Method for splitting mask layout

Abstract

This invention provides a method for splitting a mask layout, comprising: providing a metal layer layout, the metal layer layout including a plurality of initial metal layer patterns extending along a first direction, the metal layer layout having head-to-head regions between the initial metal layer patterns; providing an initial metal cut-out layer layout, the initial metal cut-out layer layout including a plurality of metal cut-out layer patterns extending along a second direction, the first direction being perpendicular to the second direction; determining that when the size of the head-to-head region in the first direction is less than or equal to a spacing threshold, forming an auxiliary pattern in the head-to-head region based on the initial metal layer patterns; splitting the initial metal cut-out layer layout to form a plurality of transition metal cut-out layer layouts; using the plurality of transition metal cut-out layer layouts as a reference layout, splitting the auxiliary pattern onto at least one transition metal cut-out layer layout, so that the transition metal cut-out layer layout forms a metal cut-out layer layout; thereby improving the efficiency and flexibility of layout splitting.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a method for splitting a mask pattern. Background Technology

[0002] Patterning is an essential process in semiconductor manufacturing. This involves designing a mask pattern based on the semiconductor device. This mask pattern includes several patterns, which are then transferred onto photoresist using photolithography, followed by exposure and development of the photoresist.

[0003] However, with the development of semiconductor technology, the integration density of integrated circuits is increasing, and the feature size of semiconductor devices is becoming smaller. Correspondingly, the requirements for manufacturing processes are becoming more precise, and the number and density of patterns on the mask layout are increasing dramatically. It is becoming increasingly impossible to expose all patterns onto the wafer at once during photolithography. Therefore, MP (Multi-Patterning) technology has become a necessary means to ensure that the exposed patterns meet the process requirements of each node. MP technology splits the relatively dense patterns originally placed on a single mask layout into multiple mask layouts, exposing each one separately to complete the pattern transfer.

[0004] However, there are still many problems with the existing technology of splitting dense graphics onto multiple mask layouts. Summary of the Invention

[0005] The technical problem solved by this invention is to provide a method for splitting a mask layout, so as to improve the efficiency and flexibility of layout splitting.

[0006] The present invention provides a method for splitting a mask layout, comprising: providing a metal layer layout, the metal layer layout including a plurality of initial metal layer patterns extending along a first direction, the metal layer layout having head-to-head regions between the initial metal layer patterns; providing an initial metal cut-out layer layout, the initial metal cut-out layer layout including a plurality of metal cut-out layer patterns extending along a second direction, the first direction being perpendicular to the second direction; determining that when the size of the head-to-head region in the first direction is less than or equal to a spacing threshold, forming an auxiliary pattern in the head-to-head region based on the initial metal layer patterns; splitting the initial metal cut-out layer layout to form a plurality of transition metal cut-out layer layouts; using the plurality of transition metal cut-out layer layouts as reference layouts, splitting the auxiliary pattern onto at least one of the transition metal cut-out layer layouts, so that the transition metal cut-out layer layouts form a metal cut-out layer layout.

[0007] Optionally, the method of splitting the auxiliary graphic onto at least one of the transition metal cut-out layer layouts, using several of the transition metal cut-out layer layouts as reference layouts, further includes: dividing the auxiliary graphic into several auxiliary graphic segments arranged along the second direction; splitting the auxiliary graphic segments and adjacent metal cut-out layer graphics with perpendicular extension directions onto different transition metal cut-out layer layouts, and splitting adjacent auxiliary graphic segments onto different transition metal cut-out layer layouts.

[0008] Optionally, there are no corners between the auxiliary graphic segment and the corresponding split transition metal cut-off layer layout.

[0009] Optionally, the method of dividing the auxiliary pattern into a plurality of auxiliary pattern segments arranged along the second direction includes: forming a derivative pattern between adjacent initial metal layer patterns based on the metal layer layout, the derivative pattern extending along the first direction, the derivative pattern dividing the auxiliary pattern into a plurality of auxiliary pattern segments arranged along the second direction.

