Metal layer layout processing method

Abstract

The application provides a metal layer layout processing method, and belongs to the technical field of semiconductor manufacturing. The processing method comprises the following steps: obtaining a metal layer layout and a via layer layout corresponding to the metal layer layout; splitting the metal layer layout into at least a first sub-layout and a second sub-layout according to a first preset rule; determining a first hotspot pattern in the first sub-layout according to a second preset rule; determining a first background pattern and a second background pattern adjacent to the first hotspot pattern; obtaining a first distance between a via pattern and the first background pattern, and obtaining a second distance between the first hotspot pattern and the second background pattern; and adjusting the first hotspot pattern to the second sub-layout when the difference between the first distance and a preset surrounding distance is less than the second distance. The method can improve the coverage of the metal layer on the adjacent via layer.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a method for processing metal layer layout. Background Technology

[0002] As semiconductor process nodes continue to shrink, the density and complexity of metal layers and via structures have increased significantly, placing higher demands on the imaging accuracy of photolithography. Traditional single-pass photolithography processes, limited by the Rayleigh criterion, struggle to achieve high-fidelity transfer of high-density metal lines and via patterns on the layout in advanced node processes.

[0003] The industry uses dual patterning (DPT) technology to split the mask into at least two independent mask patterns and perform exposure, development, and etching processes on them separately. This indirectly relaxes the limitations of lithography resolution and effectively alleviates the problem of insufficient lithography resolution in advanced process technologies.

[0004] However, current dual patterning technology, after splitting the metal layer layout based on design rules (DRC), is still easily constrained by the tightly arranged patterns in the sub-layouts. It cannot reserve sufficient process windows for aligning via patterns in subsequent layout processing and exposure. As a result, during manufacturing, the via edges are easily exposed due to alignment or etching deviations, which can lead to increased circuit contact resistance, short circuits, and open circuit risks.

[0005] Therefore, a metal layer layout processing method needs to be designed to improve the above problems. Summary of the Invention

[0006] This invention provides a method for processing metal layer patterns to improve upon the shortcomings of existing pattern splitting methods, which cannot reserve a process window for aligning via coverage in the metal layer pattern of the split sub-pattern. This results in insufficient coverage of vias by the metal layer in the exposure circuit of the corrected sub-pattern, leading to risks such as increased circuit contact resistance, short circuits, and open circuits.

[0007] In a first aspect, the present invention provides a method for processing a metal layer layout, the method comprising: Obtain the metal layer layout and the corresponding via layer layout; According to a first preset rule, the metal layer layout is divided into at least two sub-layouts, the at least two sub-layouts including a first sub-layout and a second sub-layout; A first hot spot pattern is determined in the first sub-layout according to a second preset rule; the first hot spot pattern surrounds the via pattern of the via layer layout, and the shortest distance between the first hot spot pattern and the via pattern is less than the preset enclosure distance of the via pattern; In the first sub-plot, a first background pattern adjacent to the first hotspot pattern is determined, and in the second sub-plot, a second background pattern adjacent to the first hotspot pattern is determined; wherein, the distance between the first background pattern and the first hotspot pattern is less than or equal to a first preset distance, and the distance between the second background pattern and the first hotspot pattern is less than or equal to a second preset distance; Obtain the shortest first distance between the through-hole pattern and the first background pattern, and obtain the shortest second distance between the first hotspot pattern and the second background pattern; when the difference between the first distance and the preset enclosing distance is less than the second distance, adjust the first hotspot pattern to the second sub-pattern.

[0008] In one example of the present invention, the processing method further includes: A second hot spot pattern is determined in the second sub-layout according to a second preset rule; the second hot spot pattern surrounds the via pattern of the via layer layout, and the shortest distance between the second hot spot pattern and the via pattern is less than the preset enclosure distance of the via pattern; In the second sub-map, a third background pattern adjacent to the second hotspot pattern is determined, and in the first sub-map, a fourth background pattern adjacent to the second hotspot pattern is determined; wherein, the distance between the third background pattern and the second hotspot pattern is less than or equal to a first preset distance, and the distance between the fourth background pattern and the second hotspot pattern is less than or equal to a second preset distance; Obtain the shortest third distance between the through-hole pattern and the third background pattern, and obtain the shortest fourth distance between the second hotspot pattern and the fourth background pattern; when the difference between the third distance and the preset enclosing distance is less than the fourth distance, adjust the second hotspot pattern to the first sub-pattern.

