Target graph compensation method and device, storage medium and electronic equipment

Abstract

The invention discloses a target graph compensation method and device, a storage medium and electronic equipment. The method comprises the following steps: determining a fitting window; the number of the fitting windows is more than two, and the sizes of the fitting windows are different; calculating graph densities under different fitting windows; obtaining a key size load effect compensation model corresponding to the feature region; the feature region is a region where the target graph is located; the fitting window is greater than or equal to the size of the feature region; calculating a key size load effect compensation value of the graph in the feature region by utilizing the obtained key size load effect compensation model and combining the graph density under each fitting window; and performing critical dimension load effect compensation on the target graph by using the calculated critical dimension load effect compensation value. By adopting the method, the accuracy of complex graph compensation can be improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a target pattern compensation method and device, a storage medium, and an electronic device. Background Art

[0002] In the technology nodes with smaller and smaller sizes, due to the limitation of equipment resolution or stricter requirements on graphics, the same layer of graphics may be split into multiple masks to define the graphics of different areas, which leads to drastic changes in the density of graphics in different areas on the same mask. This process will bring significant critical dimension (CD) loading effect in areas with large differences in pattern density. Even when using equipment at advanced technology nodes, this critical dimension loading effect is a long-range effect of tens to hundreds of microns.

[0003] The so-called critical dimension (CD) load effect is the load effect caused by the change of the critical dimension. The so-called load effect refers to the effect of the etching rate reduction or uneven distribution caused by the local etching gas consumption being greater than the supply.

[0004] The existence of critical dimension loading effect will cause relatively large pitch walking during patterning, which may affect the process window of subsequent layers, equipment reliability, etc. Therefore, critical dimension loading effect is an important issue that cannot be ignored and needs to be solved.

[0005] In order to reduce the impact of critical dimension load effect on graphics, the commonly used method is to design test graphics with different densities in advance to obtain a table of correspondence between graphic density and critical dimension load effect compensation value. In actual compensation, the graphic to be compensated is taken as the center, and the graphic density is calculated with a fixed-size window. Finally, based on the calculated graphic density, the corresponding critical dimension load effect compensation value is obtained by looking up the table.

[0006] The above compensation method has a good compensation effect when the mask has only a single pattern and only the pattern density has sparse and dense variations. However, the compensation effect is poor when the mask has complex patterns. Summary of the invention

[0007] The problem to be solved by the present invention is to improve the accuracy of compensating for complex graphics.

[0008] To solve the above problem, an embodiment of the present invention provides a target graphics compensation method, the method comprising:

[0009] Determine a fitting window; the number of the fitting windows is more than two, and the sizes of the fitting windows are different;

[0010] Calculating the graphic density under different fitting windows;

[0011] Acquire a critical size load effect compensation model corresponding to a characteristic region; the characteristic region is the region where the target graphic is located; the fitting window is greater than or equal to the size of the characteristic region;

[0012] Calculate the critical size load effect compensation value of the graphics in the feature area by using the acquired critical size load effect compensation model and combining the graphics density under each fitting window;

[0013] The calculated critical dimension load effect compensation value is used to perform critical dimension load effect compensation on the target pattern.

[0014] Optionally, determining the segmentation fitting window includes:

[0015] Measuring the critical size load effect values ​​of the reference graphics under different graphic densities and different environments, and obtaining a curve of the critical size load effect value of the reference graphics as the distance between the environmental image and the reference graphics changes;

[0016] According to the preset compensation accuracy, the load effect variation interval of the key dimension of the reference figure is divided to obtain more than two fitting windows.

[0017] Optionally, the calculating the graphic density under different fitting windows includes:

[0018] The density of the graphics within the feature area and the density of the environmental graphics around the feature area are calculated.

[0019] Optionally, the critical dimension load effect compensation model is established by the following method:

[0020] Determine the graphic density under different fitting windows, and assign a corresponding weight coefficient to the graphic density under each fitting window;

[0021] The least square method is used to regress the weight coefficients corresponding to all fitting windows to obtain the critical dimension load effect compensation model.

[0022] Optionally, after obtaining the critical dimension load effect compensation model, the obtained critical dimension load effect compensation model is verified, and the verified critical dimension load effect compensation model is used as the final critical dimension load effect compensation model.

[0023] Optionally, the critical dimension load effect compensation model corresponding to the j-th feature area is as follows:

[0024]

[0025] in, represents the critical dimension load effect compensation value; i represents the i-th fitting window, n represents the total number of i-th fitting windows in the mask; K i Indicates the weight coefficient corresponding to the i-th fitting window; Den i (self) represents the density of the graph in the jth feature area under the i-th fitting window; Den i (ref) represents the environmental pattern density around the jth feature area under the i-th fitting window; α represents Den i (ref) weight coefficient; β represents Den i The weight coefficient of (ref).

