OPC result verification method, device, equipment and storage medium

Abstract

The present application discloses an OPC result verification method, device, equipment and storage medium, which relates to the field of optical correction technology of microelectronic layout data, including: obtaining a photolithography pattern after OPC correction; detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern, and obtaining the image logarithmic slope of the photolithography pattern at the edge position; respectively judging whether the image logarithmic slope at each edge position is less than a preset slope threshold or is located in a preset slope interval; if the image logarithmic slope is less than the preset slope threshold or is located in the preset slope interval, then marking a defect at the corresponding edge position of the photolithography pattern, and judging that the OPC verification result of the photolithography pattern is failed. The present application can solve the random effect of photoresist and improve the yield of photolithography chips.

Description

Technical Field

[0001] The present application relates to the technical field of optical correction of microelectronic layout data, and in particular to an OPC result verification method, device, equipment and storage medium. Background Art

[0002] At present, in the publication process of semiconductor manufacturing masks, OPC (Optical Proximity Correction) technology has been widely used. The most widely used OPC method is a method based on a model to correct the optical proximity effect. Specifically, the potential imaging error of the lithography process is obtained through simulation calculation of the OPC model, and the target graphic is pre-corrected based on the error to compensate for the graphic distortion or deformation caused by the optical proximity effect.

[0003] As the technology node advances, the feature size of semiconductor manufacturing continues to shrink, and the precision requirements for lithography imaging are getting higher and higher, which requires that the OPC correction accuracy must meet the process requirements. At present, in the model-based OPC method, OPC verification has become an indispensable step in the OPC processing flow. Its basic principle is to globally simulate the mask pattern (that is, the pattern after OPC correction) and check whether there are process hotspots to determine whether the OPC correction is correct.

[0004] However, during OPC correction, the random effect of photoresist will cause the width of the process variation band (PV band) to increase. In some cases, this increase may lead to process failure. Therefore, in OPC correction, how to overcome the random effect of photoresist and improve the yield of photolithography chips is a problem that needs to be further solved in this field. Summary of the invention

[0005] In view of this, the purpose of this application is to provide an OPC result verification method, device, equipment and storage medium, which can solve the random effect of photoresist and improve the yield of photolithography chips. The specific scheme is as follows:

[0006] In a first aspect, the present application discloses an OPC result verification method, comprising:

[0007] Obtaining the OPC-corrected lithography pattern;

[0008] Detecting the influence of exposure intensity on the characteristic size of the photolithography pattern, and obtaining the image logarithmic slope of the photolithography pattern at the edge position;

[0009] Determine whether the image logarithmic slope at each edge position is less than a preset slope threshold or is within a preset slope range;

[0010] If the image logarithmic slope is less than the preset slope threshold or is within the preset slope range, a defect mark is performed at a corresponding edge position of the lithography pattern, and an OPC verification result of the lithography pattern is determined to be failed.

[0011] Optionally, the detecting the influence of the exposure intensity on the characteristic size of the lithography pattern to obtain the image logarithmic slope of the lithography pattern at the edge position includes:

[0012] Calculating the exposure intensity of the photolithography pattern at the edge position, the change gradient of the exposure intensity, and the change amount of the pattern size;

[0013] The influence of the exposure intensity on the characteristic size of the photolithography pattern is detected based on the exposure intensity, the change gradient and the pattern size change amount, and the image logarithmic slope of the photolithography pattern at the edge position is obtained.

[0014] Optionally, the calculating the exposure intensity of the photolithography pattern at the edge position, the change gradient of the exposure intensity, and the change amount of the pattern size includes:

[0015] The optical model is used to calculate the exposure intensity of the photolithography pattern at the edge position, the change gradient of the exposure intensity, and the change amount of the pattern size.