[0009] In one example of the present invention, the step of splitting the metal layer layout into at least two sub-layouts according to a first preset rule includes: determining a first metal pattern and a second metal pattern whose adjacent spacing is less than or equal to a preset splitting distance, and setting the first metal pattern in the first sub-layout and the second metal pattern in the second sub-layout.

[0010] In one example of the present invention, the step of splitting the metal layer layout into at least two sub-layouts according to a first preset rule further includes: Identify the unsplit third metal pattern in the metal layer layout; the third metal pattern is located between the first metal pattern and the second metal pattern, and the distance between the third metal pattern and its surrounding adjacent metal patterns is greater than a preset split distance; When the shortest distance between the third metal pattern and the second metal pattern is less than the shortest distance between the third metal pattern and the first metal pattern, the third metal pattern is set in the first sub-pattern. When the shortest distance between the third metal pattern and the first metal pattern is less than the shortest distance between the third metal pattern and the second metal pattern, the third metal pattern is set in the second sub-pattern.

[0011] In one example of the present invention, the first preset distance and the second preset distance are less than the preset split distance.

[0012] In one example of the present invention, the processing method further includes performing optical proximity effect correction processing on the adjusted first sub-pattern and the second sub-pattern respectively; the optical proximity effect correction processing includes: expanding the outer edge of the first hot spot pattern that has the shortest distance to the through hole pattern, and expanding the outer edge of the second hot spot pattern that has the shortest distance to the through hole pattern.

[0013] The metal layer layout processing method provided by this invention identifies hotspot patterns with insufficient via coverage in the metal layer layout after splitting it according to preset rules. It determines the reserved correction space between the hotspot pattern and the surrounding background pattern within the same sub-layout, and confirms whether this correction space is lower than the distance between the hotspot pattern and the background pattern of different surrounding sub-layouts. If it is determined that the reserved correction space is insufficient to suppress the expansion correction of the hotspot pattern's outer edge, the hotspot pattern is transferred from its original sub-layout to another sub-layout. In the newly divided sub-layout, the hotspot pattern can expand outwards during the correction process to cover the insufficient via coverage, thereby ensuring that the split sub-layout pattern has sufficient process windows to offset process deviations in photolithography and etching. This results in sufficient coverage of the metal layer over adjacent via layers after exposure, reducing the possibility of via edge exposure due to alignment errors or etching deviations during manufacturing, significantly improving the performance and production yield of integrated circuits. Attached Figure Description

[0014] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other embodiments based on these drawings without inventive effort.

[0015] In the attached diagram: Figure 1 This is a schematic flowchart of a metal layer layout processing method according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the unsplit metal layer layout and the corresponding via layer layout in one embodiment of the present invention; Figure 3 This is a schematic diagram of step S2 of the present invention, which splits the layout into two sub-layouts according to a first preset rule; Figure 4 This is another schematic diagram of step S2 in one embodiment of the present invention, which splits the two sub-layouts according to a first preset rule; Figure 5 This is a schematic diagram of the first hotspot pattern or the second hotspot pattern determined in step S3 of an embodiment of the present invention; Figure 6 This is a schematic diagram of step S4 in an embodiment of the present invention, which determines the first distance and the second distance around the first hotspot pattern in the first sub-plot. Figure 7 This is a schematic diagram of two sub-patterns after the first hotspot pattern is re-divided in step S5 of an embodiment of the present invention; Figure 8 This is a schematic diagram of step S4 in another embodiment of the present invention, which determines the third and fourth distances around the second hotspot pattern in the second sub-plot; Figure 9 This is a schematic diagram of two sub-patterns after the second hotspot pattern is re-divided in step S5 of an embodiment of the present invention; Figure 10 This is a schematic diagram of the correction process for splitting sub-layouts based on the DRC method; Figure 11 This is a schematic diagram illustrating the process of splitting and modifying the sub-layouts according to the method of this application; The attached figures are labeled as follows: 10. First sub-pattern; 20. Second sub-pattern; 30. Through-hole pattern; 31. Relative outer edge; 40. First metal pattern; 50. Second metal pattern; 60. Third metal pattern; 100, First hotspot pattern; 200, First background pattern; 300, Second background pattern; 400, Second hotspot pattern; 500, Third background pattern; 600, Fourth background pattern; L1, Outer edge of hotspot; L2, Parallel outer edge; E, Preset enclosing distance; D1, First distance; D2, Second distance; D3, Third distance; D4, Fourth distance. Detailed Implementation