[0026] The embodiment of the present invention further provides a target graphics compensation device, the device comprising:

[0027] A window determination unit, adapted to determine a fitting window; the number of the fitting windows is more than two, and the sizes of the fitting windows are different;

[0028] A graphic density calculation unit, adapted to calculate the graphic density under different fitting windows;

[0029] A model acquisition unit, adapted to acquire a critical size load effect compensation model corresponding to a characteristic region; the characteristic region is a region where the target graphic is located; the fitting window is greater than or equal to the size of the characteristic region;

[0030] A compensation calculation unit, adapted to calculate a critical dimension load effect compensation value of the graphic in the feature area by using the acquired critical dimension load effect compensation model in combination with the graphic density under each of the fitting windows;

[0031] The compensation unit is adapted to perform critical dimension load effect compensation on the target pattern using the calculated critical dimension load effect compensation value.

[0032] Optionally, the window determination unit is suitable for measuring the key dimension load effect value of the reference graphic under different graphic densities and different environments, obtaining a curve of the key dimension load effect value of the reference graphic changing with the distance between the environmental image and the reference graphic, and dividing the key dimension load effect change interval of the reference graphic according to a preset compensation accuracy to obtain more than two fitting windows.

[0033] Optionally, the graphic density calculation unit is adapted to calculate the density of the graphics within the feature area and the density of environmental graphics around the feature area.

[0034] Optionally, the device also includes: a model building unit, which is suitable for determining the graphic density under different fitting windows, assigning a corresponding weight coefficient to the graphic density under each fitting window, and using the least squares method to regress the weight coefficients corresponding to all fitting windows to obtain the critical dimension load effect compensation model.

[0035] Optionally, the model building unit is further adapted to verify the obtained critical dimension load effect compensation model after obtaining the critical dimension load effect compensation model, and use the verified critical dimension load effect compensation model as the final critical dimension load effect compensation model.

[0036] An embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. The computer program is executed by a processor to implement the steps of any of the above methods.

[0037] An embodiment of the present invention further provides an electronic device, including a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and the processor executes the steps of any of the above methods when running the computer program.

[0038] Compared with the prior art, the technical solution of the embodiment of the present invention has the following advantages:

[0039] The scheme of the present invention is applied to determine more than two fitting windows, calculate the pattern density under different fitting windows, and then use the corresponding key size load effect compensation model in combination with the pattern density under each fitting window to compensate the target pattern. Since the sizes of different fitting windows are different, the pattern density obtained by using fitting windows of different sizes can reflect the influence of environmental patterns with different distances from the feature area pattern on the key size load effect of the feature area pattern, so that the feature area pattern can be compensated more accurately.

[0040] Furthermore, by calculating the density of the graphics in the feature area and the density of the environmental graphics around the feature area as the graphics density under the fitting window, since the density of the graphics in the feature area and the density of the environmental graphics around the feature area are considered separately, and the density of the environmental graphics around the feature area can reflect the influence of the environmental graphics itself on the key size load effect of the graphics in the feature area, in this way, the key size load effect compensation value is calculated based on these two factors: the distance from the feature area graphics and the environmental graphics itself, which can further improve the accuracy of compensating the feature area graphics. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 and Figure 2 A schematic diagram of two masks into which a graphic of the same layer is split;

[0042] Figure 3 It is a graphical schematic diagram of a mask having a single graphic;

[0043] Figure 4 It is a graphic schematic diagram of a mask with complex graphics;

[0044] Figure 5 yes Figure 2 A graphical schematic diagram of the local environment area around the lines in the middle area 20;

[0045] Figure 6 It is a curve diagram showing the influence of the distance between the environment graphic and the target graphic on the load effect of the key dimension of the target graphic;

[0046] Figure 7 is a flow chart of a target graphics compensation method in an embodiment of the present invention;

[0047] Figure 8 It is a curve diagram showing a change in a critical dimension load effect value of a reference pattern with a distance between an environment pattern and the reference pattern in an embodiment of the present invention;

[0048] Fig. 9 is a schematic diagram of a fitting window of different sizes in an embodiment of the present invention;

[0049] Fig.10 is a flow chart of a method for establishing a critical dimension load effect compensation model in an embodiment of the present invention;

[0050] Fig.11 It is a curve diagram showing the variation of the critical size load effect compensation value with the pattern density calculated by the fitting window of a single fixed size;

