Special Unit Total Database and its Establishment Method, Graphic Correction Method

Abstract

A special unit database and its establishment method, and a pattern correction method are disclosed. The pattern correction method includes: providing a layout to be corrected, the layout including a region to be corrected and a special unit structure region to be corrected; obtaining the minimum repeating unit pattern to be corrected in the special unit structure region; providing a special unit database; obtaining information on the unit correction pattern corresponding to the minimum repeating unit pattern to be corrected from the special unit database; performing optical proximity correction on the region to be corrected to obtain information on a second correction pattern; and obtaining a corrected layout based on the information of the second correction pattern and the information of the unit correction pattern. The correction efficiency of the pattern correction method is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing, and in particular to a special unit database and its establishment method, as well as a graphic correction method. Background Technology

[0002] Many design layouts contain special cell structures, such as SRAM and pixel cells, and the number of these special cell structures is limited across different platform companies. As chip size increases, the number of repetitive structures at different locations within these special cells also increases. Therefore, the computational load for these special cell regions is significant during Optical Proximity Correction (OPC), leading to repeated calculations of OPC results for the same special cell structure across different products, resulting in a waste of OPC resources. Furthermore, OPC results for special cell regions often contain issues, requiring OPC personnel to spend considerable time and effort troubleshooting.

[0003] To better perform optical proximity correction, classification is essential for identifying special unit regions. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a special unit total database and its establishment method, as well as a graphic correction method, so as to improve the efficiency of optical proximity correction.

[0005] To address the aforementioned technical problems, the present invention provides a method for establishing a special unit total database for graphic correction, comprising: providing a design layout, the design layout including several special unit structure regions, each special unit structure region including several graphics; obtaining the smallest repeating unit graphic in the special unit structure regions; establishing a special unit structure database based on the information of the smallest repeating unit graphic; obtaining a first corrected layout after design layout correction, the first corrected layout having unit correction graphics corresponding to the smallest repeating unit graphic; establishing a special unit correction result database based on the information of the several unit correction graphics; and establishing a special unit total database based on the special unit structure database and the special unit correction result database, wherein in the special unit total database, the information of each smallest repeating unit graphic and the information of each unit correction graphic correspond one-to-one.

[0006] Optionally, the method for obtaining the minimum repeating unit graphic in a special unit structure region includes: selecting a feature graphic according to preset conditions; obtaining a feature vector of the feature graphic based on the feature graphic; obtaining a graphic that conforms to the feature vector in the design layout based on the feature vector; taking any endpoint of the side length of the feature graphic as a first vertex, extending it along a preset length along a first direction and a second direction that are perpendicular to each other, to obtain the minimum repeating unit region, wherein the shape of the minimum repeating unit region is a rectangle, and the graphic in the minimum repeating unit region is the minimum repeating unit graphic.

[0007] Optionally, the preset conditions include: the number of side lengths of the feature graphic is greater than or equal to 6.

[0008] Optionally, the parameters of the feature vector include one or a combination of multiple of the following: area of ​​the figure, number of vertices, effective side length, and included angle of the sides.

[0009] Optionally, the information of the minimum repeating unit graphic includes the original matrix information, rotation matrix information, and mirror matrix information.

[0010] Optionally, the method for obtaining information about the smallest repeating unit graphic in a special unit structure region includes: converting the smallest repeating unit graphic into a two-dimensional original matrix to obtain the original matrix information of the smallest repeating unit; rotating and mirroring the two-dimensional original matrix to obtain the rotation matrix information and mirror matrix information of the smallest repeating unit.

[0011] Optionally, the method for converting the minimum repeating unit graphic into a two-dimensional original matrix includes: obtaining the minimum covering area of ​​the minimum repeating unit graphic, wherein the shape of the minimum covering area is rectangular; using each vertex of the minimum repeating unit graphic as a fixed point, extending along a first direction and a second direction to the boundary of the minimum repeating unit graphic to construct grid cells; according to the filling status of the grid cells, each empty grid cell is replaced with 0, and each fully filled grid cell is replaced with 1, to obtain an initial original matrix represented by 0 and 1, wherein each grid cell of the initial original matrix has a row height and a column width; obtaining the cell value according to the row height and column width of each cell of the initial original matrix, to obtain the two-dimensional original matrix.

[0012] Optionally, the original two-dimensional matrix is ​​m rows × n columns, and the rotation matrix information includes: for any element Aij in the original m×n matrix, the coordinates after rotating 90° are (j, mi-1), the coordinates after rotating 180° are (mi-1, nj-1), and the coordinates after rotating 270° are (nj-1, i); the mirror matrix information includes: for any element Aij in the original m×n matrix, the coordinates after horizontal mirroring are (i, n-j+1), and the coordinates after vertical mirroring are (m-i+1, j).

[0013] Optionally, the row height and column width of the grid cells in the initial original matrix are calculated as follows: the minimum coverage area is uniformly divided into several sub-columns along the first direction, with some sub-column lines coinciding with the outline of the minimum repeating unit graphic parallel to the second direction; the minimum coverage area is uniformly divided into several sub-rows along the second direction Y, with some sub-row lines coinciding with the outline of the minimum repeating unit graphic parallel to the first direction; the number of sub-columns in the first direction of each grid cell is calculated to obtain the row height of the grid cell; the number of sub-rows in the second direction of each grid cell is calculated to obtain the column width of the grid cell.