[0010] Optionally, the method of dividing the auxiliary graphic into several auxiliary graphic segments arranged along the second direction further includes: reducing the auxiliary graphic segments along the first direction to form transition auxiliary graphic segments, wherein there is no overlap between the line ends of the initial metal layer graphic corresponding to the head-to-head region and the transition metal cut-out layer layout of the transition auxiliary graphic segments along the first direction.

[0011] Optionally, the process of splitting the auxiliary graphic onto at least one of the transition metal cut-out layer layouts includes: splitting the transition auxiliary graphic segment onto at least one of the transition metal cut-out layer layouts; restoring the size of the transition auxiliary graphic segment along the first direction until the size of the transition auxiliary graphic segment is restored to the size of the auxiliary graphic segment.

[0012] Optionally, the derived pattern has a first center line along the first direction, and the adjacent initial metal layer pattern has a second center line in the first direction, with the first center line coinciding with the second center line.

[0013] Optionally, when determining that the size of the head-to-head region in the first direction is less than or equal to the spacing threshold, the method further includes: merging the initial metal layer patterns corresponding to the head-to-head region to form a plurality of metal layer patterns extending along the first direction on the metal layer layout.

[0014] Optionally, the metal layer pattern includes a first metal layer pattern and a second metal layer pattern extending along a first direction, wherein the first metal layer pattern and the second metal layer pattern are distributed at intervals.

[0015] Optionally, after forming the metal layer pattern, the method further includes: splitting the metal layer layout, splitting the first metal layer pattern and the second metal layer pattern into different layouts.

[0016] Optionally, the auxiliary pattern at the head-to-head region overlays the metal cut-out layer pattern.

[0017] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0018] In the mask pattern splitting method of the present invention, the initial metal layer patterns have head-to-head regions. When it is determined that the size of the head-to-head region in the first direction is less than or equal to the spacing threshold, an auxiliary pattern is formed in the head-to-head region. The initial metal cutting layer pattern is split to form several transition metal cutting layer patterns. Using the several transition metal cutting layer patterns as reference patterns, the auxiliary patterns are split to at least one transition metal cutting layer pattern, and the several transition metal cutting layer patterns form several metal cutting layer patterns. As a cutting layer, the pattern of the metal cutting layer pattern is not ultimately transferred to the wafer. The pattern ultimately retained on the wafer is the pattern of the metal cutting layer pattern cutting the metal layer pattern. Therefore, after the auxiliary pattern is split to at least one transition metal cutting layer pattern, it will not affect the splitting of the metal cutting layer pattern, and it is very friendly to the metal cutting layer pattern. The operation is simple and convenient. The split pattern is orderly and uniform, and the pattern type is simple, which is especially suitable for advanced nodes with compact structures.

[0019] Furthermore, when it is determined that the size of the head-to-head region in the first direction is less than or equal to the spacing threshold, the method further includes merging the metal layer patterns corresponding to the head-to-head region to form a metal layer layout. At this time, there is no head-to-head region in the metal layer layout, that is, there are no metal layer patterns of varying lengths, and there are no disconnected ends between the lines of the metal layer patterns. There are only continuous and single metal layer patterns (1D structure), which simplifies the metal layer layout, overcomes the process weaknesses caused by photolithography and etching, and improves the process window and performance. Moreover, the added auxiliary patterns will not affect the splitting of the metal layer layout, which is very friendly to the metal layer layout process.

[0020] Furthermore, based on the metal layer layout, a derivative pattern is formed between adjacent initial metal layer patterns. The derivative pattern extends along the first direction and splits the auxiliary pattern into multiple auxiliary pattern segments. The derivative pattern is used to separate the auxiliary pattern segments from the metal cut-out layer pattern in the second direction. Therefore, during the process of splitting the initial metal cut-out layer layout, some auxiliary patterns will not be split into the transition metal cut-out layer layout.