[0016] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features can be combined with each other. It should also be understood that the terminology used in the embodiments of the present invention is for describing specific implementation schemes and not for limiting the scope of protection of the present invention. Test methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or according to the conditions recommended by the respective manufacturers.

[0017] It should be noted that the terms such as "upper", "lower", "left", "right", "middle" and "one" used in this specification are only for clarity of description and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered as part of the scope of the invention.

[0018] Currently, the industry utilizes dual patterning (DPT) technology to split the lithography pattern into at least two independent sub-patterns, and expands the limitations of lithography processes on pattern resolution by performing independent exposure, development, and etching processes on the split sub-patterns.

[0019] However, the applicant's research found that the current dual patterning technology only mechanically splits the metal layer layout based on design rules (DRC), ignoring the alignment and compatibility between the metal pattern and the via pattern. It does not dynamically optimize the distribution of the metal layer pattern during the splitting stage, and cannot reserve sufficient process windows in the metal pattern of the split sub-layout to offset the process deviations in the photolithography and etching stages. As a result, during the manufacturing process, the via edges may be exposed due to alignment errors or etching deviations, which may lead to increased circuit contact resistance, short circuits, and open circuit risks.

[0020] To improve the aforementioned technical deficiencies, in the first aspect, such as Figure 1 As shown, the present invention provides a method for processing a metal layer layout, the method comprising the following steps: Step S1: Obtain the metal layer layout and the corresponding via layer layout.

[0021] like Figure 2 As shown, in step S1, a metal layer layout and a corresponding via layer layout are provided and input. The via layer layout includes the via pattern 30 to be exposed. The via pattern 30 is located on the upper or lower layer of the metal layer image to be exposed in the metal layer layout.

[0022] Next, step S2 is performed: the metal layer layout is divided into at least two sub-layouts according to the first preset rule, and the at least two sub-layouts include the first sub-layout. Figure 10 And the second sub-page 20. As in one example, the first sub-page split in step S2. Figure 10 It is adjacent to the second sub-territory 20.

[0023] In step S2, the metal patterns in the metal layer layout can be split based on the Design Rules (DRC). First, patterns with a spacing smaller than the preset split distance are split into two sub-layouts. Then, for patterns with a spacing greater than the preset split distance from their surrounding patterns, the unsplit pattern is split into two sub-layouts with the surrounding pattern with the smallest spacing, according to the principle that the smaller the spacing, the higher the priority for splitting. This completes the splitting of all patterns in the metal layer layout.

[0024] Specifically, such as Figure 3 As shown, in some embodiments, step S2 includes the following steps: S21. Determine adjacent metal patterns with a spacing smaller than a preset split distance from the metal layer layout, and set the selected adjacent metal patterns respectively in the first sub-layout. Figure 10 In the second sub-territory 20.

[0025] like Figure 3 and Figure 4 As shown, in the metal layer layout, a second metal pattern 50 and a third metal pattern 60 that are adjacent to each other and have a spacing smaller than a preset split distance are selected, and the second metal pattern 50 is set in the first sub-layout. Figure 10 In the middle, the third metal pattern 60 is set in the second sub-page 20; wherein the spacing between the second metal pattern 50 and the third metal pattern 60 is less than the preset split distance.