[0016] Optionally, the detecting the influence of the exposure intensity on the characteristic size of the lithography pattern based on the exposure intensity, the change gradient and the pattern size change to obtain the image logarithmic slope of the lithography pattern at the edge position includes:

[0017] Calculating the ratio of the change gradient to the change amount of the graphic size;

[0018] The absolute value of the ratio is obtained, and the ratio of the absolute value to the exposure intensity is calculated to obtain the image logarithmic slope of the lithography pattern at the edge position.

[0019] Optionally, the information for marking defects at the corresponding edge positions of the lithography pattern includes defect name, defect type, number of defects, defect position and the logarithmic slope of the image at the corresponding edge position.

[0020] Optionally, after determining that the OPC verification result of the lithography pattern is failed, the method further includes:

[0021] Correcting the photolithography pattern using the OPC model to obtain a corrected image;

[0022] The corrected image is used as the photolithography pattern, and the step of detecting the influence of exposure intensity on the characteristic size of the photolithography pattern is triggered to obtain the logarithmic slope of the image at the edge position of the photolithography pattern, until the logarithmic slope of the generated new image is not less than the preset slope threshold or is not within the preset slope range.

[0023] Optionally, the respectively determining whether the image logarithmic slope at each edge position is less than a preset slope threshold or is within a preset slope range includes:

[0024] Identifying the shape and size of the photolithographic pattern to obtain a target shape and a target size;

[0025] A preset slope threshold or a preset slope interval corresponding to the target shape and the target size is determined, and it is determined whether the image logarithmic slope at each edge position is less than the preset slope threshold or is within the preset slope interval.

[0026] In a second aspect, the present application discloses an OPC result verification device, comprising:

[0027] A pattern acquisition module, used to acquire the photolithography pattern after OPC correction;

[0028] A detection module, used for detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern, and obtaining the image logarithmic slope of the photolithography pattern at the edge position;

[0029] A determination module, used to determine whether the logarithmic slope of the image at each edge position is less than a preset slope threshold or is within a preset slope interval;

[0030] The OPC verification module is used to mark a defect at a corresponding edge position of the lithography pattern if the image logarithmic slope is less than the preset slope threshold or is within the preset slope interval, and determine that the OPC verification result of the lithography pattern is failed.

[0031] In a third aspect, the present application discloses an electronic device, comprising a processor and a memory; wherein the processor implements the aforementioned OPC result verification method when executing a computer program stored in the memory.

[0032] In a fourth aspect, the present application discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, the aforementioned OPC result verification method is implemented.

[0033] It can be seen that the present application first obtains the OPC-corrected lithography pattern, then detects the influence of the exposure intensity on the characteristic size of the lithography pattern, obtains the logarithmic slope of the image at the edge position of the lithography pattern, and then judges whether the logarithmic slope of the image at each edge position is less than the preset slope threshold or is in the preset slope range. If the logarithmic slope of the image is less than the preset slope threshold or is in the preset slope range, a defect mark is performed at the corresponding edge position of the lithography pattern, and the OPC verification result of the lithography pattern is determined to be failed. The present application detects the influence of exposure intensity on the characteristic size of the lithography pattern after OPC correction, obtains the image logarithmic slope of the lithography pattern at the edge position, and determines whether it is less than a preset slope threshold or is in a preset slope range. If so, a mark is made at the corresponding edge position, and the OPC verification result is determined to be failed. Since the image logarithmic slope (Image Log Slope, ILS) can be used to measure the local contrast of the imaging, it is particularly useful for semi-dense and isolated patterns. Therefore, by calculating the image logarithmic slope of the edge profile of the lithography pattern, the random effect of the photoresist can be solved, so that a larger ILS can be maintained when making OPC corrections. A larger ILS can help reduce LER (resist-edge log-slopes, photoresist edge logarithmic slope), especially the impact of photon shot noise. Therefore, by using the preset slope threshold and slope range, and comparing with the image logarithmic slope calculated in real time, the LER can be reduced by increasing the ILS, so that the exposure latitude (exposure latitude, EL) is increased, thereby improving the yield of the lithography chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0035] Figure 1 A flow chart of an OPC result verification method disclosed in this application;