[0051] Fig.12 It is a curve diagram showing the variation of the critical size load effect compensation value with the pattern density calculated by the multi-size fitting window;

[0052] Fig.13 It is a schematic diagram of the error comparison between the critical dimension load effect compensation value calculated by using a fitting window of a single fixed size and the critical dimension load effect compensation value calculated by using a fitting window of multiple sizes and the actual measured value;

[0053] Fig.14 It is a structural schematic diagram of a target pattern compensation device in an embodiment of the present invention. DETAILED DESCRIPTION

[0054] Figure 1 and Figure 2 The figure is a schematic diagram of the same layer of graphics being split into two masks, each mask is used to define the graphics of different areas. Figure 1 The first photomask 10 shown has a plurality of lines 11 arranged in parallel. Figure 2 The second mask 20 shown has a plurality of parallel lines 21. The lines 11 and 21 are distributed in different areas. As a result, the pattern density of the first mask 10 and the second mask 20 in different areas changes dramatically, and when the pattern on the mask is transferred to the silicon wafer, the critical dimension of the pattern changes, thereby bringing about a significant critical dimension loading effect.

[0055] At more advanced technology nodes, there are very strict restrictions on the size changes of key structures in the front end of the line (FEOL). For example, in the fin and gate loop, if the self-aligned multiple patterning method is used, once the key size of the pattern changes, the key size load effect caused will cause a relatively large pitch walking during the patterning process, which may affect the process window and equipment reliability of the subsequent layers. Among them, the critical size here refers to the width of the pattern itself. The so-called pitch drift refers to the periodic structure of a certain layer of the chip pattern is not presented according to the design of the mask, but the individual patterns are moved.

[0056] In order to reduce the impact of critical dimension load effect on graphics, the commonly used method is to design test graphics with different densities in advance to obtain a table of correspondence between graphic density and critical dimension load effect compensation value. In actual compensation, the graphic to be compensated (hereinafter referred to as the target graphic) is taken as the center, and the graphic density is calculated with a fixed-size window. Finally, based on the calculated graphic density, the corresponding critical dimension load effect compensation value is obtained by looking up the table.

[0057] The above compensation method has a better compensation effect when there is only a single pattern on the mask and only the pattern density has sparse and dense changes. Figure 3 The mask 30 has a plurality of regions, namely, a first region 31, a second region 32, a third region 33, a fourth region 34, and a fifth region 35. The widths of the lines 310 in each region are the same, that is, the critical dimensions are the same. The density of the lines 300 in each region is different. The above method has a better effect of compensating the critical dimension load effect of the lines 310 in the mask 30.

[0058] However, in actual applications, there may be a variety of complex patterns on the mask, and the pattern width and density between patterns may vary. Figure 4The mask 40 has a plurality of regions, namely a first region 41, a second region 42, a third region 43, a fourth region 44 and a fifth region 45. The width of the line 410 in the first region 41 is smaller than the width of the line 420 in the second region 42. The pitch between adjacent lines 420 in the second region 42 is smaller than the pitch between adjacent lines 430 in the third region 43.

[0059] The inventors have found that, in the case of complex patterns on the mask, changes in the density of the ambient patterns around the target pattern have a long-range effect on the critical dimensions of the target pattern, and different ambient patterns around the target pattern contribute differently to the density of the target pattern.

[0060] by Figure 2 For example, the line 21 in the middle area 20 is the target graphic. Figure 1 and Figure 2 When forming a pattern on the same layer, Figure 1 Several lines 11 as Figure 2 The environmental graphics of the lines in the middle area 20, the schematic diagram of the local area graphics obtained is as follows Figure 5 shown.

[0061] Figure 6 The curve showing the influence of the distance between the environmental graphics and the target graphics on the load effect of the key size of the target graphics is shown. The inventors have found that as the distance D from the lines in the area 20 increases, the influence of the environmental graphics around the area 20 on the load effect of the key size in the area 20 becomes smaller and smaller, and the closer the environmental graphics are to the target graphics, the greater the influence on the load effect of the key size of the target graphics.

[0062] Therefore, the density of the environmental patterns around the target pattern and the environmental patterns themselves will affect the critical dimension load effect compensation value of the target pattern.

[0063] In view of this problem, the present invention provides a target graphic compensation method. The method is applied to determine more than two fitting windows, calculate the graphic density under different fitting windows, and then use the corresponding key size load effect compensation model in combination with the graphic density under each fitting window to compensate the target graphic. Since the sizes of different fitting windows are different, the graphic density obtained by using fitting windows of different sizes can reflect the influence of environmental graphics with different distances from the feature area graphics on the key size load effect of the feature area graphics, so that the feature area graphics can be compensated more accurately.