[0026] S22. Determine the location of the first sub-page in the metal layer layout. Figure 10 The first metal pattern 40 between the second sub-pattern 20 and the first metal pattern 40, wherein the shortest distance between the first metal pattern 40 and its surrounding adjacent metal patterns is greater than a preset split distance, such as the first metal pattern 40 and the first sub-pattern Figure 10 Since the shortest distance between the first metal pattern 40 and the second sub-pattern 20 is greater than the preset splitting distance, the first metal pattern 40 has not yet been split into any sub-pattern in step S21.

[0027] For example Figure 3 and Figure 4 As shown, the first metal pattern 40 belongs to the first sub-pattern Figure 10 The second metal pattern 50 and the third metal pattern 60 belonging to the second sub-pattern 20 are adjacent. The distance between the first metal pattern 40 and the second metal pattern 50 is greater than the preset split distance, and the distance between the first metal pattern 40 and the third metal pattern 60 is greater than the preset split distance.

[0028] S23. When the shortest distance between the first metal pattern 40 and the second sub-pattern 20 is less than the distance between the first metal pattern 40 and the first sub-pattern... Figure 10 When the minimum spacing between them is reached, the first metal pattern 40 is set in the first sub-plate. Figure 10 middle.

[0029] like Figure 3 In one example, when the distance between the first metal pattern 40 and the nearest third metal pattern 60 is less than the distance between the first metal pattern 40 and the nearest second metal pattern 50, the first metal pattern 40 is assigned to the first sub-pattern to which the second metal pattern 50 belongs. Figure 10 middle.

[0030] S24, when the first metal pattern 40 and the first sub-plate Figure 10 When the shortest distance between them is less than the shortest distance between the first metal pattern 40 and the second sub-pattern 20, the first metal pattern 40 is placed in the second sub-pattern 20.

[0031] like Figure 4 In one example, when the distance between the first metal pattern 40 and the nearest second metal pattern 50 is less than the distance between the first metal pattern 40 and the nearest third metal pattern 60, the first metal pattern 40 is assigned to the second sub-pattern 20 to which the third metal pattern 60 belongs.

[0032] Next, step S3 is executed to determine the first sub-version according to the second preset rule. Figure 10 The most popular pattern in China is number 100.

[0033] In step S3, in the first sub-version Figure 10 The metal pattern (e.g., the metal pattern surrounding the upper or lower through-hole pattern 30) is identified. Figures 3 to 6 The first metal pattern 40 in the image is analyzed based on a second preset rule to determine whether the metal pattern has reserved sufficient enclosing space for the through hole pattern 30. If the metal pattern has not reserved sufficient enclosing space for the through hole pattern 30, then the metal pattern is defined as the first hot spot pattern 100.

[0034] Specifically, in step S3, in the first sub-version Figure 10 In the case of a metal pattern surrounding a through-hole pattern 30, if the shortest distance between the metal pattern and the through-hole pattern 30 is less than the preset surrounding distance E of the through-hole pattern 30, then the edge of the through-hole pattern 30 is at risk of being exposed outside the metal pattern after exposure, and thus the metal pattern can be identified as the first hot spot pattern 100.

[0035] like Figure 5 and Figure 6As shown, in one embodiment, step S3 includes the following steps: S31, From the first sub-version Figure 10 The first metal pattern 40 surrounding the through-hole pattern 30 is screened in the middle; S32. When the shortest distance between the outer edge of the first metal pattern 40 and the through-hole pattern 30 is less than the preset enclosure distance E, the outer edge is taken as the hot spot outer edge L1, and the first metal pattern 40 is determined as the first sub-pattern. Figure 10 The first hotspot pattern in the image is 100.

[0036] In step S32, after the via pattern 30 is exposed, the exposed image of the via pattern 30 is easily exposed outside the hot spot L1 of the first metal pattern 40, which makes the metal layer of the first metal pattern 40 insufficient to cover the via layer, thereby easily causing the contact resistance of the layout process circuit to increase or even short circuit or open circuit problems.