[0021] Furthermore, the auxiliary graphic segment is reduced along the first direction to form a transition auxiliary graphic segment. The transition auxiliary graphic segment does not overlap with the line end of the corresponding metal layer graphic in the head-to-head region and the transition metal cut layer layout along the first direction. The purpose is to make the transition auxiliary graphic an independent graphic, so that it will not affect the splitting of the metal layer graphic in the metal layer layout or the splitting of the metal cut layer graphic in the initial metal cut layer layout. Attached Figure Description

[0022] Figures 1 to 2 This is a schematic diagram illustrating the steps of a mask pattern splitting method.

[0023] Figure 3 This is a schematic diagram showing the development of one of the patterns after a mask pattern has been split.

[0024] Figure 4 This is a flowchart of the mask layout splitting method according to an embodiment of the present invention;

[0025] Figures 5 to 12 This is a schematic diagram of the steps in the mask pattern splitting method according to an embodiment of the present invention;

[0026] Figure 13 This is a schematic diagram of the structure corresponding to the mask pattern splitting method in another embodiment of the present invention. Detailed Implementation

[0027] As described in the background section, existing techniques for splitting dense patterns onto multiple mask layouts still present numerous problems. These will be explained in detail below with reference to the accompanying drawings.

[0028] Please refer to Figure 1 A mask pattern 100 includes a metal layer pattern 101 and a metal cut-out layer pattern 102. The metal layer pattern 101 includes a plurality of metal layer patterns 101a extending along a first direction (Y), and the metal cut-out layer pattern 102 includes a plurality of metal cut-out layer patterns 102a extending along a second direction (X). The metal layer pattern 101 has head-to-head (HTH) regions 103 between the metal layer patterns 101a.

[0029] Please refer to Figure 2The metal layer layout 101 is split into two layouts, specifically the first layout 104 and the second layout 105. Due to the presence of the head-to-head region 103, the metal layer pattern 101a has various combinations of long bars and short bars. Due to the complexity of this environment, as the nodes continue to shrink, it is often necessary to compensate for etching bias error and model error for these pattern types.

[0030] The inventor discovered this; please refer to [the relevant documentation]. Figure 3 Taking the first pattern 104 as an example, the corresponding developed wafer profile (ADI wafer profile) shows that bridging occurs in the head-to-head region (HTH), and the photoresist profile (PR profile) is uneven in thickness. For example, the feature size CD1 of a short metal layer pattern is small, while the feature size CD2 of the head-to-head HTH region directly opposite the long metal layer pattern is large. The CD of the long and short metal layer patterns differs significantly, resulting in poor feature size uniformity. This causes the process window in this region to be very small, and both DOF (Depth of Focus) and EL (Exposure Latitude) are small. In addition, this type of pattern has a large difference in profile feature size (CD) after etching, which easily leads to defects and yield loss, affecting capacitance and resistance performance, and causing the semiconductor structure performance to fail to meet electrical performance requirements.

[0031] The inventors discovered that the initial metal layer patterns have head-to-head regions. When the size of the head-to-head region in the first direction is less than or equal to the spacing threshold, an auxiliary pattern is formed in the head-to-head region. The initial metal cutting layer layout is split to form several transition metal cutting layer layouts. Using these transition metal cutting layer layouts as reference layouts, the auxiliary pattern is split onto at least one transition metal cutting layer layout, forming several metal cutting layer layouts. As a cutting layer, the pattern of the metal cutting layer layout is not ultimately transferred to the wafer; the final pattern retained on the wafer is the pattern of the metal cutting layer layout cutting the metal layer layout. Therefore, splitting the auxiliary pattern onto at least one transition metal cutting layer layout does not affect the splitting of the metal cutting layer layout and is very friendly to the metal cutting layer layout. The operation is simple and convenient, the split pattern is orderly and uniform, and the pattern type is simple, making it particularly suitable for compact advanced nodes.