[0064] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0065] Reference Figure 7, an embodiment of the present invention provides a target graphics compensation method, the method may include the following steps:

[0066] Step 71, determining the fitting window.

[0067] There are more than two fitting windows, and the sizes of the fitting windows are different. The fitting windows are used for subsequent calculation of the graphic density required for fitting.

[0068] In order to enable the fitting window to more accurately reflect the influence of the surrounding environmental graphics at different distances on the key dimension load effect of the target graphic, in one embodiment of the present invention, by measuring the key dimension load effect value of the benchmark graphic under different graphic densities and different environments, a curve of the key dimension load effect value of the benchmark graphic changing with the distance between the environmental image and the benchmark graphic can be obtained, and then the key dimension load effect change interval of the benchmark graphic can be divided according to the preset compensation accuracy to obtain two or more fitting windows.

[0069] The so-called reference pattern is the reference pattern when making the mask. Each layer of the mask can be set with a reference pattern, and the pattern on the mask can be set with the reference pattern as a reference. The so-called critical dimension load effect variation range is from the stable and unchanged critical dimension load effect compensation value to the critical dimension load effect compensation maximum value.

[0070] According to the preset compensation accuracy, when dividing the critical dimension load effect change interval of the reference figure, assuming that the critical dimension load effect change interval is n (nm) and the required compensation accuracy is 1nm, the critical dimension load effect change interval can be divided with a step size of 1nm to obtain the corresponding n fitting windows.

[0071] For example, by measuring the critical dimension load effect value of the benchmark graphics under different graphics densities and different environments, the Figure 8 The scatter plot shown in Figure 8 Each point represents the critical dimension load effect value of the environmental figure at different distances from the reference figure. The obtained critical dimension load effect values ​​are fitted to obtain a curve 81 showing the critical dimension load effect value of the reference figure as the distance between the environmental figure and the reference figure changes.

[0072] After obtaining curve 81, the critical dimension load effect variation range is 3 nm, and 3 nm can be divided into steps of 1 nm to obtain three fitting windows, namely fitting window Win1, fitting window Win2 and fitting window Win3.

[0073] Step 72, calculating the pattern density under different fitting windows.

[0074] In the specific implementation, taking the i-th fitting window Wini as an example, the graphic density under the fitting window Wini is calculated, that is, the ratio of the area of ​​the mask to the area of ​​the fitting window Wini is calculated, that is, the number of fitting windows Wini in the mask, thereby obtaining the graphic density under each fitting window.

[0075] In one embodiment of the present invention, the pattern density under the fitting window includes the density of the pattern in the feature area and the density of the environmental pattern around the feature area. Taking the i-th fitting window Wini as an example, the density of the pattern in the feature area under the fitting window Wini is the ratio of the area of ​​the pattern in the feature area in the mask to the area of ​​the fitting window Wini. The environmental pattern density under the fitting window Wini is the ratio of the area of ​​the environmental pattern in the mask to the area of ​​the fitting window Wini.

[0076] Since different environmental graphics have different effects on the graphics in the feature area, by distinguishing the density of the graphics in the feature area and the density of the environmental graphics around the feature area, when calculating the graphic density under the fitting window, the influence of the environmental graphics itself on the graphics in the feature area can be combined, thereby obtaining a more accurate critical dimension load effect compensation value.

[0077] Step 73, obtaining a critical dimension load effect compensation model corresponding to the feature area.

[0078] The characteristic region is the region where the target graphic is located; and the fitting window is larger than or equal to the size of the characteristic region.

[0079] Reference Fig. 9 , the sizes of the fitting window Win1, the fitting window Win2 and the fitting window Win3 are different, and are all larger than the size of the feature region 91. Thus, the graphics in the feature region 91 and the graphics in the environment region 92 outside the feature region 91 can be included in at least the fitting window, so that when compensating the target graphics according to the fitting window, the distance between the environment graphics and the target graphics is taken into account, thereby improving the accuracy of compensation.

[0080] In some embodiments, the size of one of the fitting windows may also be equal to the size of the feature region 91 .

[0081] In an embodiment of the present invention, each feature region corresponds to a critical dimension load effect compensation model. The critical dimension load effect compensation models corresponding to two feature regions may be the same or different, and there is no limitation here. For any target graphic, the feature region where it is located can be determined. When performing critical dimension load effect compensation on the target graphic, the critical dimension load effect compensation model of the feature region where it is located can be used to perform critical dimension load effect compensation.