[0036] Figure 2 A schematic diagram of a specific different shape feature disclosed in this application;

[0037] Figure 3 A schematic diagram of a specific graphic size feature disclosed in this application;

[0038] Figure 4 This is a schematic diagram of a specific ILS value distribution of different sizes disclosed in this application;

[0039] Figure 5 A schematic diagram of a specific ILS test result disclosed in this application;

[0040] Figure 6 A specific OPC result verification method flow chart disclosed in this application;

[0041] Figure 7 This is a schematic diagram of the structure of an OPC result verification device disclosed in this application;

[0042] Figure 8 This is a structural diagram of an electronic device disclosed in this application. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] The present application embodiment discloses an OPC result verification method, see Figure 1 As shown, the method includes:

[0045] Step S11: Obtaining the OPC-corrected photolithography pattern.

[0046] It should be noted that the OPC result verification solution proposed in this application can be applied to a pre-created OPC result verification system. When the OPC result needs to be verified, the system first obtains the OPC result to be verified, such as the lithography pattern corrected by the OPC model.

[0047] Step S12: detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern, and obtaining the image logarithmic slope of the photolithography pattern at the edge position.

[0048] In this embodiment, after obtaining the OPC-corrected lithography pattern, the lithography pattern is further subjected to ILS defect detection, that is, the degree to which the characteristic size of the lithography pattern is affected by the exposure intensity is detected, thereby obtaining the image logarithmic slope (i.e., ILS value) of the lithography pattern at the edge position.

[0049] Specifically, the detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern to obtain the image logarithmic slope of the photolithography pattern at the edge position may include: calculating the exposure intensity of the photolithography pattern at the edge position, the gradient of the exposure intensity change, and the amount of change in the pattern size; detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern based on the exposure intensity, the gradient of the exposure intensity change, and the amount of change in the pattern size to obtain the image logarithmic slope of the photolithography pattern at the edge position. That is, firstly respectively calculating the exposure intensity, the gradient of the exposure intensity change, and the amount of change in the pattern size at the edge position of the current photolithography pattern, and then detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern based on the calculated parameters, thereby obtaining the image logarithmic slope (i.e., ILS value) of the photolithography pattern at the edge position.

[0050] In a specific implementation, the calculation of the exposure intensity of the photolithography pattern at the edge position, the gradient of the exposure intensity change, and the amount of change in the pattern size may specifically include: using an optical model to calculate the exposure intensity of the photolithography pattern at the edge position, the gradient of the exposure intensity change, and the amount of change in the pattern size. In this embodiment, an optical model (such as an OPC model) may be used to calculate the exposure intensity I at the edge position of the current photolithography pattern, the gradient of the exposure intensity I change ΔI, and the amount of change in the pattern size Δx. In addition, it should be noted that the OPC model also includes exposure intensities at different positions.

[0051] In a specific implementation, the detection of the influence of the exposure intensity on the characteristic size of the lithographic pattern based on the exposure intensity, the change gradient and the pattern size change, and obtaining the image logarithmic slope of the lithographic pattern at the edge position may specifically include: calculating the ratio of the change gradient to the pattern size change; obtaining the absolute value of the ratio, and calculating the ratio of the absolute value to the exposure intensity, and obtaining the image logarithmic slope of the lithographic pattern at the edge position. In this embodiment, the calculation formula of the image logarithmic slope (i.e., ILS value) of the lithographic pattern at the edge position is:

[0052] ;

[0053] In the formula, I represents the exposure intensity at the edge of the photolithography pattern, ΔI represents the gradient of the exposure intensity I at the edge of the photolithography pattern, and Δx represents the change in the size of the photolithography pattern at the edge. In addition, it should be pointed out that the ILS value can reflect the effect of the change in light intensity on the size of the photolithography pattern. The larger the ILS value, the less the size of the photolithography pattern is affected by the light intensity, and the better the imaging quality; the smaller the ILS value, the greater the effect of the light intensity on the size of the photolithography pattern, and the worse the imaging quality.