[0014] Optionally, the two adjacent contour lines of the minimum repeating unit graphic are perpendicular to each other.

[0015] Optionally, the angle between two adjacent contour lines of the smallest repeating unit graphic is an obtuse angle or an acute angle, and some of the grid cells are partially filled; the area of ​​the filled part is the value of the two-dimensional original matrix of the partially filled grid cell.

[0016] Optionally, the method for obtaining the area of ​​the filled portion includes: obtaining the number of columns in the sub-column and the number of rows in the sub-row corresponding to the partially filled grid cell; and calculating the area of ​​the filled portion of the partially filled grid cell based on the number of columns in the sub-column and the number of rows in the sub-row.

[0017] Optionally, the method for obtaining the cell correction pattern corresponding to the minimum repeating cell pattern includes: obtaining the minimum repeating cell pattern according to a special cell structure database; and obtaining the cell correction pattern corresponding to the minimum repeating cell pattern according to the first correction layout.

[0018] Optionally, before obtaining the cell correction pattern corresponding to the minimum repeating cell pattern according to the first correction layout, the method further includes: determining whether the minimum repeating cell pattern is located at the boundary of a special cell structure region; if the minimum repeating cell pattern is not located at the boundary of a special cell structure region, then obtaining the cell correction pattern corresponding to the minimum repeating cell pattern according to the first correction layout.

[0019] Optionally, the method for determining whether the minimum repeating unit graphic is located at the boundary of the special unit structure region includes: taking any endpoint of the side length of the minimum repeating unit graphic as a second vertex, extending it by a preset length along a first direction and a second direction that are perpendicular to each other to obtain an extended region, wherein the selection rule for the second vertex is the same as the selection rule for the first vertex; taking the minimum repeating unit graphic as the center, obtaining the number of second vertices around the minimum repeating unit graphic in the extended region; if the number of second vertices around the minimum repeating unit graphic in the extended region is greater than or equal to 4, then determining that the minimum repeating unit graphic is not located at the boundary of the special unit structure region; if the number of second vertices around the minimum repeating unit graphic in the extended region is less than 4, then determining that the minimum repeating unit graphic is located at the boundary of the special unit structure region.

[0020] Accordingly, the present invention also provides a special unit total database established using the above method.

[0021] Accordingly, the present invention also provides a pattern correction method, comprising: providing a pattern to be corrected, the pattern to be corrected including a region to be corrected and a special unit structure region to be corrected; obtaining the minimum repeating unit pattern to be corrected in the special unit structure region; providing a special unit total database; obtaining information of the unit correction pattern corresponding to the minimum repeating unit pattern to be corrected in the special unit total database; performing optical proximity correction on the region to be corrected to obtain information of a second correction pattern; and obtaining a corrected pattern based on the information of the second correction pattern and the information of the unit correction pattern.

[0022] Optionally, before obtaining the information of the cell correction pattern corresponding to the minimum repeating cell pattern to be corrected from the special cell database, the method further includes: determining whether the minimum repeating cell pattern to be corrected is located at the boundary of the special cell structure region to be corrected.

[0023] Optionally, if the minimum repeating unit pattern to be corrected is not located at the boundary of the special unit structure region to be corrected, the corrected layout is obtained based on the information of the second corrected pattern and the information of the unit corrected pattern.

[0024] Optionally, if the minimum repeating unit pattern to be corrected is located at the boundary of the special unit structure region to be corrected, then optical proximity correction is performed on the minimum repeating unit pattern to be corrected at the boundary to obtain information of the third corrected pattern; and the corrected layout is obtained based on the information of the second corrected pattern, the unit corrected pattern information and the information of the third corrected pattern.

[0025] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0026] The technical solution of the present invention obtains a total database of special units through the special unit structure database and the special unit correction result database. The information of the smallest repeating unit graphic in the total database of special units corresponds one-to-one with the information of each unit correction graphic. When correcting the layout to be corrected, only the area to be corrected can be corrected. The correction result of the special unit structure area to be corrected can be directly obtained from the total database of special units, thereby saving the calculation time of optical proximity correction.

[0027] Furthermore, after obtaining the minimum repeating unit pattern to be corrected in the special unit structure region, the method further includes: determining whether the minimum repeating unit pattern is located at the boundary of the special unit structure region. If the minimum repeating unit pattern is located at the boundary of the special unit structure region, then optical proximity correction is performed on the minimum repeating unit pattern to improve the accuracy of optical proximity correction. Attached Figure Description

[0028] Figure 1 and Figure 2 This is a schematic diagram of the unit graphic structure in one embodiment;

[0029] Figures 3 to 7 This is a flowchart of the method for establishing a total database of special units for graphic correction in an embodiment of the present invention;

[0030] Figure 8 This is a flowchart of the graphic correction method in an embodiment of the present invention;

[0031] Figures 9 to 21 This is a schematic diagram of the process of establishing a general database for a special unit in an embodiment of the present invention. Detailed Implementation

[0032] As described in the background section, classification is essential for identifying specific unit regions. This will now be analyzed and explained in conjunction with specific embodiments.