[0082] In one embodiment of the present invention, assuming that the target pattern is in the jth feature region of the mask, the critical dimension load effect compensation model corresponding to the jth feature region is as follows:

[0083]

[0084] in, represents the critical dimension load effect compensation value; i represents the i-th fitting window, n represents the total number of i-th fitting windows in the mask; K i Indicates the weight coefficient corresponding to the i-th fitting window; Den i Represents the graphic density under the i-th fitting window.

[0085] In one embodiment of the present invention, assuming that the target pattern is in the jth feature region of the mask, the critical dimension load effect compensation model corresponding to the jth feature region is as follows:

[0086]

[0087] in, represents the critical dimension load effect compensation value; i represents the i-th fitting window, n represents the total number of i-th fitting windows in the mask; K i Indicates the weight coefficient corresponding to the i-th fitting window; Den i (self) represents the density of the graph in the jth feature area under the i-th fitting window; Den i (ref) represents the environmental graphic density around the jth feature area under the ith fitting window; α represents the weight coefficient of the graphic density in the jth feature area; β represents the weight coefficient of the environmental graphic density in the jth feature area.

[0088] Step 74 , using the acquired critical dimension load effect compensation model and combining the pattern density under each of the fitting windows, calculate the critical dimension load effect compensation value of the pattern in the feature area.

[0089] In one embodiment of the present invention, when formula (1) is used as the critical size load effect compensation model corresponding to the jth feature area, the weight coefficient corresponding to each fitting window can be determined. After obtaining the pattern density under the i-th fitting window, it is substituted into formula (1) to obtain the critical size load effect compensation value of the j-th feature area.

[0090] Using the above formula (1), the load effect compensation value of the key dimension of the jth feature area is calculated as Since the influence of the distance between the environment pattern and the pattern in the feature area on the critical dimension load effect of the pattern in the feature area is taken into consideration, a more accurate critical dimension load effect value can be obtained.

[0091] In another embodiment of the present invention, when formula (2) is used as the critical dimension load effect compensation model corresponding to the jth feature area, the weight coefficients corresponding to each fitting window, the weight coefficient of the pattern density in the jth feature area, and the weight coefficient of the ambient pattern density in the jth feature area can be determined. i (self) and the environmental graphic density Den around the jth feature area under the i-th fitting window i (ref) is then substituted into formula (2) to obtain the load effect compensation value of the key dimension of the jth feature area:

[0092] Using the above formula (2), the load effect compensation value of the key dimension of the jth feature area is calculated as Since the distance between the environmental pattern and the pattern in the feature area and the influence of the environmental pattern itself on the critical dimension load effect of the pattern in the feature area are taken into consideration at the same time, a more accurate critical dimension load effect value can be obtained.

[0093] Step 75, using the calculated critical dimension load effect compensation value, perform critical dimension load effect compensation on the target pattern.

[0094] In a specific implementation, the edge of the target pattern is offset by using the calculated critical dimension load effect compensation value to achieve critical dimension load effect compensation for the target pattern, thereby obtaining a compensated target pattern, which can then be used to make a mask.

[0095] In order to enable those skilled in the art to better understand and implement the present invention, the embodiment of the present invention also provides a method for establishing a critical size load effect compensation model, referring to Fig.10 , the method may include the following steps:

[0096] Step 101, determining the graphic density under different fitting windows, and assigning a corresponding weight coefficient to the graphic density under each fitting window.

[0097] In a specific implementation, the following steps may be used to determine the graphic density under different fitting windows:

[0098] Step 101a: measuring the critical dimension load effect values ​​of the reference pattern under different pattern densities and different environments, and obtaining a curve of the critical dimension load effect value of the reference pattern changing with the distance between the environment image and the reference pattern.

[0099] Step 101b, dividing the critical dimension load effect variation interval of the reference pattern according to the preset compensation accuracy to obtain more than two fitting windows, and assigning a weight coefficient to the pattern density of each fitting window.

[0100] In the specific implementation, taking the i-th fitting window Wini as an example, the weight coefficient of the fitting window Wini is K i , the graphic density is Den i The sum of the weight coefficients of the graphic density corresponding to each fitting window is 1, that is, K1+K2+…+K n =1.

[0101] At this time, the relationship between the critical size load effect compensation value corresponding to the jth feature area and the pattern density can be expressed as follows:

[0102]

[0103] In an embodiment of the present invention, the graphic densities under different fitting windows may include: the density of the graphic in the feature area under the fitting window and the density of the environmental graphic around the feature area.