[0054] Step S13: Determine whether the image logarithmic slope at each edge position is less than a preset slope threshold or is within a preset slope interval, respectively.

[0055] In this embodiment, after calculating the image logarithmic slope of the lithography pattern at each edge position, the image logarithmic slope (i.e., ILS value) at each edge position is compared with a preset slope threshold or whether it is within a preset slope interval, and it is determined respectively whether the image logarithmic slope (i.e., ILS value) at each edge position is less than the preset slope threshold or is within the preset slope interval.

[0056] It should be noted that whether it is a preset slope threshold or a preset slope interval, the thresholds involved are all greater than 0.

[0057] Specifically, the values of the preset slope threshold and the preset slope interval can be reasonably set according to the actual situation and requirements. In a specific implementation manner, various pre-designed feature patterns can be used to analyze the influence of lithography patterns with different features on the distribution of ILS values calculated, so as to obtain the distribution of ILS values under different circumstances. Among them, various features include the shape features and size features of the pattern; the shape features can specifically include patterns of various common shapes, such as Figure 2 the square pattern, rectangular pattern, "hui" character shape, "gong" character shape, "H" character shape, "T" character shape, etc. in; the size features can specifically include 3 parameters of L (length, the length of the pattern), W (width, the width of the pattern), and S (space, the spacing between patterns), as shown in Figure 3 shown, this set of feature patterns includes 3 rectangular patterns, and the length of each rectangle is L, the width is W, and the spacing between adjacent rectangles is S.

[0058] It can be understood that by changing Figure 3 the 3 parameters in, different numbers of pattern groups can be obtained. For example, by changing each of the 3 parameters once by the single variable method (such as changing L to L1, changing W to W1, and changing S to S1), the combined patterns can be groups; if all 3 parameters are changed twice (such as L to L1 or L2, W to W1 or W2, S to S1 or S2), the combined patterns can be groups; and so on. If all 3 parameters are changed n times, the combined patterns can be groups.

[0059] After creating the above-mentioned graphic groups of different categories, you can use the ORC verification software to test the influence of the width and spacing of rectangles on the distribution of ILS values. For example, first draw rectangles with widths of 50nm, 60nm, and 90nm, and spacings of 50nm, 60nm, and 110nm, and then test the distribution of ILS values ​​of graphics of different sizes. Figure 4 As shown in the black marked block in the middle, for dense graphics with a width of 50nm and a spacing of 50nm, the distribution of ILS values ​​is as follows: ILS defects with a value of 0≤ILS≤0.5 are distributed on the outside of the dense graphics group, and ILS defects with a value of 0.5<ILS≤1 are distributed on the inside of the dense graphics group, and the number of numerical defects in the latter is much larger than that in the former; while for dense graphics with a width of 60nm and a spacing of 60nm, the distribution of ILS values ​​is as follows: ILS defects with a value of 0≤ILS≤0.5 are distributed on the outside of the dense graphics group, and ILS defects with a value of 0.5<ILS≤1 are distributed on the inside of the dense graphics group, and the number of numerical defects in the latter is similar to that in the former; for dense graphics with a width of 90nm and a spacing of 110nm, the distribution of ILS is as follows: ILS defects with a value of 0≤ILS≤0.5 are distributed on the "cap" position of the dense graphics group, ILS defects with a value of 0.5<ILS≤1 are distributed on the "head" position at both ends of the dense graphics group, and ILS defects with a value of 1<ILS≤1.5 cover the remaining positions. It can be seen from the above three groups of test verification cases that the width of the pattern has a greater impact on the ILS value. If the same ILS defect threshold is set for patterns with smaller width and larger width, many defects will be detected for patterns with smaller size, but for patterns with larger size, the number of defects detected is very small. Therefore, in the actual OPC result verification, it is necessary to set a reasonable ILS defect threshold based on the pattern characteristics and combined with the lighting conditions of the exposure production to achieve a more ideal detection result.