[0033] Figure 1 and Figure 2 This is a schematic diagram of a unit graphic structure in one embodiment.

[0034] Please refer to Figure 1 and Figure 2 , Figure 2 for Figure 1 A schematic diagram of the unit graphic structure rotated 90 degrees. Figure 1 and Figure 2 The unit structure diagram described herein includes: a first diagram 101, a second diagram 102, and a third diagram 103.

[0035] Figure 1 and Figure 2The unit graphic structures are the same, only their placement on different layouts is different, and it is difficult to distinguish whether the graphic structure is rotated or mirrored, so it is impossible to accurately identify the smallest repeating unit in a special unit area.

[0036] To address the aforementioned issues, the present invention provides a special unit total database and its establishment method, as well as a graphic correction method. The special unit total database is obtained through the special unit structure database and the special unit correction result database. The information of the smallest repeating unit graphic in the special unit total database corresponds one-to-one with the information of each unit correction graphic. When correcting the layout to be corrected, only the area to be corrected can be corrected. The correction results for the special unit structure area to be corrected can be directly obtained from the special unit total database, thereby saving computation time for optical proximity correction.

[0037] To make the above-mentioned objectives, features and beneficial effects 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.

[0038] Figures 3 to 7 This is a flowchart of the method for establishing a total database of special units for graphic correction in an embodiment of the present invention.

[0039] Please refer to Figure 3 The method for establishing the total database of special units for graphic correction includes:

[0040] Step S10: Provide a design layout, the design layout including several special unit structure regions, the special unit structure regions including several graphics;

[0041] Step S20: Obtain the smallest repeating unit graphic in the special unit structure region;

[0042] Step S30: Establish a special unit structure database based on the information of the minimum repeating unit graphic;

[0043] Step S40: Obtain the first revised layout after the design layout is corrected. The first revised layout has a unit revised pattern corresponding to the smallest repeating unit pattern.

[0044] Step S50: Establish a database of special unit correction results based on the information of several unit correction graphics;

[0045] Step S60: Establish a total database of special units based on the special unit structure database and the special unit correction result database, and in the total database of special units, the information of each minimum repeating unit graphic and the information of each unit correction graphic correspond one-to-one.

[0046] The special unit structure database and the special unit correction result database are used to obtain the special unit total database. The information of the smallest repeating unit graphic in the special unit total database corresponds one-to-one with the information of each unit correction graphic. When correcting the layout to be corrected, only the area to be corrected can be corrected. The correction result of the special unit structure area to be corrected can be directly obtained from the special unit total database, thereby saving the calculation time of optical proximity correction.

[0047] Next, each step will be explained separately.

[0048] Please continue to refer to this. Figure 3 Step S10: Provide a design layout, which includes several special unit structure regions, and the special unit structure regions include several graphics.

[0049] The special unit structure region has several repeating unit patterns, such as the storage unit of dynamic random access memory (SRAM) and the pixel unit of pixel structure.

[0050] Please continue to refer to this. Figure 3 Step S20: Obtain the smallest repeating unit graphic in the special unit structure region.

[0051] Please refer to Figure 4 In this embodiment, the method for obtaining the smallest repeating unit pattern in a special unit structure region includes:

[0052] Step S201: Select a feature graphic according to preset conditions;

[0053] Step S202: Obtain the feature vector of the feature graphic based on the feature graphic;

[0054] Step S203: Obtain a graphic that conforms to the feature vector in the design layout based on the feature vector;

[0055] Step S204: Using any endpoint of the side length of the feature graphic as the first vertex, extend it by a preset length along a first direction and a second direction that are perpendicular to each other to obtain the minimum repeating unit region. The shape of the minimum repeating unit region is a rectangle, and the graphic in the minimum repeating unit region is the minimum repeating unit graphic.

[0056] Please continue to refer to this. Figure 4 Step S201: Select feature graphics according to preset conditions.

[0057] In this embodiment, the preset condition includes: the number of side lengths of the feature graphic is greater than or equal to 6.

[0058] If a number of graphics in the special unit structure region meet the condition that the number of side lengths is greater than or equal to 6, then it can be identified as a characteristic graphic.

[0059] The preset conditions can be formulated according to the actual situation of the semiconductor structure.

[0060] Please refer to Figure 9 , Figure 9 This is a schematic diagram of the feature pattern A, which has six side lengths: L1, L2, L3, L4, L5, and L6.

[0061] Please continue to refer to this. Figure 4 Step S202: Obtain the feature vector of the feature graphic based on the feature graphic.

[0062] In this embodiment, the parameters of the feature vector include one or a combination of multiple of the following: area of ​​the figure, number of vertices, effective side length, and included angle of the sides.

[0063] Please continue to refer to this. Figure 9 The parameters of the feature vector of the feature graphic A include the effective side length and the angle between the sides. The feature vector is [L1,a1,L2,a2,L3,a3,L4,a4,L5,a5,L6,a6], where a1 is the angle between L1 and L2, a2 ​​is the angle between L2 and L3, a3 is the angle between L3 and L4, a4 ​​is the angle between L4 and L5, a5 is the angle between L5 and L6, and a6 is the angle between L6 and L1.