[0104] At this time, the method for determining the graphic density under different fitting windows may also include:

[0105] Step 101c: Calculate the density of the graphics in the feature area and the density of the environmental graphics around the feature area under different fitting windows, and assign corresponding weight coefficients to the density of the graphics in the feature area and the density of the environmental graphics around the feature area.

[0106] The graphic density of the i-th fitting window Wini is Den i It can be expressed as:

[0107] Den i =α*Den i (self)+β*Den i (ref) (4)

[0108] Among them, Den i (self) represents the density of the graph in the jth feature area under the i-th fitting window; Den i (ref) represents the environmental graphic density around the jth feature area under the ith fitting window; α represents the weight coefficient of the graphic density in the jth feature area; β represents the weight coefficient of the environmental graphic density in the jth feature area.

[0109] At this time, the relationship between the critical dimension load effect compensation value corresponding to the j-th feature area and the pattern density is shown in formula (2).

[0110] Step 102: using the least square method, regressing the weight coefficients corresponding to all fitting windows to obtain the critical dimension load effect compensation model.

[0111] In a specific implementation, the weight coefficient K of the graphic density under each fitting window can be pre-set. i , and the weight coefficient α of the graphic density in the feature area and the weight coefficient β of the environmental graphic density, respectively set a value space, and then use the least squares method to traverse the value space to calculate the key size load effect compensation value under each value combination And calculate the actual measured value L of the critical dimension load effect j and compensation value The actual measured value L j and compensation value The compensation value when the sum of squares of the differences is minimized The corresponding weight coefficient K i , α and β are substituted into formula (2) to obtain the corresponding critical dimension load effect compensation model.

[0112] In some embodiments, when formula (1) is used as the critical dimension load effect compensation model corresponding to the jth feature area, the weight coefficient K can also be obtained by the least squares method. i , thus obtaining the corresponding critical dimension load effect compensation model.

[0113] In one embodiment of the present invention, the method may further include:

[0114] Step 103 , verifying the obtained critical dimension load effect compensation model.

[0115] In a specific implementation, since the test pattern has a strong symmetry, in order to further improve the accuracy of the critical dimension load effect compensation model, the critical dimension load effect compensation model obtained in step 102 can be used to predict the critical dimension load effect compensation value of the actual design pattern, and the predicted compensation value is compared with the actual measured value. When the difference between the two meets the preset threshold requirement, it indicates that the critical dimension load effect compensation model obtained in step 102 has passed the verification.

[0116] When the verification fails, it indicates that the critical dimension load effect compensation model obtained in step 102 fails to be verified, and step 101b is re-executed until a critical dimension load effect compensation model that can pass the verification is obtained.

[0117] Fig.11 The middle curve 100 represents the variation of the critical dimension loading effect compensation value with the pattern density calculated by a single fixed size fitting window. Fig.11The scattered points in the figure are the actual measured values ​​corresponding to different graphic densities. Fig.11 It can be seen that the critical dimension load effect compensation value determined by the pattern density calculated based on the fitting window of a single fixed size has a large deviation from the actual measured value and a low correlation.

[0118] Fig.12 The middle curve 200 represents a curve showing how the critical dimension load effect compensation value varies with the pattern density calculated by the fitting window of multiple sizes. Fig.12 The scattered points in the figure are the actual measured values ​​corresponding to different graphic densities. Fig.12 It can be seen that the critical dimension load effect compensation value determined by the pattern density calculated based on the multi-size fitting window is more convergent and more correlated with the actual measurement value.

[0119] Fig.13 This is a schematic diagram showing the error comparison between the critical dimension load effect compensation value calculated using a single fixed-size fitting window and the critical dimension load effect compensation value calculated using a multi-size fitting window and the actual measured value. Fig.13 , the error between the critical dimension load effect compensation value calculated by a single fixed-size fitting window and the actual measured value is 1.69, and the error between the critical dimension load effect compensation value calculated by a multi-size fitting window and the actual measured value is 0.74. Obviously, the critical dimension load effect compensation value calculated by a multi-size fitting window is closer to the actual measured value, that is, the compensation value is more accurate.

[0120] That is to say, compared with the existing critical dimension load effect compensation value solution using a single fixed-size fitting window for calculation, the critical dimension load effect compensation model in the embodiment of the present invention can more accurately compensate for the critical dimension of the target graphic.

[0121] From the above content, it can be seen that the method for establishing the key dimension load effect compensation model in the embodiment of the present invention provides a multiple linear regression model based on the two aspects that the key dimension load effect compensation value will change with the distance from the feature area graphic and the difference in the environmental graphic. The least squares method is used to obtain the graphic density weight under each fitting window, the weight coefficient of the density of the feature area graphic itself, and the weight coefficient of the environmental graphic density. Finally, the deviation between the key dimension load effect compensation value predicted by the new model and the actual measured value is smaller, and the compensation is more accurate.