[0060] Specifically, the step of respectively judging whether the image logarithmic slope at each edge position is less than a preset slope threshold or is within a preset slope interval may include: identifying the shape and size of the lithographic pattern to obtain a target shape and a target size; determining a preset slope threshold or a preset slope interval corresponding to the target shape and the target size, and respectively judging whether the image logarithmic slope at each edge position is less than the preset slope threshold or is within the preset slope interval. It should be noted that the present application sets different slope thresholds or slope intervals for lithographic patterns of different shapes and sizes in advance, so as to judge whether there is a defect at the edge position of the image. Specifically, the shape and size of the current lithographic pattern are firstly identified, and then the preset slope threshold or preset slope interval corresponding to the shape and size is determined, and then the image logarithmic slope (i.e., ILS value) at each edge position is respectively judged to be less than the corresponding preset slope threshold or is within the corresponding preset slope interval.

[0061] Step S14: If the image logarithmic slope is less than the preset slope threshold or is within the preset slope range, a defect mark is performed at a corresponding edge position of the lithography pattern, and the OPC verification result of the lithography pattern is determined to be failed.

[0062] In this embodiment, if the logarithmic slope of the above-mentioned image (i.e., the ILS value) is less than the preset slope threshold or is within the preset slope range, a defect mark is performed at the corresponding edge position of the lithography pattern, and the OPC verification result of the lithography pattern is determined to be failed, indicating that there is a defect at the edge position of the current lithography pattern and further OPC correction is required.

[0063] Correspondingly, if the above-mentioned image logarithmic slope (i.e., ILS value) is not less than the preset slope threshold or is not within the preset slope range, the OPC verification result of the lithography pattern is determined to be passed, indicating that there is no defect at the edge position of the current lithography pattern or the defect is small and no OPC correction is required.

[0064] It should be noted that the information for marking defects at the corresponding edge positions of the lithographic pattern may specifically include defect name, defect type, defect number, defect position and the image logarithmic slope (i.e., ILS value) at the corresponding edge position. By recording the defect marking information, subsequent browsing and viewing is facilitated. When a viewing request for the above defect marking information is received, it can be output in the format of a layout and a database.

[0065] It can be seen that the embodiment of the present application first obtains the OPC-corrected lithography pattern, then detects the influence of the exposure intensity on the characteristic size of the lithography pattern, obtains the logarithmic slope of the image at the edge position of the lithography pattern, and then judges whether the logarithmic slope of the image at each edge position is less than the preset slope threshold or is located in the preset slope range. If the logarithmic slope of the image is less than the preset slope threshold or is located in the preset slope range, a defect mark is performed at the corresponding edge position of the lithography pattern, and the OPC verification result of the lithography pattern is determined to be failed. The embodiment of the present application detects the influence of exposure intensity on the characteristic size of the lithography pattern after OPC correction, obtains the image logarithmic slope of the lithography pattern at the edge position, and determines whether it is less than a preset slope threshold or is located in a preset slope range. If so, a mark is made at the corresponding edge position, and the OPC verification result is determined to be failed. Since the image logarithmic slope can be used to measure the local contrast of the imaging, it is particularly useful for semi-dense and isolated patterns. Therefore, by calculating the image logarithmic slope of the edge profile of the lithography pattern, the random effect of the photoresist can be solved, so that a larger ILS can be maintained when making OPC corrections. A larger ILS can help reduce LER, especially the impact of photon shot noise. Therefore, by using the preset slope threshold and slope range, and comparing with the image logarithmic slope calculated in real time, the LER can be reduced by increasing the ILS, thereby increasing the exposure tolerance and improving the yield of the lithography chip.