[0064] Please continue to refer to this. Figure 4 Step S203: Obtain a graphic that conforms to the feature vector in the design layout according to the feature vector.

[0065] Different shapes have different feature vectors. When the feature vectors of two shapes are the same, the two shapes can be considered to be the same shape.

[0066] Please continue to refer to this. Figure 4 Step S204: Using any endpoint of the side length of the feature graphic as the first vertex, extend the region by a preset length along the first and second mutually perpendicular directions to obtain the minimum repeating unit region. The shape of the minimum repeating unit region is a rectangle, and the graphic within the minimum repeating unit region is the minimum repeating unit graphic.

[0067] Please refer to Figure 10 , Figure 10This is a schematic diagram of the minimum repeating unit region C. In this embodiment, the left endpoint B of L1 is selected as the vertex, and the region is expanded along a certain preset length along the mutually perpendicular first direction X and second direction Y. The resulting rectangular region C is the minimum repeating unit region C. The feature graphic A is located within the minimum repeating unit region C.

[0068] The preset length for expansion along the first direction X and the second direction Y is specifically set according to different special unit structures.

[0069] Please continue to refer to this. Figure 3 Step S30: Establish a special unit structure database based on the information of the minimum repeating unit graphic.

[0070] In this embodiment, the information of the smallest repeating unit graphic includes the original matrix information, rotation matrix information, and mirror matrix information.

[0071] Please refer to Figure 5 In this embodiment, the method for obtaining information about the smallest repeating unit graphic in a special unit structure region includes:

[0072] Step S301: Convert the minimum repeating unit graphic into a two-dimensional original matrix and obtain the original matrix information of the minimum repeating unit;

[0073] Step S302: Rotate and mirror the original two-dimensional matrix to obtain the rotation matrix information and mirror matrix information of the smallest repeating unit. The information of the smallest repeating unit graphic includes the original matrix information, rotation matrix information and mirror matrix information.

[0074] Please continue to refer to this. Figure 5 Step S301: Convert the minimum repeating unit graphic into a two-dimensional original matrix and obtain the original matrix information of the minimum repeating unit.

[0075] Please refer to Figure 6 In this embodiment, the method for converting the smallest repeating unit graphic into a two-dimensional original matrix includes:

[0076] Step S3011: Obtain the minimum coverage area of ​​the minimum repeating unit graphic, wherein the shape of the minimum coverage area is a rectangle;

[0077] Step S3012: Using each vertex of the minimum repeating unit graphic as a fixed point, extend along the first direction and the second direction to the boundary of the minimum repeating unit graphic to construct a grid cell;

[0078] Step S3013: Based on the filling status of the grid cells, each empty grid cell is replaced with 0, and each fully filled grid cell is replaced with 1, to obtain an initial original matrix represented by 0 and 1, wherein each grid cell of the initial original matrix has a row height and a column width;

[0079] Step S3014: Obtain the cell value based on the row height and column width of each cell in the initial original matrix, and obtain the two-dimensional original matrix.

[0080] Please continue to refer to this. Figure 6 Step S3011: Obtain the minimum coverage area of ​​the minimum repeating unit graphic, wherein the shape of the minimum coverage area is a rectangle.

[0081] The minimum repeating unit graphic is located within the minimum coverage area, and the boundary of the minimum coverage area coincides with the boundary of the minimum repeating graphic.

[0082] Please refer to Figure 11 In this embodiment, the minimum coverage area of ​​the minimum repeating unit pattern S1 is D.

[0083] Please continue to refer to this. Figure 6 Step S3012: Using each vertex of the minimum repeating unit graphic as a fixed point, extend along the first direction and the second direction to the boundary of the minimum repeating unit graphic to construct a grid cell.

[0084] Please refer to Figure 12 In this embodiment, each vertex of the minimum repeating unit graphic S1 is used as a fixed point, and the grid cells Gij are constructed by extending along the first direction X and the second direction Y to the boundary of the minimum repeating unit graphic S1.

[0085] In this embodiment, the two adjacent contour lines of the smallest repeating unit graphic S1 are perpendicular to each other.

[0086] Please continue to refer to this. Figure 6 Step S3013: Based on the filling status of the grid cells, each empty grid cell is replaced with 0, and each fully filled grid cell is replaced with 1, to obtain an initial original matrix represented by 0 and 1, wherein each grid cell of the initial original matrix has a row height and a column width.

[0087] The calculation method for the row height and column width of the grid cells of the initial original matrix is ​​as follows: the minimum coverage area D is uniformly divided into several sub-columns along the first direction X, with some sub-column lines coinciding with the outline of the minimum repeating unit graphic S1 parallel to the outline of the second direction Y; the minimum coverage area D is uniformly divided into several sub-rows along the second direction Y, with some sub-row lines coinciding with the outline of the minimum repeating unit graphic S1 parallel to the first direction X; the number of sub-columns in the first direction X of each column of grid cells is calculated to obtain the row height of the grid cell; the number of sub-rows in the second direction Y of each row of grid cells is calculated to obtain the column width of the grid cell.

