of the following: an active region pattern, a contact pattern, a capacitor pattern, a bit line pattern, or a word line pattern in a semiconductor structure. When transferring the target pattern 100 onto the wafer, an optical proximity effect occurs when the first pattern 110 and the second pattern 120 are adjacent to the dummy pattern area, boundary area or transition area on the outer periphery of the device area. This can easily lead to pattern defects after the first pattern 110 and the second pattern 120 are transferred, so optical proximity correction is required.

[0049] Please refer to Figure 3 and Figure 4 Step S2: Divide the target pattern 100 into a first pattern 210 including the first pattern 110 and a second pattern 220 including the second pattern 120, that is... Figure 2 The target pattern 100 is split into Figure 3 The first version 210, including the first pattern 110, and Figure 4 The second version 220 includes the second pattern 120. After splitting, the first version 210 and the first pattern 110 in the target pattern 100 are in the same position. For example, the spacing between two adjacent first sub-patterns 110a in the first version 210 and the target pattern 100 is the same. The second version 220 and the second pattern 120 in the target pattern 100 are in the same position. For example, the spacing between two adjacent second sub-patterns 120a in the second version 220 and the target pattern 100 is the same.

[0050] Execution step S3: Please refer to Figure 5A first auxiliary pattern 310 is provided in the adjacent area of ​​the first pattern 110. The adjacent area of ​​the first pattern 110 includes a dummy pattern area, boundary area, or transition area located on the outer periphery of the device area, and the adjacent area is an open area. The extension direction of the first auxiliary pattern 310 is the same as the extension direction of the first pattern 110 (both are the second direction D2). The first auxiliary pattern 310 includes a plurality of first auxiliary sub-patterns 310a. The plurality of first auxiliary sub-patterns 310a extend along the second direction D2 and are arranged along the first direction D1. The arrangement period of the first auxiliary sub-patterns 310a is the same as or proportional to the arrangement period of the first sub-patterns 110a. Figure 5 The diagram illustrates that the arrangement period of the first auxiliary sub-pattern 310a is the same as that of the first sub-pattern 110a.

[0051] Please refer to Figure 6 A second auxiliary pattern 320 is disposed in the adjacent area of ​​the second pattern 120. The adjacent area of ​​the second pattern 120 includes a dummy pattern area, boundary area, or transition area located on the outer periphery of the device area, and the adjacent area is an open area. The extension direction of the second auxiliary pattern 320 is the same as the extension direction of the second pattern 120 (both are the first direction D1). The second auxiliary pattern 320 includes a plurality of second auxiliary sub-patterns 320a, which extend along the first direction D1 and are arranged along the second direction D2. The arrangement period of the second auxiliary sub-patterns 320a is the same as or proportional to the arrangement period of the second sub-pattern 120a. Figure 6 The diagram illustrates that the arrangement period of the second auxiliary sub-pattern 320a is the same as that of the second sub-pattern 120a.

[0052] Please refer to Figure 7 , Figure 7 The diagram illustrates the overlapping of a first pattern and a second pattern. The projection positions of the first pattern 110 and the second pattern 120 on the wafer intersect and overlap. The planar projections of the first auxiliary pattern 310 and the second auxiliary pattern 320 on the wafer intersect and overlap, and the intersecting and overlapping relationship between the first auxiliary pattern 310 and the second auxiliary pattern 320 corresponds to the intersecting and overlapping relationship between the first pattern 110 and the second pattern 120. At least one of the intersection angle, intersection position, overlap area, linewidth ratio, and spacing ratio of the first auxiliary pattern 310 and the second auxiliary pattern 320 corresponds to the intersection angle, intersection position, overlap area, linewidth ratio, or spacing ratio of the first pattern 110 and the second pattern 120.