[0037] In some embodiments, the processing method is applied to the first sub-version. Figure 10 In the first hotspot pattern 100, execute step S4: in the first sub-page Figure 10 In the first sub-layout 20, a first background pattern 200 adjacent to the first hotspot pattern 100 is determined, and in the second sub-layout 20, a second background pattern 300 adjacent to the first hotspot pattern 100 is determined.

[0038] like Figure 6 As shown, in step S4, in the first sub-version Figure 10 A first background pattern 200 is determined around the first hotspot pattern 100. The distance between the first background pattern 200 and the first hotspot pattern 100 is less than a first preset distance to ensure that the first background pattern 200 is adjacent to the first hotspot pattern 100. For example, if the determined first background pattern 200 is the first sub-pattern... Figure 10 The pattern closest to the first hotspot pattern 100 is selected. In the second sub-layout 20, a second background pattern 300 is determined surrounding the first hotspot pattern 100. The distance between the second background pattern 300 and the first hotspot pattern 100 is less than a second preset distance to ensure that the second background pattern 300 is adjacent to the first hotspot pattern 100, i.e., the determined second background pattern 300 is the pattern in the second sub-layout 20 closest to the first hotspot pattern 100. Furthermore, in some embodiments, the first preset distance and the second preset distance are less than a preset split distance. Next, step S5 is executed: the shortest first distance D1 between the through-hole pattern 30 and the first background pattern 200 is obtained, and the shortest second distance D2 between the first hotspot pattern 100 and the second background pattern 300 is obtained; when the difference between the first distance D1 and the preset enclosing distance E is less than the second distance D2, the first hotspot pattern 100 is moved from its original first sub-pattern. Figure 10 Adjusted to the second sub-map 20.

[0039] like Figure 6 As shown, in step S5, the shortest first distance D1 between the through-hole pattern 30 and the first background pattern 200 is obtained, and the shortest second distance D2 between the first hotspot pattern 100 and the second background pattern 300 is obtained. Obtaining the first distance D1 and the second distance D2 in step S5 allows for the confirmation of the first sub-pattern in subsequent comparison steps. Figure 10 Whether a sufficient process window is reserved between the first hot spot pattern 100 and the first background pattern 200 so that the outer edge L1 of the hot spot can be expanded outward during the sub-pattern correction process, thereby eliminating the defect that the first hot spot pattern 100 does not cover the surrounding through hole pattern 30.

[0040] like Figure 6 As shown, in one embodiment, when there is a hot spot outer edge L1 in the first hot spot pattern 100 and the hot spot outer edge L1 is directly opposite the first background pattern 200, the relative outer edge 31 in the through hole pattern 30 that is close to and parallel to the hot spot outer edge L1 is determined, and the shortest distance between the relative outer edge 31 and the first background pattern 200 is taken as the first distance D1; at the same time, the parallel outer edge L2 in the first hot spot pattern 100 that is parallel to the hot spot outer edge L1 is determined, and the shortest distance between the parallel outer edge L2 and the second background pattern 300 is taken as the second distance D2.

[0041] In another embodiment, when there are at least two hot spot outer edges L1 in the first hot spot pattern 100 that are directly opposite the first background pattern 200, the relative outer edges 31 in the through hole pattern 30 that are opposite to each hot spot outer edge L1 are determined, the shortest distance between each relative outer edge 31 and the first background pattern 200 is obtained, and the minimum value among them is taken as the first distance D1; at the same time, the shortest distance between the first hot spot pattern 100 and the second background pattern 300 is taken as the second distance D2.