[0088] Please refer to Figure 13 In this embodiment, each grid cell Gij of the initial original matrix has a row height Wi and a column width Hj.

[0089] In this embodiment, the initial original matrix values ​​obtained based on the filling status of the grid cells Gij are: G11=0, G12=0, G13=0, G14=1, G21=1, G22=1, G23=0, G24=1, G31=0, G32=1, G33=0, G34=1, G41=0, G42=1, G43=0, G44=0.

[0090] Please continue to refer to this. Figure 6 Step S3014: Obtain the cell value based on the row height and column width of each grid cell in the initial original matrix, and obtain the two-dimensional original matrix.

[0091] The method for determining the value of the original two-dimensional matrix is ​​as follows: the value of a cell with grid cell Gij equal to 0 is 0, and the value of a cell with grid cell Gij equal to 1 is: height Wi × column width Hj.

[0092] Please refer to Figure 14 , Figure 14 In order to be in Figure 13 Based on the schematic diagram, in this embodiment, W1=5, W2=4, W3=3, W4=2, H1=4, H2=4, H3=2, H4=3.

[0093] The original two-dimensional matrix has the following values: G11 = 0, G12 = 0, G13 = 0, G14 = W1 × H4 = 15, G21 = W2 × H1 = 16, G22 = W2 × H2 = 16, G23 = 0, G24 = W2 × H4 = 12, G31 = 0, G32 = W3 × H2 = 12, G33 = 0, G34 = W3 × H4 = 9, G41 = 0, G42 = W4 × H2 = 8, G43 = 0, G44 = 0.

[0094] In other embodiments, when the angle between two adjacent contour lines of the smallest repeating unit graphic is an obtuse angle or an acute angle, there will be partially filled grid cells in the grid cell. At this time, the area of ​​the filled part in the partially filled grid cell is obtained, which is the value of the two-dimensional original matrix of the partially filled grid cell.

[0095] The method for obtaining the area of ​​the filled portion includes: obtaining the number of columns and the number of rows of the sub-column corresponding to the partially filled grid cell; and calculating the area of ​​the filled portion of the partially filled grid cell based on the number of columns and the number of rows of the sub-column.

[0096] Please continue to refer to this. Figure 5 Step S302: Rotate and mirror the original two-dimensional matrix to obtain the rotation matrix information and mirror matrix information of the smallest repeating unit. The information of the smallest repeating unit graphic includes the original matrix information, rotation matrix information and mirror matrix information.

[0097] In this embodiment, it is assumed that the original two-dimensional matrix is ​​m rows × n columns, and the rotation matrix information includes any element A in the original m × n matrix. ij The coordinates of a 90° rotation are (j, mi-1); the coordinates of a 180° rotation are (mi-1, nj-1); and the coordinates of a 270° rotation are (nj-1, i).

[0098] Please refer to Figures 15 to 18 , Figure 15 It is a two-dimensional original matrix. Figure 16 for Figure 15 The two-dimensional original matrix in the image is rotated 90° clockwise. Figure 17 for Figure 15 The two-dimensional original matrix in the image is rotated 180° clockwise. Figure 18 for Figure 15 The two-dimensional original matrix is ​​rotated 270° clockwise.

[0099] The mirror matrix information includes: any element A in the original m×n matrix. ij The horizontally mirrored coordinates are (i, n-j+1); the vertically mirrored coordinates are (m-i+1, j).

[0100] Please refer to Figure 15 , Figure 19 and Figure 20 , Figure 19 for Figure 15 The vertical mirror image of the original two-dimensional matrix in the image. Figure 20 for Figure 15 The horizontal mirror of the two-dimensional original matrix in the image.

[0101] Please continue to refer to this. Figure 3Before executing step S40, step S70 is also included: determining whether the smallest repeating unit graphic is located at the boundary of the special unit structure region.

[0102] If the minimum repeating unit pattern is not located at the boundary of the special unit structure region, then the unit correction pattern corresponding to the minimum repeating unit pattern is obtained according to the first correction layout.

[0103] Please refer to Figure 7 In this embodiment, the method for determining whether the smallest repeating unit graphic is located at the boundary of a special unit structure region includes:

[0104] Step S701: Using any endpoint of the side length of the smallest repeating unit graphic as the second vertex, extend the region by a preset length along the mutually perpendicular first and second directions to obtain the extended region. The selection rule for the second vertex is the same as the selection rule for the first vertex.

[0105] Step S702: Using the smallest repeating unit graphic as the center, obtain the number of second vertices around the smallest repeating unit graphic in the extended region;

[0106] Step S703: If the number of second vertices around the smallest repeating unit graphic in the extended region is greater than or equal to 4, then it is determined that the smallest repeating unit graphic is not located at the boundary of the special unit structure region.

[0107] Step S704: If the number of second vertices around the smallest repeating unit graphic in the extended region is less than 4, then it is determined that the smallest repeating unit graphic is at the boundary of the special unit structure region.