[0053] Please refer to Figure 8 , Figure 8The line width ratio and spacing ratio of the first auxiliary pattern 310 and the second auxiliary pattern 320 correspond to the line width ratio and spacing ratio of the first pattern 110 and the second pattern 120. Specifically, the line width of the first sub-pattern 110a is W1, the line width of the second sub-pattern 120a is W2, the line width of the first auxiliary sub-pattern 310a is W1', and the line width of the second auxiliary sub-pattern 320a is W2'. Therefore, the line width ratio (W1 / W2) of the first sub-pattern 110a and the second sub-pattern 120a is the same as the line width ratio (W1' / W2') of the first auxiliary sub-pattern 310a and the second auxiliary sub-pattern 320a. The spacing between adjacent first sub-patterns 110a is P1, the spacing between adjacent second sub-patterns 120a is P2, the spacing between adjacent first auxiliary sub-patterns 310a is P1', and the spacing between adjacent second auxiliary sub-patterns 320a is P2'. Therefore, the spacing ratio (P1 / P2) between adjacent first sub-patterns 110a and adjacent second sub-patterns 120a is the same as the spacing ratio (P1' / P2') between adjacent first auxiliary sub-patterns 310a and adjacent second auxiliary sub-patterns 320a.

[0054] In other embodiments, please refer to Figure 9 , Figure 9 The extension direction of the first auxiliary pattern 310 is different from that of the first pattern 110, and the extension direction of the second auxiliary pattern 320 is different from that of the second pattern 120. The extension direction of the first auxiliary pattern 310 is the fourth direction D4, and the extension direction of the second auxiliary pattern 320 is the third direction D3. The third direction D3 and the fourth direction D4 intersect; and the intersection angle of the first auxiliary pattern 310 and the second auxiliary pattern 320 is the same as the intersection angle of the first pattern 110 and the second pattern 120. Specifically, the intersection angle of the first pattern 110 and the second pattern 120 is the angle between the first direction D1 and the second direction D2, and the intersection angle of the first auxiliary pattern 310 and the second auxiliary pattern 320 is the angle between the third direction D3 and the fourth direction D4. The angle between the first direction D1 and the second direction D2 is the same as the angle between the third direction D3 and the fourth direction D4.

[0055] Execution step S4: Output a first pattern including a first pattern and a first auxiliary pattern as a first photomask, and output a second pattern including a second pattern and a second auxiliary pattern as a second photomask, that is, the first photomask includes the first pattern and the first auxiliary pattern, and the second photomask includes the second pattern and the second auxiliary pattern.

[0056] Further, please refer to Figure 10 and Figure 11It also includes providing a third photomask 230, the third photomask 230 including a third pattern 130, the projection position of the third pattern 130 on the wafer completely covering the projection positions of the first auxiliary pattern 310 and the second auxiliary pattern 320 on the wafer, such as... Figure 11 The third pattern 130 shown completely covers the first auxiliary pattern 310 and the second auxiliary pattern 320; and the projection position of the third pattern 130 on the wafer does not cover the projection positions of the first pattern 110 and the second pattern 120 on the wafer, as shown. Figure 11 The third pattern 130 shown will not cover the first pattern 110 and the second pattern 120.

[0057] In this embodiment, when the first pattern and the second pattern are adjacent to the dummy pattern area, boundary area, or transition area on the periphery of the device area, an optical proximity effect will occur during pattern transfer, which can easily lead to pattern defects after the first and second patterns are transferred. Therefore, by splitting the first and second patterns in the target pattern and setting a first auxiliary pattern in the adjacent area of ​​the first pattern and a second auxiliary pattern in the adjacent area of ​​the second pattern, that is, setting auxiliary patterns in the empty area adjacent to the pattern area, the optical proximity effect caused by the adjacent area can be effectively improved, and the pattern defects generated by the transfer of the first and second patterns to the wafer can be reduced, thereby improving the reliability of the device.

[0058] This embodiment also provides a photomask assembly, obtained using the aforementioned optical proximity correction method. The photomask assembly includes a first photomask and a second photomask. The first photomask includes a first pattern and a first auxiliary pattern, and the second photomask includes a second pattern and a second auxiliary pattern. The first auxiliary pattern is located in a neighboring region of the first pattern, and the second auxiliary pattern is located in a neighboring region of the second pattern. The extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, and the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern. The projection positions of the first pattern and the second pattern on the wafer intersect and overlap, and the planar projection of the first auxiliary pattern on the wafer intersects and overlaps with the projection positions of the second auxiliary pattern on the wafer. The intersecting and overlapping relationship between the first and second auxiliary patterns corresponds to the intersecting and overlapping relationship between the first and second patterns.