[0032] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0033] Figure 4 This is a flowchart of a mask layout splitting method according to an embodiment of the present invention, including:

[0034] Step S101: Provide a metal layer layout and an initial metal cut-out layer layout, wherein the metal layer layout has head-to-head regions between the initial metal layer patterns;

[0035] Step S102: When it is determined that the size of the head-to-head region in the first direction is less than or equal to the spacing threshold, the initial metal layer pattern corresponding to the head-to-head region is merged to form a plurality of metal layer patterns extending along the first direction on the metal layer layout.

[0036] Step S103: An auxiliary pattern is formed in the head-to-head region;

[0037] Step S104: The initial metal cutting layer layout is split to form several transition metal cutting layer layouts.

[0038] Step S105: Using several transition metal cut-out layer layouts as reference layouts, the auxiliary pattern is split into at least one of the transition metal cut-out layer layouts, so that the transition metal cut-out layer layouts form a metal cut-out layer layout.

[0039] The steps of the mask layout splitting method are described in detail below with reference to the accompanying drawings.

[0040] Figures 5 to 12 This is a schematic diagram of the steps in the mask pattern splitting method according to an embodiment of the present invention.

[0041] First, please refer to Figure 5 A metal layer layout 200 is provided, the metal layer layout 200 including a plurality of initial metal layer patterns 202 extending along a first direction, the metal layer layout 200 having head-to-head regions 201 between the initial metal layer patterns 202.

[0042] In this embodiment, the initial metal layer pattern 202 includes a first initial metal layer pattern 202a and a second initial metal layer pattern 202b. The first initial metal layer pattern 202a is elongated, and the second initial metal layer pattern 202b is short. Along the first direction, the ends of the upper and lower lines of the second initial metal layer pattern 202b are not connected, but are separated by a certain distance. This area where the ends of the upper and lower lines of the second initial metal layer pattern 202b are not connected is defined as a head-to-head (HTH) region 201.

[0043] It should be noted that the upper and lower second initial metal layer patterns 202b are on the same straight line.

[0044] In this embodiment, the first direction is defined as the Y-axis direction.

[0045] In this embodiment, the initial metal layer pattern 202 in the metal layer layout 200 is a pattern of a metal layer structure formed on a certain layer of a wafer during semiconductor manufacturing. The environment of the initial metal layer pattern 202 is complex, including long strips and short strips.

[0046] Please continue to refer to this. Figure 5 An initial metal cut layer layout 300 is provided, the initial metal cut layer layout 300 including a plurality of metal cut layer patterns 301 extending along a second direction, the first direction being perpendicular to the second direction.

[0047] In this embodiment, the second direction is defined as the X-axis direction.

[0048] In this embodiment, the metal cut-out layer pattern 301 in the initial metal cut-out layer layout 300 is a pattern of a metal cut-out layer formed on a metal layer structure layer in a semiconductor process. The metal cut-out layer pattern 301 is used to define the position of subsequent metal layers. Since there is a stable spatial positional relationship between the metal layer and the metal layer structure, there is also a stable spatial positional relationship between the corresponding metal layer layout 200 and the initial metal cut-out layer layout 300.

[0049] Since the metal layer layout 200 contains head-to-head regions 201 between the initial metal layer patterns 202, the subsequent developed wafer profile (ADI wafer profile) is prone to bridging in the head-to-head regions (HTH), and there are many problems such as uneven photoresist profile (PR profile). Therefore, by judging the relationship between the size (d) of the head-to-head (HTH) region 201 in the first direction and the spacing threshold, if d is less than or equal to the spacing threshold, then the second initial metal layer pattern 202b in the first direction of the head-to-head (HTH) region 201 can be connected (merged) to form an elongated shape like the first initial metal layer pattern 202a. Then the metal layer pattern is an environmentally unique elongated shape, which reduces the difficulty of subsequent metal layer layout 200 splitting.