[0108] Please refer to Figure 21 , Figure 21 To illustrate whether the minimum repeating unit graphic is located at the boundary of a special unit structure region, taking the minimum repeating unit region C as an example, the minimum repeating unit graphic is located within the minimum repeating unit region C. Taking any endpoint B of the side length of the minimum repeating unit graphic as the second vertex, the extended region E is obtained by extending it along a preset length along a first perpendicular direction X and a second perpendicular direction Y. The number of second vertices around the minimum repeating unit region C in the extended region E is obtained with the minimum repeating unit region C as the center.

[0109] In this embodiment, the preset length range of the extension along the mutually perpendicular first direction X and second direction Y is 1-2 times the length or width of the smallest repeating unit region C.

[0110] Figure 21 In the diagram, B1 to B8 are all the second vertices.

[0111] Please continue to refer to this. Figure 3 Step S40: Obtain the first revised layout after the design layout is corrected. The first revised layout has a unit revised pattern corresponding to the smallest repeating unit pattern.

[0112] By performing optical proximity correction on the design layout, the first corrected layout can be obtained, and the unit correction pattern in the minimum repeating unit corresponds one-to-one with the minimum repeating unit pattern.

[0113] The method for obtaining the cell correction pattern corresponding to the minimum repeating cell pattern includes: obtaining the minimum repeating cell pattern according to a special cell structure database; and obtaining the cell correction pattern corresponding to the minimum repeating cell pattern according to the first correction layout.

[0114] Please continue to refer to this. Figure 3 Step S50: Establish a database of special unit correction results based on the information of several unit correction graphics.

[0115] The information of the unit correction graphic includes the correspondence with the smallest repeating unit graphic.

[0116] Please continue to refer to this. Figure 3 Step S60: Establish a total database of special units based on the special unit structure database and the special unit correction result database, and in the total database of special units, the information of each minimum repeating unit graphic and the information of each unit correction graphic correspond one-to-one.

[0117] The special cell database includes information from the special cell structure database and the special cell correction result database, with a one-to-one correspondence between the information of each minimum repeating cell graphic and the information of each cell correction graphic. Therefore, when correcting the layout to be corrected, only the area to be corrected can be corrected, and the correction results for the special cell structure area to be corrected can be directly obtained from the special cell database, thus saving computation time for optical proximity correction.

[0118] Accordingly, embodiments of the present invention also provide, as shown in the example below. Figures 3 to 7 The special unit database established by the method.

[0119] Figure 8 This is a flowchart of the graphic correction method in an embodiment of the present invention.

[0120] Please refer to Figure 8 The graphic correction method includes:

[0121] Step S1: Provide a layout to be corrected, the layout to be corrected including the region to be corrected and the special unit structure region to be corrected;

[0122] Step S2: Obtain the smallest repeating element pattern to be corrected in the special element structure region to be corrected;

[0123] Step S3: Provide, for example Figures 3 to 7 The established special unit master database;

[0124] Step S4: Obtain information about the cell correction pattern corresponding to the minimum repeating cell pattern to be corrected from the special cell database;

[0125] Step S5: Perform optical proximity correction on the area to be corrected to obtain information of the second corrected image;

[0126] Step S6: Obtain the corrected layout based on the information of the second corrected pattern and the information of the unit corrected pattern.

[0127] The special unit structure database and the special unit correction result database are used to obtain the special unit total database. The information of the smallest repeating unit graphic in the special unit total database corresponds one-to-one with the information of each unit correction graphic. When correcting the layout to be corrected, only the area to be corrected can be corrected. The correction result of the special unit structure area to be corrected can be directly obtained from the special unit total database, thereby saving the calculation time of optical proximity correction.

[0128] Next, each step will be analyzed and explained.

[0129] Please continue to refer to this. Figure 8 Step S1: Provide a layout to be corrected, which includes a region to be corrected and a special unit structure region to be corrected.

[0130] The special structural region to be corrected contains several repeating unit patterns to be corrected, such as storage cells of dynamic random access memory (SRAM) or pixel cells of pixel structure; the region to be corrected is a pattern region that needs to undergo optical proximity correction.

[0131] Please continue to refer to this. Figure 8 Step S2: Obtain the smallest repeating unit graphic to be corrected in the special unit structure region to be corrected.

[0132] For the process of obtaining the minimum repeating element pattern to be corrected in the special element structure region to be corrected, please refer to [reference needed]. Figure 2 The content described herein will not be repeated here.

[0133] Please continue to refer to this. Figure 8 Execute step S3: Provide, for example Figures 3 to 7 The established special unit general database.

[0134] Before obtaining the information of the unit correction graphic corresponding to the minimum repeating unit graphic to be corrected from the special unit total database, the method further includes step S7: determining whether the minimum repeating unit graphic to be corrected is located at the boundary of the special unit structure region to be corrected.

[0135] If the minimum repeating unit pattern to be corrected is not located at the boundary of the special unit structure region to be corrected, then the information of the unit correction pattern corresponding to the minimum repeating unit pattern to be corrected is subsequently obtained from the special unit database.

[0136] If the minimum repeating unit pattern to be corrected is located at the boundary of the special unit structure region to be corrected, then the minimum repeating unit pattern to be corrected at the boundary of the special unit structure region to be corrected needs to be corrected separately.