[0059] The first pattern and the second pattern are located in the device region of the wafer. The first pattern includes multiple first sub-patterns that extend along a second direction and are arranged along the first direction. The second pattern includes multiple second sub-patterns that extend along the first direction and are arranged along the second direction. The first and second directions intersect, either perpendicularly or at an angle of less than 90 degrees. Furthermore, the first and second patterns are interleaved, meaning the projection positions of the first and second patterns on the wafer overlap, and the first and second patterns have a partially overlapping area. The target pattern includes at least one of the following: an active region pattern, a contact pattern, a capacitor pattern, a bit line pattern, or a word line pattern in a semiconductor structure.

[0060] The adjacent area of ​​the first pattern includes a dummy pattern area, boundary area or transition area located on the periphery of the device area. The extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern (both are the second direction). The first auxiliary pattern includes multiple first auxiliary sub-patterns. The multiple first auxiliary sub-patterns extend along the second direction and are arranged along the first direction. The arrangement period of the first auxiliary sub-patterns is the same as or proportional to the arrangement period of the first sub-patterns.

[0061] The adjacent area of ​​the second pattern includes a dummy pattern area, boundary area, or transition area located on the periphery of the device area. The extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern (both are the first direction). The second auxiliary pattern includes multiple second auxiliary sub-patterns, which extend along the first direction and are arranged along the second direction. The arrangement period of the second auxiliary sub-patterns is the same as or proportional to the arrangement period of the second sub-patterns. At least one of the intersection angle, intersection position, overlap area, line width ratio, and spacing ratio of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersection angle, intersection position, overlap area, line width ratio, or spacing ratio of the first pattern and the second pattern.

[0062] Furthermore, the photomask assembly also includes a third photomask, which includes a third pattern. The projection position of the third pattern on the wafer completely covers the projection positions of the first auxiliary pattern and the second auxiliary pattern on the wafer, and the projection position of the third pattern on the wafer does not cover the projection positions of the first pattern and the second pattern on the wafer.

[0063] This embodiment also provides a photomask data processing apparatus, applied in computer software or a system, for executing the aforementioned optical proximity correction method. Specifically, it includes providing a target pattern, which includes a first pattern and a second pattern; splitting the target pattern into a first layout including the first pattern and a second layout including the second pattern; setting a first auxiliary pattern in a neighboring region of the first pattern and a second auxiliary pattern in a neighboring region of the second pattern, wherein the extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, and the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern; outputting the first layout including the first pattern and the first auxiliary pattern as a first photomask, and outputting the second layout including the second pattern and the second auxiliary pattern as a second photomask; wherein the projection position of the first pattern on the wafer overlaps with the projection position of the second pattern on the wafer, the planar projection of the first auxiliary pattern on the wafer overlaps with the projection position of the second auxiliary pattern on the wafer, and the overlap relationship between the first auxiliary pattern and the second auxiliary pattern corresponds to the overlap relationship between the first pattern and the second pattern.

[0064] Furthermore, it also includes providing a third photomask, the third photomask including a third pattern, the projection position of the third pattern on the wafer completely covering the projection positions of the first auxiliary pattern and the second auxiliary pattern on the wafer, and the projection position of the third pattern on the wafer does not cover the projection positions of the first pattern and the second pattern on the wafer.