[0066] For example, the distribution of ILS values ​​is analyzed for the width and spacing when the preset slope interval is set to 0.5 and the preset shape is a rectangle. Figure 5 As shown, first obtain the outline of the photolithography pattern after OPC correction (i.e. Figure 5 Then, the influence of exposure intensity on the characteristic size of the lithography pattern is detected, and the image logarithmic slope (i.e., ILS value) of the lithography pattern at the edge position is obtained and compared with the preset slope interval (0, 0.5]. If it is within the preset slope interval, a defect mark is performed (e.g. Figure 5 ), that is, when the edge contour position of the lithography pattern satisfies 0<ILS≤0.5, the pattern position will be marked as an ILS defect, indicating that there is an ILS risk, and the layout will be output. Further, the OPC correction can be made to the position of the ILS defect. It should be pointed out that Figure 5 The white blocks in the figure are the initial photolithography patterns without OPC correction.

[0067] The present application embodiment discloses a specific OPC result verification method, see Figure 6 As shown, the method includes:

[0068] Step S21: Obtaining the OPC-corrected lithography pattern.

[0069] Step S22: detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern, and obtaining the image logarithmic slope of the photolithography pattern at the edge position.

[0070] Step S23: determining whether the image logarithmic slope at each edge position is less than a preset slope threshold or is within a preset slope range.

[0071] Step S24: If the image logarithmic slope is less than the preset slope threshold or is within the preset slope range, a defect mark is performed at a corresponding edge position of the lithography pattern, and the OPC verification result of the lithography pattern is determined to be failed.

[0072] Step S25: using the OPC model to correct the photolithography pattern to obtain a corrected image.

[0073] In this embodiment, when the OPC verification result of the photolithography pattern is determined to be failed, the OPC model can be used to further correct the current photolithography pattern to obtain a corrected image.

[0074] Step S26: Use the corrected image as the photolithography pattern, and trigger the step of detecting the effect of exposure intensity on the characteristic size of the photolithography pattern to obtain the logarithmic slope of the image at the edge position of the photolithography pattern, until the generated new image logarithmic slope is not less than the preset slope threshold or is not within the preset slope range.

[0075] Next, the corrected image is used as a new photolithography pattern, and the step of detecting the effect of exposure intensity on the characteristic size of the photolithography pattern is triggered to obtain the logarithmic slope of the image at the edge position of the photolithography pattern, that is, the OPC verification of the corrected image is continued until the generated new image logarithmic slope (i.e., ILS value) is not less than the preset slope threshold or is not within the preset slope range.

[0076] For more specific processing procedures of the above steps S21 to S24, reference may be made to the corresponding contents disclosed in the above embodiments, which will not be described in detail here.

[0077] It can be seen that after the embodiment of the present application uses the preset slope threshold or the preset slope interval to determine that the OPC verification result of the current lithography pattern is failed, the OPC model is used to further correct the lithography pattern to obtain a corrected image, and the corrected image is used as a new lithography pattern to continue OPC verification until the logarithmic slope of the generated new image meets the preset conditions. By continuously verifying and correcting the lithography pattern, the lithography imaging can meet the preset accuracy requirements, thereby further improving the yield of the lithography chip.

[0078] Accordingly, the present application also discloses an OPC result verification device, see Figure 7 As shown, the device comprises:

[0079] A pattern acquisition module 11 is used to acquire the photolithography pattern after OPC correction;

[0080] A detection module 12, used for detecting the influence of the exposure intensity on the characteristic size of the lithography pattern, and obtaining the image logarithmic slope of the lithography pattern at the edge position;

[0081] A judging module 13, used to judge whether the logarithmic slope of the image at each edge position is less than a preset slope threshold or is within a preset slope interval;

[0082] The OPC verification module 14 is used to mark a defect at a corresponding edge position of the lithography pattern if the image logarithmic slope is less than the preset slope threshold or is within the preset slope range, and determine that the OPC verification result of the lithography pattern is failed.