[0137] Determining whether the minimum repeating unit pattern to be corrected is located at the boundary of the special unit structure region to be corrected can improve the accuracy of optical proximity correction.

[0138] For a method to determine whether the minimum repeating unit pattern to be corrected is located at the boundary of the special unit structure region to be corrected, please refer to [reference needed]. Figure 7 This will not be elaborated upon here.

[0139] Please continue to refer to this. Figure 8 Step S4: Obtain information on the cell correction graphic corresponding to the minimum repeating cell graphic to be corrected from the special cell database.

[0140] In the special unit database, the information of the smallest repeating unit graphic corresponds one-to-one with the information of the unit correction graphic. The smallest repeating unit graphic to be corrected also has corresponding unit correction graphic information.

[0141] Please continue to refer to this. Figure 8 Step S5: Perform optical proximity correction on the area to be corrected to obtain information of the second corrected image.

[0142] Only the region to be corrected is corrected. The correction results for the special cell structure region to be corrected can be directly obtained from the special cell database, thereby saving the calculation time of optical proximity correction.

[0143] Please continue to refer to this. Figure 8 Step S6: Obtain the corrected layout based on the information of the second corrected graphic and the information of the unit corrected graphic.

[0144] The revised layout includes information about the second revised pattern after the region to be revised is corrected, and information about the unit revised pattern after the special unit structure region to be corrected is corrected.

[0145] In another embodiment, if the minimum repeating unit pattern to be corrected is located at the boundary of a special unit structure region, then optical proximity correction is performed on the minimum repeating unit pattern at the boundary to obtain information of the third corrected pattern; and the corrected layout is obtained based on the information of the second corrected pattern, the unit corrected pattern information, and the information of the third corrected pattern.

[0146] Individually correcting the smallest repeating unit pattern to be corrected at the boundary of a special unit structure region can improve the accuracy of optical proximity correction.

[0147] 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 establishing a special unit total database for graphic correction, characterized in that, include: A design layout is provided, which includes several special unit structure regions, and the special unit structure regions include several graphics. Obtaining the minimum repeating unit graphic in a special unit structure region includes: selecting a feature graphic according to preset conditions; obtaining a feature vector of the feature graphic; obtaining a graphic that conforms to the feature vector in the design layout according to the feature vector; taking any endpoint of the side length of the feature graphic as a first vertex, extending it along a preset length along a first direction and a second direction that are perpendicular to each other to obtain the minimum repeating unit region, wherein the shape of the minimum repeating unit region is a rectangle, and the graphic in the minimum repeating unit region is the minimum repeating unit graphic; A special unit structure database is established based on the information of the minimum repeating unit graphic. Obtain the first revised layout after the design layout is corrected. The first revised layout has a unit revised pattern corresponding to the smallest repeating unit pattern. A database of special unit correction results is established based on information from several unit correction graphics. A general database of special units is established based on the special unit structure database and the special unit correction result database, and in the general database of special units, the information of each smallest repeating unit graphic and the information of each unit correction graphic correspond one-to-one.

2. The method for establishing a special unit total database for graphic correction as described in claim 1, characterized in that, The preset conditions include: the number of side lengths of the feature graphics is greater than or equal to 6.

3. The method for establishing a special unit total database for graphic correction as described in claim 1, characterized in that, The parameters of the feature vector include one or a combination of several of the following: area of ​​the figure, number of vertices, effective side length, and included angle of the sides.

4. The method for establishing a special unit total database for graphic correction as described in claim 1, characterized in that, The information of the smallest repeating unit graphic includes the original matrix information, rotation matrix information, and mirror matrix information.

5. The method for establishing a special unit total database for graphic correction as described in claim 4, characterized in that, The method for obtaining information about the smallest repeating unit graphic in a special unit structure region includes: converting the smallest repeating unit graphic into a two-dimensional original matrix and obtaining the original matrix information of the smallest repeating unit; rotating and mirroring the two-dimensional original matrix to obtain the rotation matrix information and mirror matrix information of the smallest repeating unit.

6. The method for establishing a special unit total database for graphic correction as described in claim 5, characterized in that, The method for converting the minimum repeating unit graphic into a two-dimensional original matrix includes: obtaining the minimum covering area of ​​the minimum repeating unit graphic, wherein the shape of the minimum covering area is rectangular; using each vertex of the minimum repeating unit graphic as a fixed point, extending along a first direction and a second direction to the boundary of the minimum repeating unit graphic to construct grid cells; according to the filling status of the grid cells, each empty grid cell is replaced with 0, and each fully filled grid cell is replaced with 1, to obtain an initial original matrix represented by 0 and 1, wherein each grid cell of the initial original matrix has a row height and a column width; obtaining the cell value according to the row height and column width of each cell of the initial original matrix, to obtain the two-dimensional original matrix.