[0065] This embodiment also provides a method for fabricating a semiconductor device using the aforementioned optical proximity correction method. Specifically, a first photomask and a second photomask are obtained using the aforementioned optical proximity correction method. The first photomask includes a first pattern and a first auxiliary pattern, and the second photomask includes a second pattern and a second auxiliary pattern. The first auxiliary pattern is located in a neighboring region of the first pattern, and the second auxiliary pattern is located in a neighboring region of the second pattern. The extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, and the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern. The projection positions of the first pattern and the second pattern on the wafer intersect and overlap, and the planar projection of the first auxiliary pattern on the wafer intersects and overlaps with the projection positions of the second auxiliary pattern on the wafer. The intersection and overlap relationship between the first auxiliary pattern and the second auxiliary pattern corresponds to the intersection and overlap relationship between the first pattern and the second pattern. Then, the patterns in the first and second photomasks are transferred to the photoresist layer on the wafer through exposure and development to form a photoresist pattern. The photoresist pattern is then transferred to the hard mask layer on the wafer to form a mask pattern, and then the photoresist pattern is removed. When the size of the first and second auxiliary patterns is small, they will not be transferred to the hard mask layer. If the first and second auxiliary patterns are not transferred to the hard mask layer, the mask pattern is then transferred to the target layer, where only the first and second patterns are on the target layer.

[0066] Furthermore, if the first and second auxiliary patterns are transferred to the hard mask layer, a third photomask is required. The third photomask includes a third pattern, the projection position of which on the wafer completely covers the projection positions of the first and second auxiliary patterns on the wafer, and the projection position of which on the wafer does not cover the projection positions of the first and second patterns. The pattern of the third photomask is then transferred to a photoresist layer on the wafer through exposure and development to form a photoresist pattern. The polarity of the photoresist layer exposed and developed using the third photomask (e.g., negative photoresist) is opposite to the polarity of the photoresist layer exposed and developed using the first and second photomasks (e.g., positive photoresist). The photoresist pattern exposes the first and second auxiliary patterns transferred to the hard mask layer. Then, the first and second auxiliary patterns are etched away, and the photoresist pattern is removed. Finally, the pattern of the hard mask layer is transferred to the target layer, where only the first and second patterns are present.

[0067] In summary, the optical proximity correction method provided by this invention includes a target pattern comprising a first pattern and a second pattern; the target pattern is divided into a first layout comprising the first pattern and a second layout comprising the second pattern; a first auxiliary pattern is disposed in a neighboring region of the first pattern, and a second auxiliary pattern is disposed in a neighboring region of the second pattern, wherein the extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, and the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern; the first layout comprising the first pattern and the first auxiliary pattern is output as a first photomask, and the second layout comprising the second pattern and the second auxiliary pattern is output as a second photomask; wherein the projection position of the first pattern on the wafer overlaps with the projection position of the second pattern on the wafer, the planar projection of the first auxiliary pattern on the wafer overlaps with the projection position of the second auxiliary pattern on the wafer, and the overlap relationship between the first auxiliary pattern and the second auxiliary pattern corresponds to the overlap relationship between the first pattern and the second pattern. In this invention, the first pattern and the second pattern in the target pattern are separated, and a first auxiliary pattern is set in the adjacent area of ​​the first pattern and a second auxiliary pattern is set in the adjacent area of ​​the second pattern. That is, the auxiliary pattern is set in the empty area adjacent to the pattern area, which can effectively improve the optical proximity effect caused by the influence of the adjacent area on the pattern area, reduce the pattern defects generated when the first pattern and the second pattern are transferred to the wafer, and improve the reliability of the device.

[0068] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in the present invention without departing from the scope of the present invention shall be deemed to have remained within the protection scope of the present invention.

Claims

1. An optical proximity correction method, characterized in that, include: A target pattern is provided, the target pattern including a first pattern and a second pattern; The target pattern is divided into a first version including the first pattern and a second version including the second pattern; A first auxiliary pattern is provided in the adjacent area of ​​the first pattern, and a second auxiliary pattern is provided in the adjacent area of ​​the second pattern, wherein the extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, and the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern. The output includes a first pattern comprising the first pattern and the first auxiliary pattern as a first photomask, and the output includes a second pattern comprising the second pattern and the second auxiliary pattern as a second photomask; Wherein, the projection position of the first pattern on the wafer intersects and overlaps with the projection position of the second pattern on the wafer, the planar projection of the first auxiliary pattern on the wafer intersects and overlaps with the projection position of the second auxiliary pattern on the wafer, and the intersecting and overlapping relationship of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersecting and overlapping relationship of the first pattern and the second pattern.