[0050] In this embodiment, the spacing threshold is jointly determined by the metal layer (MO) / metal cut-off layer (MOC) process window.

[0051] Please refer to Figure 6 When it is determined that the size (d) of the head-to-head region 201 in the first direction (Y) is less than or equal to the spacing threshold, the initial metal layer pattern 202 corresponding to the head-to-head region 201 is merged to form a plurality of metal layer patterns 203 extending along the first direction (Y) on the metal layer layout 200.

[0052] Specifically, the head-to-head (HTH) regions 201 are connected along the second initial metal layer pattern 202b corresponding to the first direction to form an elongated shape.

[0053] In this embodiment, after merging the initial metal layer patterns 202 corresponding to the head-to-head region 201, they all form elongated shapes with a simple environment. However, if the metal layer patterns 203 are placed on a single layout at this time, due to the large number of metal layer patterns 203, there may be issues such as missing patterns or inaccurate dimensions after development. To improve the accuracy of the metal layer patterns 203, the elongated metal layer patterns 203 are divided into two types of patterns. Specifically, the metal layer patterns 203 include a first metal layer pattern 203a and a second metal layer pattern 203b extending along the first direction (Y). The first metal layer pattern 203a and the second metal layer pattern 203b are distributed alternately, which facilitates the subsequent splitting of the metal layer layout 200, reduces the density of the metal layer patterns on the split layout, and helps improve the accuracy of the metal layer patterns.

[0054] In this embodiment, if it is determined that the size (d) of the head-to-head region 201 in the first direction (Y) is greater than the spacing threshold, then the head-to-head region 201 is retained, and subsequent etching bias error and model error are compensated by detailed analysis of the After Development Inspection (ADI) stage and the After Etch Inspection (AEI) stage.

[0055] Please refer to Figure 7 The initial metal layer pattern 202 is merged, and the metal layer layout 200 is split, with the first metal layer pattern 203a and the second metal layer pattern 203b split into different layouts.

[0056] In this embodiment, the first metal layer pattern 203a is split into the first layout 204, and the second metal layer pattern 203b is split into the second layout 205.

[0057] In this embodiment, since the initial metal layer pattern 202 corresponding to the head-to-head region 201 is merged when the size of the head-to-head region 201 in the first direction (Y) is determined to be less than or equal to the spacing threshold, if an auxiliary pattern is not added to the corresponding head-to-head region 201, the actual design of the final pattern will be different, which will lead to the failure of the final semiconductor structure.

[0058] Please refer to Figure 8 Based on the initial metal layer pattern 202, an auxiliary pattern 400 is formed in the head-to-head region 201.

[0059] In the picture Figure 8 Is Figure 6 It was drawn based on that.

[0060] In this embodiment, the auxiliary graphic 400 overlaps with the metal cut-out layer pattern 300 at the head-to-head region 201 in the first direction (Y), that is, the auxiliary graphic 400 partially overlaps with the metal cut-out layer graphic segment on the metal cut-out layer pattern 300, and the auxiliary graphic 400 covers the metal cut-out layer pattern 301.

[0061] In this embodiment, during the formation of the auxiliary pattern 400, the auxiliary pattern 400 is appropriately extended along the second direction (X) to ensure that the auxiliary pattern 400 can cut off the merged metal layer pattern 203, so that the final metal layer pattern is the same as the design, ensuring the accuracy of the pattern.

[0062] Please refer to Figure 9 The initial metal cutting layer layout 300 is split to form several transition metal cutting layer layouts 302.

[0063] In this embodiment, after splitting the initial metal cut layer pattern 300, the metal cut layer pattern 301 is split into four transition metal cut layer patterns, including a first transition metal cut layer pattern 302a, a second transition metal cut layer pattern 302b, a third transition metal cut layer pattern 302c, and a fourth transition metal cut layer pattern 302d.