[0083] Among them, the specific working processes of the above-mentioned modules can refer to the corresponding contents disclosed in the aforementioned embodiments, which will not be repeated here.

[0084] It can be seen that in the embodiment of the present application, the OPC-corrected lithography pattern is first obtained, and then the influence of the exposure intensity on the characteristic size of the lithography pattern is detected to obtain the logarithmic slope of the image at the edge position of the lithography pattern, and then it is determined whether the logarithmic slope of the image at each edge position is less than the preset slope threshold or is located in the preset slope range. If the logarithmic slope of the image is less than the preset slope threshold or is located in the preset slope range, a defect mark is performed at the corresponding edge position of the lithography pattern, and the OPC verification result of the lithography pattern is determined to be failed. The embodiment of the present application detects the influence of exposure intensity on the characteristic size of the lithography pattern after OPC correction, obtains the image logarithmic slope of the lithography pattern at the edge position, and determines whether it is less than a preset slope threshold or is located in a preset slope range. If so, a mark is made at the corresponding edge position, and the OPC verification result is determined to be failed. Since the image logarithmic slope can be used to measure the local contrast of the imaging, it is particularly useful for semi-dense and isolated patterns. Therefore, by calculating the image logarithmic slope of the edge profile of the lithography pattern, the random effect of the photoresist can be solved, so that a larger ILS can be maintained when making OPC corrections. A larger ILS can help reduce LER, especially the impact of photon shot noise. Therefore, by using the preset slope threshold and slope range, and comparing with the image logarithmic slope calculated in real time, the LER can be reduced by increasing the ILS, thereby increasing the exposure tolerance and improving the yield of the lithography chip.

[0085] In some specific embodiments, the detection module 12 may specifically include:

[0086] A first calculation unit, used for calculating the exposure intensity of the photolithography pattern at the edge position, the change gradient of the exposure intensity, and the change amount of the pattern size;

[0087] The first detection unit is used to detect the influence of the exposure intensity on the characteristic size of the lithography pattern based on the exposure intensity, the change gradient and the pattern size change, and obtain the image logarithmic slope of the lithography pattern at the edge position.

[0088] In some specific embodiments, the first calculation unit may specifically include:

[0089] The second calculation unit is used to calculate the exposure intensity of the photolithography pattern at the edge position, the change gradient of the exposure intensity, and the change amount of the pattern size by using an optical model.

[0090] In some specific embodiments, the first detection unit may specifically include:

[0091] A third calculation unit, used for calculating the ratio of the change gradient to the change amount of the graphic size;

[0092] an absolute value obtaining unit, used to obtain the absolute value of the ratio;

[0093] The fourth calculation and acquisition unit is used to calculate the ratio of the absolute value to the exposure intensity to obtain the image logarithmic slope of the lithography pattern at the edge position.

[0094] In some specific embodiments, the information for marking defects at the corresponding edge positions of the lithographic patterns includes defect name, defect type, defect number, defect position, and the logarithmic slope of the image at the corresponding edge positions.

[0095] In some specific embodiments, the OPC verification module 14 may further include:

[0096] A pattern correction unit, used for correcting the photolithography pattern using an OPC model to obtain a corrected image;

[0097] The second detection unit is used to use the corrected image as the photolithography pattern and trigger the step of detecting the influence of exposure intensity on the characteristic size of the photolithography pattern to obtain the logarithmic slope of the image at the edge position of the photolithography pattern, until the generated new image logarithmic slope is not less than the preset slope threshold or is not within the preset slope range.

[0098] In some specific embodiments, the determination module 13 may specifically include:

[0099] An identification unit, used for identifying the shape and size of the photolithography pattern to obtain a target shape and a target size;

[0100] a determining unit, configured to determine a preset slope threshold or a preset slope interval corresponding to the target shape and the target size;

[0101] The judging unit is used to judge whether the image logarithmic slope at each edge position is less than the preset slope threshold or is within the preset slope interval.