[0122] The critical dimension load effect compensation model in the embodiment of the present invention is more suitable for complex graphics with multiple critical dimensions and spacing combinations, as well as key layers in complex environments with more positional relationships, and can be applied to more advanced technology nodes.

[0123] In order to enable those skilled in the art to better understand and implement the present invention, the target graphic compensation device and computer-readable storage medium corresponding to the above method are described in detail below.

[0124] Reference Fig.14 The embodiment of the present invention provides a target graphics compensation device 140, which may include: a window determination unit 141, a graphics density calculation unit 142, a model acquisition unit 143, a compensation calculation unit 144 and a compensation unit 145. Among them:

[0125] The window determination unit 141 is adapted to determine a fitting window; there are more than two fitting windows, and the sizes of the fitting windows are different;

[0126] The graphic density calculation unit 142 is adapted to calculate the graphic density under different fitting windows;

[0127] The model acquisition unit 143 is adapted to acquire a critical size load effect compensation model corresponding to a characteristic region; the characteristic region is the region where the target graphic is located; the fitting window is greater than or equal to the size of the characteristic region;

[0128] The compensation calculation unit 144 is adapted to calculate the critical dimension load effect compensation value of the graphic in the feature area by using the acquired critical dimension load effect compensation model in combination with the graphic density under each of the fitting windows;

[0129] The compensation unit 145 is adapted to use the calculated critical size load effect compensation value to perform critical size load effect compensation on the target graphic.

[0130] In one embodiment of the present invention, the window determination unit 141 is suitable for measuring the critical dimension load effect value of the reference graphic under different graphic densities and different environments, obtaining a curve of the critical dimension load effect value of the reference graphic changing with the distance between the environmental image and the reference graphic, and dividing the critical dimension load effect change interval of the reference graphic according to a preset compensation accuracy to obtain more than two fitting windows.

[0131] In one embodiment of the present invention, the graphic density calculation unit 142 is adapted to calculate the density of the graphic within the feature area and the density of the environmental graphic around the feature area.

[0132] In one embodiment of the present invention, the device 140 may also include: a model building unit 146, wherein the model building unit 146 is suitable for determining the graphic density under different fitting windows, assigning a corresponding weight coefficient to the graphic density under each fitting window, and using the least squares method to regress the weight coefficients corresponding to all fitting windows to obtain the critical dimension load effect compensation model.

[0133] In one embodiment of the present invention, the model building unit 146 is further suitable for verifying the obtained critical dimension load effect compensation model after obtaining the critical dimension load effect compensation model, and using the verified critical dimension load effect compensation model as the final critical dimension load effect compensation model.

[0134] An embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is run, the steps of any one of the methods described in the above embodiments are executed, which will not be described in detail.

[0135] In a specific implementation, the computer-readable storage medium may include: ROM, RAM, magnetic disk or optical disk, etc.

[0136] An embodiment of the present invention also provides an electronic device, wherein the terminal may include a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor runs the computer instructions, the steps of the control method of the electronic device in any one of the above embodiments are executed, which will not be repeated here.

[0137] Regarding the various modules / units included in the various devices and products described in the above embodiments, they can be software modules / units, or hardware modules / units, or they can be partially software modules / units and partially hardware modules / units. For example, for various devices and products applied to or integrated in a chip, the various modules / units included therein can all be implemented in the form of hardware such as circuits, or at least some of the modules / units can be implemented in the form of software programs, which run on a processor integrated inside the chip, and the remaining (if any) modules / units can be implemented in the form of hardware such as circuits; for various devices and products applied to or integrated in a chip module, the various modules / units included therein can all be implemented in the form of hardware such as circuits, and different modules / units can be located in the same component (such as a chip, circuit module, etc.) or different components of the chip module, or at least some of the modules / units can be implemented in the form of hardware such as circuits. The element can be implemented in the form of a software program, which runs on a processor integrated inside the chip module, and the remaining (if any) modules / units can be implemented in the form of hardware such as circuits; for various devices and products applied to or integrated in the terminal, the various modules / units contained therein can be implemented in the form of hardware such as circuits, and different modules / units can be located in the same component (for example, chip, circuit module, etc.) or in different components in the terminal, or, at least some modules / units can be implemented in the form of a software program, which runs on a processor integrated inside the terminal, and the remaining (if any) modules / units can be implemented in the form of hardware such as circuits.