[0064] In this embodiment, after the initial metal cut layer layout 300 is split, the metal cut layer pattern 301 is split into multiple metal cut layer pattern segments and assigned to different transition metal cut layer layouts.

[0065] Using several transition metal cut-out layer layouts 302 as reference layouts, the auxiliary pattern 400 is split, and the auxiliary pattern 400 is split onto at least one of the transition metal cut-out layer layouts 302, so that the transition metal cut-out layer layouts 302 form metal cut-out layer layouts. Please refer to [the relevant documentation for the process]. Figures 10 to 12 .

[0066] Please refer to Figure 10 Based on the metal layer layout 200, a derivative pattern 500 is formed between adjacent initial metal layer patterns 202. The derivative pattern 500 extends along the first direction (Y) and divides the auxiliary pattern 400 into a plurality of auxiliary pattern segments 401.

[0067] In this embodiment, the derived pattern 500 has a first center line along the first direction (Y), and the adjacent initial metal layer pattern 202 has a second center line along the first direction (Y), with the first center line coinciding with the second center line.

[0068] In this embodiment, the auxiliary graphic segment 401 and the metal cut-out layer graphic 301 are separated in the second direction (X) using the derived graphic 500, so that during the process of splitting the initial metal cut-out layer layout 300, part of the auxiliary graphic 400 will not be split into the transition metal cut-out layer layout.

[0069] Please refer to Figure 11 The auxiliary graphic segment 401 is reduced along the first direction (Y) to form a transition auxiliary graphic segment 402. The transition auxiliary graphic segment 402 does not overlap with the line end of the initial metal layer pattern 202 corresponding to the head-to-head region 201 and the transition metal cut-out layer layout 302 along the first direction (Y).

[0070] In this embodiment, specifically, the line ends of the transition auxiliary graphic segment 402 and the second initial metal layer graphic 202b do not overlap, and there is no overlap between the transition auxiliary graphic segment 402 and the transition metal cut-off layer layout 302 adjacent to the head-to-head region 201. To show that they do not overlap, a certain gap is drawn between the three in the figure.

[0071] In this embodiment, the auxiliary graphic segment 401 is reduced along the first direction to form the transition auxiliary graphic segment 402. The transition auxiliary graphic segment 402 does not overlap with the line ends of the second initial metal layer graphic 202b in the first direction. The purpose is to ensure that the transition auxiliary graphic segment 402 does not overlap with the initial metal layer graphic 202 in the first direction, and that there is no overlap between it and the transition metal cut-out layer layout 302 adjacent to the head-to-head region 201. Combined with the derived graphic 500, the transition auxiliary graphic 402 becomes an independent graphic, so that it does not affect the splitting of the metal layer layout 200 and the initial metal cut-out layer layout 300.

[0072] Please refer to Figure 12 The process of splitting the auxiliary graphic 400 into at least one of the transition metal cut-out layer layouts 302 includes restoring the size of the transition auxiliary graphic segment 402 until the size of the transition auxiliary graphic segment 402 is restored to the size of the auxiliary graphic segment 401.

[0073] In this embodiment, the auxiliary graphic 400 is divided into a plurality of auxiliary graphic segments 401 arranged along the second direction; the auxiliary graphic segments 401 and the adjacent metal cutting layer graphic 301 with perpendicular extension directions are split onto different transition metal cutting layer layouts 302, and adjacent auxiliary graphic segments 401 are split onto different transition metal cutting layer layouts 302.

[0074] In this embodiment, the auxiliary graphic segment 401 and the adjacent metal cut layer graphic 301 extending perpendicularly are split onto different transition metal cut layer layouts 302, and adjacent auxiliary graphic segments 401 are split onto different transition metal cut layer layouts 302. The purpose is to ensure that only graphics extending in one direction exist on the same layout, and there are no graphics with corners. This simplifies the complexity of the graphics and ensures that the graphics are not distorted during the development and exposure process, thereby improving the accuracy of the graphics.