[0042] like Figure 7 As shown, in step S5, when the difference between the first distance D1 and the preset enclosing distance E is less than the second distance D2, the first sub-page is confirmed. Figure 10 Insufficient process window space is reserved between the first hot spot pattern 100 and the first background pattern 200. In this case, if subsequent layout correction processing is performed using the current sub-layout from step S2, the outward expansion of the hot spot edge L1 in the first hot spot pattern 100 will be suppressed, resulting in insufficient coverage of the via by the metal layer after exposure. Therefore, in step S5, when it is determined that the difference between the first distance D1 and the preset enclosure distance E is less than the second distance D2, the first hot spot pattern 100 is moved from the first sub-layout... Figure 10 It was assigned to the second sub-region 20.

[0043] like Figure 8 and Figure 9 As shown, in some embodiments, the processing method further includes steps related to hotspot pattern identification and re-division of the second sub-landscape 20. Specifically, this includes: Step S3: Determine the second hotspot pattern 400 in the second sub-pattern 20 according to the second preset rule. Specifically, identify the metal pattern (such as...) surrounding the upper or lower through-hole pattern 30 in the second sub-pattern 20. Figures 3 to 6 If the shortest distance between the metal pattern 40 and the through hole pattern 30 is less than the preset enclosure distance E of the through hole pattern 30, then the metal pattern does not reserve enough enclosure margin space to cover the through hole pattern 30. The through hole pattern 30 is at risk of being exposed outside the metal pattern at the edge after exposure. Thus, the metal pattern can be identified as the second hot spot pattern 400 in the second sub-pattern 20.

[0044] like Figure 5 and Figure 8 As shown, in one embodiment, step S3 includes the following steps: selecting a first metal pattern 40 surrounding the through hole pattern 30 from the second sub-layout 20; when there is a shortest distance between the outer edge of the first metal pattern 40 and the through hole pattern 30 that is less than a preset surrounding distance E, then the outer edge is taken as the hot spot outer edge L1, and the first metal pattern 40 is determined to be the first hot spot pattern 100 in the second sub-layout 20.

[0045] Step S4: In the second sub-page 20, determine the third background pattern 500 adjacent to the second hotspot pattern 400, and in the first sub-page... Figure 10 The fourth background pattern 600 adjacent to the second hotspot pattern 400 is determined. Specifically, the distance between the third background pattern 500 and the second hotspot pattern 400 is less than or equal to a first preset distance, and the distance between the fourth background pattern 600 and the second hotspot pattern 400 is less than or equal to a second preset distance. Step S4 determines the third background pattern 500 closest to the second hotspot pattern 400 in the second sub-page 20 and the first sub-page based on the above rules. Figure 10 The fourth background pattern 600 is closest to the first hotspot pattern 100.

[0046] Step S5: Obtain the shortest third distance D3 between the through-hole pattern 30 and the third background pattern 500, and obtain the shortest fourth distance D4 between the second hotspot pattern 400 and the fourth background pattern 600; when the difference between the third distance D3 and the preset enclosing distance E is less than the fourth distance D4, adjust the second hotspot pattern 400 from the second sub-pattern 20 to the first sub-pattern. Figure 10 middle.

[0047] like Figure 6As shown, in step S5, the shortest third distance D3 between the through-hole pattern 30 and the third background pattern 500 is obtained, and the shortest fourth distance D4 between the second hot spot pattern 400 and the fourth background pattern 600 is obtained. Obtaining the third distance D3 and the fourth distance D4 in step S5 can confirm in the subsequent comparison step whether a sufficient process window is reserved between the second hot spot pattern 400 and the third background pattern 500 in the second sub-pattern 20, so that the outer edge L1 of the hot spot can be expanded outward during the sub-pattern correction process, thereby eliminating the defect of insufficient coverage of the second hot spot pattern 400 surrounding the through-hole pattern 30.

[0048] like Figure 8 As shown, in one embodiment, when there is a hot spot outer edge L1 in the second hot spot pattern 400 and the hot spot outer edge L1 is directly opposite the third background pattern 500, the relative outer edge 31 in the through hole pattern 30 that is close to and parallel to the hot spot outer edge L1 is determined, and the shortest distance between the relative outer edge 31 and the third background pattern 500 is taken as the first distance D1; at the same time, the parallel outer edge L2 in the second hot spot pattern 400 that is parallel to the hot spot outer edge L1 is determined, and the shortest distance between the parallel outer edge L2 and the fourth background pattern 600 is taken as the fourth distance D4.