[0138] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A target graphics compensation method, characterized in that: include: Determine a fitting window; the number of the fitting windows is more than two, and the sizes of the fitting windows are different; Calculating the graphic density under different fitting windows; Acquire a critical size load effect compensation model corresponding to a characteristic region; the characteristic region is the region where the target graphic is located; the fitting window is greater than or equal to the size of the characteristic region; Calculate the critical size load effect compensation value of the graphics in the feature area by using the acquired critical size load effect compensation model and combining the graphics density under each fitting window; The calculated critical dimension load effect compensation value is used to perform critical dimension load effect compensation on the target pattern.

2. The target pattern compensation method according to claim 1, characterized in that: The step of determining the segmentation fitting window comprises: Measuring the critical size load effect values ​​of the reference graphics under different graphic densities and different environments, and obtaining a curve of the critical size load effect value of the reference graphics as the distance between the environmental image and the reference graphics changes; According to the preset compensation accuracy, the load effect variation interval of the key dimension of the reference figure is divided to obtain more than two fitting windows.

3. The target pattern compensation method according to claim 1, characterized in that: The calculating of the graphic density under different fitting windows includes: The density of the graphics within the feature area and the density of the environmental graphics around the feature area are calculated.

4. The target pattern compensation method according to claim 1, characterized in that: The critical dimension load effect compensation model is established by the following method: Determine the graphic density under different fitting windows, and assign a corresponding weight coefficient to the graphic density under each fitting window; The least square method is used to regress the weight coefficients corresponding to all fitting windows to obtain the critical dimension load effect compensation model.

5. The target pattern compensation method according to claim 4, characterized in that: After the critical dimension load effect compensation model is obtained, the obtained critical dimension load effect compensation model is verified, and the verified critical dimension load effect compensation model is used as the final critical dimension load effect compensation model.

6. The target pattern compensation method according to claim 1, characterized in that: The critical dimension load effect compensation model corresponding to the jth feature area is as follows: in, represents the critical dimension load effect compensation value; i represents the i-th fitting window, n represents the total number of i-th fitting windows in the mask; K i Represents the weight coefficient corresponding to the i-th fitting window; Den i (self) represents the density of the graph in the jth feature area under the i-th fitting window; Den i (ref) represents the environmental pattern density around the jth feature area under the i-th fitting window; α represents Den i (ref) weight coefficient; β represents Den i The weight coefficient of (ref).

7. A target pattern compensation device, characterized in that: include: A window determination unit, adapted to determine a fitting window; the number of the fitting windows is more than two, and the sizes of the fitting windows are different; A graphic density calculation unit, adapted to calculate the graphic density under different fitting windows; A model acquisition unit, adapted to acquire a critical size load effect compensation model corresponding to a characteristic region; the characteristic region is a region where the target graphic is located; the fitting window is greater than or equal to the size of the characteristic region; A compensation calculation unit, adapted to calculate a critical dimension load effect compensation value of the graphic in the feature area by using the acquired critical dimension load effect compensation model in combination with the graphic density under each of the fitting windows; The compensation unit is adapted to perform critical dimension load effect compensation on the target pattern using the calculated critical dimension load effect compensation value.

8. The target pattern compensation device according to claim 7, characterized in that: The window determination unit is suitable for measuring the critical dimension load effect value of the reference graphic under different graphic densities and different environments, obtaining a curve of the critical dimension load effect value of the reference graphic as the distance between the environmental image and the reference graphic changes, and dividing the critical dimension load effect change interval of the reference graphic according to a preset compensation accuracy to obtain more than two fitting windows.

9. The target pattern compensation device according to claim 7, characterized in that: The graphic density calculation unit is adapted to calculate the density of the graphic in the feature area and the density of the environmental graphic around the feature area.

10. The target pattern compensation device according to claim 7, characterized in that: It also includes: a model building unit, which is suitable for determining the graphic density under different fitting windows, assigning a corresponding weight coefficient to the graphic density under each fitting window, and using the least squares method to regress the weight coefficients corresponding to all fitting windows to obtain the critical dimension load effect compensation model.

11. The target pattern compensation device according to claim 10, characterized in that: The model building unit is also suitable for verifying the obtained critical dimension load effect compensation model after obtaining the critical dimension load effect compensation model, and using the verified critical dimension load effect compensation model as the final critical dimension load effect compensation model.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer program is executed by a processor to implement the steps of the method according to any one of claims 1 to 6.

13. An electronic device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, wherein: When the processor runs the computer program, the steps of the method according to any one of claims 1 to 6 are performed.

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