[0075] For details, please refer to Figure 12The diagram illustrates two head-to-head (HTH) regions 201. Taking the first HTH region 201 from the left as an example, this region 201 contains the fourth transition metal cut-out layer pattern 302d and the second transition metal cut-out layer pattern 302b. If the auxiliary graphic segment 401 is split onto either the fourth transition metal cut-out layer pattern 302d or the second transition metal cut-out layer pattern 302b, a corner exists between the metal cut-out layer graphic segment on either pattern 302d or the second transition metal cut-out layer pattern 302b and the auxiliary graphic segment 401. Such corners result in poor quality or even missing graphics during subsequent development. Therefore, the only option is to split the auxiliary graphic segment 401 onto either the first transition metal cut-out layer pattern 302a or the third transition metal cut-out layer pattern 302c. Figure 12 The leftmost auxiliary graphic segment 401 is split onto the first transition metal cutting layer layout 302a.

[0076] When splitting the auxiliary graphic segment 401 onto different transition metal cutting layer layouts, it is necessary to consider not only whether there will be corners between the metal cutting layer graphic segment and the auxiliary graphic segment on the split transition metal cutting layer layout, but also that the auxiliary graphic segment on the transition metal cutting layer layout cannot be too large. Therefore, if the second auxiliary graphic segment 401 from left to right is also split onto the first transition metal cutting layer layout 302a, then the size of the auxiliary graphic segment 401 on the first transition metal cutting layer layout 302a would be too large, which does not conform to the splitting rules. Therefore, the second auxiliary graphic segment 401 can only be split onto the third transition metal cutting layer layout 302c, and so on, with the third auxiliary graphic segment 401 being split onto the first transition metal cutting layer layout 302a.

[0077] Similarly, please refer to Figure 12 Taking the three auxiliary graphic segments 401 within the second head-to-head (HTH) region 201 as an example, the head-to-head (HTH) region 201 has the fourth transition metal cutting layer layout 302d and the first transition metal cutting layer layout 302a. Therefore, the leftmost auxiliary graphic segment 401 can be split onto the third transition metal cutting layer layout 302c or the second transition metal cutting layer layout 302b. If the leftmost auxiliary graphic segment 401 is split onto the third transition metal cutting layer layout 302c, the middle auxiliary graphic segment 401 is split onto the second transition metal cutting layer layout 302b, and the rightmost auxiliary graphic segment 401 is split onto the third transition metal cutting layer layout 302c.

[0078] In another embodiment, please refer to Figure 13 Starting from the left, in the first head-to-head (HTH) region 201, the leftmost first auxiliary graphic segment 401 is split onto the third transition metal cutting layer layout 302c; the second auxiliary graphic segment 401 is split onto the first transition metal cutting layer layout 302a; the third auxiliary graphic segment 401 is split onto the third transition metal cutting layer layout 302c; in the second head-to-head (HTH) region 201, the leftmost auxiliary graphic segment 401 is split onto the second transition metal cutting layer layout 302b, the middle auxiliary graphic segment 401 is split onto the third transition metal cutting layer layout 302c, and the rightmost auxiliary graphic segment 401 is split onto the second transition metal cutting layer layout 302b.

[0079] In this embodiment, the metal cut-out layer layout has the characteristic of a cutting layer. The pattern of the metal cut-out layer layout is not ultimately transferred to the wafer. Instead, the pattern ultimately retained on the wafer is the pattern of the metal cut-out layer layout cutting the metal layer layout. Therefore, after the auxiliary pattern is split into at least one transition metal cut-out layer layout, the transition metal cut-out layer layout forms the metal cut-out layer layout. This not only does not affect the splitting of the metal cut-out layer layout, but is also very friendly to the metal cut-out layer layout. The operation is simple and convenient. After splitting, the pattern is orderly and uniform, and the pattern type is simple, which is especially suitable for advanced nodes with compact structures.