2. The optical proximity correction method as described in claim 1, characterized in that, The first pattern and the second pattern are located in the device area of ​​the wafer, and the adjacent area includes a dummy pattern area, a boundary area or a transition area located on the outer periphery of the device area.

3. The optical proximity correction method as described in claim 1, characterized in that, Also includes: A third photomask is provided, the third photomask including a third pattern, the projection position of the third pattern on the wafer completely covering the first auxiliary pattern and the second auxiliary pattern but not covering the first pattern and the second pattern.

4. The optical proximity correction method as described in claim 1, characterized in that, At least one of the following: the intersection angle, intersection position, overlap area, line width ratio, and spacing ratio of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersection angle, intersection position, overlap area, line width ratio, or spacing ratio of the first pattern and the second pattern.

5. The optical proximity correction method as described in claim 1, characterized in that, The first pattern includes a plurality of first sub-patterns, the second pattern includes a plurality of second sub-patterns, the first auxiliary pattern includes a plurality of first auxiliary sub-patterns, the second auxiliary pattern includes a plurality of second auxiliary sub-patterns, the plurality of first sub-patterns and the plurality of first auxiliary sub-patterns are arranged along a first direction, and the plurality of second sub-patterns and the plurality of second auxiliary sub-patterns are arranged along a second direction different from the first direction.

6. The optical proximity correction method as described in claim 5, characterized in that, The arrangement period of the first auxiliary sub-pattern and the second sub-auxiliary pattern is the same as or proportional to the arrangement period of the first sub-pattern and the second sub-pattern.

7. A photomask assembly, characterized in that, include: The first photomask includes a first pattern and a first auxiliary pattern; The second photomask includes a second pattern and a second auxiliary pattern; Wherein, the first auxiliary pattern is located in the adjacent area of ​​the first pattern, the second auxiliary pattern is located in the adjacent area of ​​the second pattern, the extension direction of the first auxiliary pattern is the same as the extension direction of the first pattern, the extension direction of the second auxiliary pattern is the same as the extension direction of the second pattern, and the projection position of the first pattern on the wafer and the projection position of the second pattern on the wafer intersect and overlap, the planar projection of the first auxiliary pattern on the wafer and the projection position of the second auxiliary pattern on the wafer intersect and overlap, and the intersecting and overlapping relationship of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersecting and overlapping relationship of the first pattern and the second pattern.

8. The photomask assembly as described in claim 7, characterized in that, The first pattern and the second pattern are located in the device area of ​​the wafer, and the adjacent area includes a dummy pattern area, a boundary area or a transition area located on the outer periphery of the device area.

9. The photomask assembly as described in claim 7, characterized in that, It also includes a third photomask, which includes a third pattern, the projection of which on the wafer completely covers the first auxiliary pattern and the second auxiliary pattern but does not cover the first pattern and the second pattern.

10. The photomask assembly as described in claim 7, characterized in that, At least one of the following: the intersection angle, intersection position, overlap area, line width ratio, and spacing ratio of the first auxiliary pattern and the second auxiliary pattern corresponds to the intersection angle, intersection position, overlap area, line width ratio, or spacing ratio of the first pattern and the second pattern.

11. The photomask assembly as described in claim 7, characterized in that, The first pattern includes a plurality of first sub-patterns, the second pattern includes a plurality of second sub-patterns, the first auxiliary pattern includes a plurality of first auxiliary sub-patterns, the second auxiliary pattern includes a plurality of second auxiliary sub-patterns, the plurality of first sub-patterns and the plurality of first auxiliary sub-patterns are arranged along a first direction, and the plurality of second sub-patterns and the plurality of second auxiliary sub-patterns are arranged along a second direction different from the first direction.

12. The photomask assembly as described in claim 11, characterized in that, The arrangement period of the first auxiliary sub-pattern and the second sub-auxiliary pattern is the same as or proportional to the arrangement period of the first sub-pattern and the second sub-pattern.

13. A photomask data processing device, characterized in that, Perform the optical proximity correction method as described in claim 1.

14. A method for fabricating a semiconductor device, characterized in that, It is fabricated using the optical proximity correction method as described in claim 1.

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