7. The method for establishing a special unit total database for graphic correction as described in claim 6, characterized in that, The original two-dimensional matrix is ​​m rows × n columns, and the rotation matrix information includes: any element A in the original m × n matrix. ij The coordinates of a 90° rotation are (j, mi-1), the coordinates of a 180° rotation are (mi-1, nj-1), and the coordinates of a 270° rotation are (nj-1, i); the mirror matrix information includes any element A in the original m×n matrix. ij The horizontally mirrored coordinates are (i, n-j+1), and the vertically mirrored coordinates are (m-i+1, j).

8. The method for establishing a special unit total database for graphic correction as described in claim 6, characterized in that, The calculation method for the row height and column width of the grid cells of the initial original matrix is ​​as follows: the minimum coverage area is uniformly divided into several sub-columns along the first direction, and some sub-column lines coincide with the outline of the minimum repeating unit graphic in the second direction; the minimum coverage area is uniformly divided into several sub-rows along the second direction Y, and some sub-row lines coincide with the outline of the minimum repeating unit graphic in the first direction. Calculate the number of columns of the sub-columns of each grid cell in the first direction, and obtain the row height of the grid cell; Calculate the number of sub-rows of each grid cell in the second direction, and obtain the column width of the grid cell.

9. The method for establishing a special unit total database for graphic correction as described in claim 8, characterized in that, The two adjacent contour lines of the smallest repeating unit graphic are perpendicular to each other.

10. The method for establishing a special unit total database for graphic correction as described in claim 8, characterized in that, The angle between two adjacent contour lines of the smallest repeating unit graphic is an obtuse angle or an acute angle, and some of the grid cells are partially filled; the area of ​​the filled part is the value of the two-dimensional original matrix of the partially filled grid cell.

11. The method for establishing a special unit total database for graphic correction as described in claim 10, characterized in that, The method for obtaining the area of ​​the filled portion includes: obtaining the number of columns and the number of rows of the sub-column corresponding to the partially filled grid cell; and calculating the area of ​​the filled portion of the partially filled grid cell based on the number of columns and the number of rows of the sub-column.

12. The method for establishing a special unit total database for graphic correction as described in claim 1, characterized in that, The method for obtaining the cell correction pattern corresponding to the minimum repeating cell pattern includes: obtaining the minimum repeating cell pattern according to a special cell structure database; and obtaining the cell correction pattern corresponding to the minimum repeating cell pattern according to the first correction layout.

13. The method for establishing a special unit total database for graphic correction as described in claim 12, characterized in that, Before obtaining the cell correction pattern corresponding to the minimum repeating cell pattern according to the first correction layout, the method further includes: determining whether the minimum repeating cell pattern is located at the boundary of a special cell structure region; if the minimum repeating cell pattern is not located at the boundary of a special cell structure region, then obtaining the cell correction pattern corresponding to the minimum repeating cell pattern according to the first correction layout.

14. The method for establishing a special unit total database for graphic correction as described in claim 13, characterized in that, The method for determining whether the minimum repeating unit graphic is located at the boundary of a special unit structure region includes: taking any endpoint of the side length of the minimum repeating unit graphic as a second vertex, extending it by a preset length along a first direction and a second direction that are perpendicular to each other to obtain an extended region, wherein the selection rule for the second vertex is the same as the selection rule for the first vertex; taking the minimum repeating unit graphic as the center, obtaining the number of second vertices around the minimum repeating unit graphic in the extended region; if the number of second vertices around the minimum repeating unit graphic in the extended region is greater than or equal to 4, then it is determined that the minimum repeating unit graphic is not located at the boundary of a special unit structure region; if the number of second vertices around the minimum repeating unit graphic in the extended region is less than 4, then it is determined that the minimum repeating unit graphic is located at the boundary of a special unit structure region.

15. A special unit total database established using the method described in any one of claims 1 to 14.

16. A method for correcting graphics, characterized in that, include: A layout to be corrected is provided, the layout to be corrected including a region to be corrected and a special unit structure region to be corrected; Obtain the smallest repeating element graphic of the special element structure region to be corrected; Provide a special unit total database established by any one of claims 1 to 14; Retrieve information about the cell correction pattern corresponding to the minimum repeating cell pattern to be corrected from the special cell database; Optical proximity correction is performed on the area to be corrected to obtain information of the second corrected image; The corrected layout is obtained based on the information of the second corrected graphic and the information of the unit corrected graphic.

17. The graphic correction method as described in claim 16, characterized in that, Before obtaining the information of the cell correction pattern corresponding to the minimum repeating cell pattern to be corrected from the special cell database, the method further includes: determining whether the minimum repeating cell pattern to be corrected is located at the boundary of the special cell structure region to be corrected.

18. The graphic correction method as described in claim 16, characterized in that, If the minimum repeating unit pattern to be corrected is not located at the boundary of the special unit structure region to be corrected, then the corrected layout is obtained based on the information of the second corrected pattern and the information of the unit corrected pattern.

19. The graphic correction method as described in claim 17, characterized in that, If the minimum repeating unit pattern to be corrected is located at the boundary of the special unit structure region to be corrected, then optical proximity correction is performed on the minimum repeating unit pattern to be corrected at the boundary to obtain information of the third corrected pattern. The corrected layout is obtained based on the information of the second corrected graphic, the information of the unit corrected graphic, and the information of the third corrected graphic.

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