[0049] In another embodiment, when there are at least two hot spot outer edges L1 in the second hot spot pattern 400 that are directly opposite the third background pattern 500, the relative outer edges 31 in the through hole pattern 30 that are opposite to each hot spot outer edge L1 are determined, the shortest distance between each relative outer edge 31 and the third background pattern 500 is obtained, and the minimum value among them is taken as the first distance D1; at the same time, the shortest distance between the second hot spot pattern 400 and the fourth background pattern 600 is taken as the fourth distance D4.

[0050] like Figure 9 As shown, in step S5, when the difference between the third distance D3 and the preset enclosure distance E is less than the fourth distance D4, it is confirmed that insufficient process window space is reserved between the second hot spot pattern 400 and the third background pattern 500 in the second sub-layout 20. In this case, if subsequent layout correction processing is performed based on the current sub-layout division in step S2, the outward expansion of the hot spot outer edge L1 in the second hot spot pattern 400 will be suppressed, resulting in insufficient coverage of the via by the metal layer after exposure. Therefore, in step S5, when it is determined that the difference between the third distance D3 and the preset enclosure distance E is less than the fourth distance D4, the second hot spot pattern 400 is divided from the second sub-layout 20 to the first sub-layout. Figure 10 middle.

[0051] Furthermore, the processing method of this application also includes step S6, which involves performing optical proximity correction processing on the at least two sub-patterns re-divided in step S5 to obtain corrected patterns of at least two sub-patterns. The optical proximity correction in this step can be rule-based optical proximity correction (RBOPC) or model-based optical proximity correction (MBOPC), and the correction rule used can be any suitable rule. like Figure 11 As shown, in some embodiments, in step S6, the optical proximity effect correction process includes processing the first sub-plate. Figure 10 The first hot spot pattern 100 in the first sub-pattern 20 undergoes edge expansion processing, as does the second hot spot pattern 400 in the second sub-pattern 20. Specifically, the hot spot pattern that was originally assigned to another sub-pattern in step S5 has its outer edge L1 unobstructed by other metal patterns. Therefore, during the OPC process in step S6, the outer edge L1 of the hot spot pattern can expand outwards without restriction according to a preset rule. This effectively improves the coverage of the hot spot pattern over the via pattern 30, mitigating the defect of insufficient metal layer coverage of vias in the exposure process circuit.

[0052] like Figure 10 As shown, if optical proximity effect correction is performed on the two sub-patterns split in step S2, then in the first sub-pattern... Figure 10 During the correction process, the distance between the outer edge L1 of the first hot spot pattern 100 and the second background pattern 300 is too small, making it difficult to expand the outer edge L1 of the hot spot during the correction process. As a result, the coverage of the first metal pattern 40 over the through hole pattern 30 cannot be improved after the correction process.

[0053] like Figure 11 As shown, in comparison, the solution in this application re-divides the first sub-version after step S5. Figure 10 Optical proximity correction is performed on the second sub-pattern 20, and the first hot spot pattern 100 in the second sub-pattern 20 is assigned to it. The outer edge L1 of the hot spot is no longer restricted by the adjacent second background pattern 300. Therefore, during the correction process of the second sub-pattern 20, the outer edge L1 of the first hot spot pattern 100 can expand outward according to a preset rule, thereby improving the coverage of the first hot spot pattern 100 over the via pattern 30 in the corrected pattern and eliminating the defect of insufficient metal layer coverage of vias after pattern exposure. It should be understood that the sequence number of each step in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0054] Specifically, such as Figure 6 , Figure 7 and Figure 11As shown, the first hotspot pattern 100, which is divided into the second sub-pattern 20, is used as an example. In some embodiments, in step S6, the outer edge L1 of the hotspot in the first hotspot pattern 100 is expanded by a preset displacement. In one embodiment, the preset displacement in step S6 is the difference between a preset enclosure distance E and a fifth distance, where the fifth distance is the shortest distance between the outer edge L1 of the hotspot and the through-hole pattern 30.