[0080] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A method for splitting a mask layout, characterized in that, include: A metal layer layout is provided, the metal layer layout including a plurality of initial metal layer patterns extending along a first direction, the metal layer layout having head-to-head regions between the initial metal layer patterns; An initial metal cut layer layout is provided, the initial metal cut layer layout comprising a plurality of metal cut layer patterns extending along a second direction, the first direction being perpendicular to the second direction; When it is determined that the size of the head-to-head region in the first direction is less than or equal to the spacing threshold, an auxiliary pattern is formed in the head-to-head region based on the initial metal layer pattern. The initial metal cut-out layer layout is split to form several transition metal cut-out layer layouts; Using several transition metal cut-out layer layouts as reference layouts, the auxiliary pattern is split and distributed onto at least one of the transition metal cut-out layer layouts, so that the transition metal cut-out layer layouts form metal cut-out layer layouts.

2. The method for splitting a mask layout as described in claim 1, characterized in that, Using several transition metal cut-out layer layouts as reference layouts, the method of splitting the auxiliary graphics onto at least one of the transition metal cut-out layer layouts further includes: dividing the auxiliary graphics into several auxiliary graphic segments arranged along the second direction; splitting the auxiliary graphic segments and adjacent metal cut-out layer graphics with perpendicular extension directions onto different transition metal cut-out layer layouts, and splitting adjacent auxiliary graphic segments onto different transition metal cut-out layer layouts.

3. The method for splitting a mask layout as described in claim 2, characterized in that, There are no corners between the auxiliary graphic segment and the corresponding split transition metal cut-off layer layout.

4. The method for splitting a mask layout as described in claim 2, characterized in that, The method of dividing the auxiliary pattern into a plurality of auxiliary pattern segments arranged along the second direction includes: forming a derivative pattern between adjacent initial metal layer patterns based on the metal layer layout, the derivative pattern extending along the first direction, the derivative pattern dividing the auxiliary pattern into a plurality of auxiliary pattern segments arranged along the second direction.

5. The method for splitting a mask layout as described in claim 4, characterized in that, The method of dividing the auxiliary graphic into a plurality of auxiliary graphic segments arranged along the second direction further includes: reducing the auxiliary graphic segments along the first direction to form transition auxiliary graphic segments, wherein there is no overlap between the line ends of the initial metal layer graphic corresponding to the head-to-head region and the transition metal cut-out layer layout of the transition auxiliary graphic segments along the first direction.

6. The method for splitting a mask layout as described in claim 5, characterized in that, The process of splitting the auxiliary graphic onto at least one of the transition metal cut-out layer layouts includes: splitting the transition auxiliary graphic segment onto at least one of the transition metal cut-out layer layouts; restoring the size of the transition auxiliary graphic segment along the first direction until the size of the transition auxiliary graphic segment is restored to the size of the auxiliary graphic segment.

7. The method for splitting a mask layout as described in claim 4, characterized in that, The derived pattern has a first center line along the first direction, and the adjacent initial metal layer pattern has a second center line in the first direction, with the first center line coinciding with the second center line.

8. The method for splitting a mask layout as described in claim 1, characterized in that, When it is determined that the size of the head-to-head region in the first direction is less than or equal to the spacing threshold, the method further includes: merging the initial metal layer patterns corresponding to the head-to-head region to form a plurality of metal layer patterns extending along the first direction on the metal layer layout.

9. The method for splitting a mask layout as described in claim 8, characterized in that, The metal layer pattern includes a first metal layer pattern and a second metal layer pattern extending along a first direction, with the first metal layer pattern and the second metal layer pattern distributed at intervals.

10. The method for splitting a mask layout as described in claim 9, characterized in that, After forming the metal layer pattern, the method further includes: splitting the metal layer layout, splitting the first metal layer pattern and the second metal layer pattern into different layouts.

11. The method for splitting a mask layout as described in claim 1, characterized in that, The auxiliary pattern at the head-to-head region is overlaid on the metal cut-out layer pattern.

Images