[0055] In another embodiment, in step S6, when expanding the outer edge L1 of the hot spot pattern 100 or the second hot spot pattern 400, it is necessary to ensure that the shortest distance between the outer edge L1 of the hot spot and the adjacent background pattern is greater than or equal to the preset split distance.

[0056] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for processing a metal layer layout, characterized in that, include: Obtain the metal layer layout and the corresponding via layer layout; According to a first preset rule, the metal layer layout is divided into at least two sub-layouts, the at least two sub-layouts including a first sub-layout and a second sub-layout; A first hot spot pattern is determined in the first sub-layout according to a second preset rule; the first hot spot pattern surrounds the via pattern of the via layer layout, and the shortest distance between the first hot spot pattern and the via pattern is less than the preset enclosure distance of the via pattern; In the first sub-plot, a first background pattern adjacent to the first hotspot pattern is determined, and in the second sub-plot, a second background pattern adjacent to the first hotspot pattern is determined; wherein, the distance between the first background pattern and the first hotspot pattern is less than or equal to a first preset distance, and the distance between the second background pattern and the first hotspot pattern is less than or equal to a second preset distance; Obtain the shortest first distance between the through-hole pattern and the first background pattern, and obtain the shortest second distance between the first hotspot pattern and the second background pattern; when the difference between the first distance and the preset enclosing distance is less than the second distance, adjust the first hotspot pattern to the second sub-pattern.

2. The processing method according to claim 1, characterized in that, The processing method further includes: A second hot spot pattern is determined in the second sub-layout according to a second preset rule; the second hot spot pattern surrounds the via pattern of the via layer layout, and the shortest distance between the second hot spot pattern and the via pattern is less than the preset enclosure distance of the via pattern; In the second sub-map, a third background pattern adjacent to the second hotspot pattern is determined, and in the first sub-map, a fourth background pattern adjacent to the second hotspot pattern is determined; wherein, the distance between the third background pattern and the second hotspot pattern is less than or equal to a first preset distance, and the distance between the fourth background pattern and the second hotspot pattern is less than or equal to a second preset distance; Obtain the shortest third distance between the through-hole pattern and the third background pattern, and obtain the shortest fourth distance between the second hotspot pattern and the fourth background pattern; when the difference between the third distance and the preset enclosing distance is less than the fourth distance, adjust the second hotspot pattern to the first sub-pattern.

3. The processing method according to claim 2, characterized in that, The step of dividing the metal layer layout into at least two sub-layouts according to a first preset rule includes: A first metal pattern and a second metal pattern with an adjacent spacing less than or equal to a preset split distance are determined, and the first metal pattern is set in the first sub-pattern and the second metal pattern is set in the second sub-pattern.

4. The processing method according to claim 3, characterized in that, The step of dividing the metal layer layout into at least two sub-layouts according to the first preset rule further includes: Identify the unsplit third metal pattern in the metal layer layout; the third metal pattern is located between the first metal pattern and the second metal pattern, and the distance between the third metal pattern and its surrounding adjacent metal patterns is greater than a preset split distance; When the shortest distance between the third metal pattern and the second metal pattern is less than the shortest distance between the third metal pattern and the first metal pattern, the third metal pattern is set in the first sub-pattern. When the shortest distance between the third metal pattern and the first metal pattern is less than the shortest distance between the third metal pattern and the second metal pattern, the third metal pattern is set in the second sub-pattern.

5. The processing method according to claim 3, characterized in that, The first preset distance and the second preset distance are less than the preset split distance.

6. The processing method according to claim 2, characterized in that, The processing method further includes performing optical proximity effect correction processing on the adjusted first sub-pattern and the second sub-pattern respectively; the optical proximity effect correction processing includes: expanding the outer edge of the first hot spot pattern that has the shortest distance to the through hole pattern, and expanding the outer edge of the second hot spot pattern that has the shortest distance to the through hole pattern.

Images