[0102] Furthermore, the present application also discloses an electronic device. Figure 8 This is a structural diagram of an electronic device 20 according to an exemplary embodiment. The content in the diagram cannot be regarded as any limitation on the scope of use of the present application.

[0103] Figure 8 A schematic diagram of the structure of an electronic device 20 provided in an embodiment of the present application. The electronic device 20 may specifically include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25, and a communication bus 26. The memory 22 is used to store a computer program, which is loaded and executed by the processor 21 to implement the relevant steps in the OPC result verification method disclosed in any of the aforementioned embodiments. In addition, the electronic device 20 in this embodiment may specifically be an electronic computer.

[0104] In this embodiment, the power supply 23 is used to provide working voltage for each hardware device on the electronic device 20; the communication interface 24 can create a data transmission channel between the electronic device 20 and the external device, and the communication protocol it follows is any communication protocol that can be applied to the technical solution of the present application, and is not specifically limited here; the input and output interface 25 is used to obtain external input data or output data to the outside world, and its specific interface type can be selected according to specific application needs and is not specifically limited here.

[0105] In addition, the memory 22, as a carrier for storing resources, can be a read-only memory, a random access memory, a disk or an optical disk, etc. The resources stored thereon can include an operating system 221, a computer program 222, etc., and the storage method can be temporary storage or permanent storage.

[0106] The operating system 221 is used to manage and control the hardware devices and computer program 222 on the electronic device 20, which can be Windows Server, Netware, Unix, Linux, etc. In addition to including a computer program that can be used to complete the OPC result verification method performed by the electronic device 20 disclosed in any of the aforementioned embodiments, the computer program 222 can further include a computer program that can be used to complete other specific tasks.

[0107] Furthermore, the present application also discloses a computer-readable storage medium for storing a computer program; wherein the computer program, when executed by a processor, implements the aforementioned disclosed OPC result verification method. The specific steps of the method can refer to the corresponding contents disclosed in the aforementioned embodiments, and will not be repeated here.

[0108] Furthermore, an embodiment of the present application also discloses a computer program product, including a computer program / instruction, which implements the steps of the OPC result verification method disclosed above when executed by a processor.

[0109] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0110] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0111] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0112] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0113] The above is a detailed introduction to an OPC result verification method, device, equipment and storage medium provided by the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. An OPC result verification method, characterized in that: include: Obtaining the OPC-corrected lithography pattern; Detecting the influence of exposure intensity on the characteristic size of the lithographic pattern, and obtaining an image logarithmic slope (ILS) of the lithographic pattern at an edge position; Determine whether the image logarithmic slope at each edge position is less than a preset slope threshold or is within a preset slope range; If the image logarithmic slope is less than the preset slope threshold or is within the preset slope interval, a defect mark is performed at a corresponding edge position of the lithography pattern, and an OPC verification result of the lithography pattern is determined to be failed; The detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern to obtain the logarithmic slope of the image of the photolithography pattern at the edge position includes: calculating the exposure intensity of the photolithography pattern at the edge position, the gradient of the exposure intensity change, and the amount of change in the pattern size; detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern to obtain the logarithmic slope of the image of the photolithography pattern at the edge position based on the exposure intensity, the gradient of the change, and the amount of change in the pattern size; The detecting the influence of the exposure intensity on the characteristic size of the photolithography pattern and the pattern size change based on the exposure intensity, the change gradient and the pattern size change to obtain the image logarithmic slope of the photolithography pattern at the edge position includes: calculating the ratio of the change gradient to the pattern size change; obtaining the absolute value of the ratio, and calculating the ratio of the absolute value to the exposure intensity to obtain the image logarithmic slope of the photolithography pattern at the edge position; The OPC result verification method also includes: using pre-designed graphics of various features to analyze the impact of different features of lithography graphics on the distribution of calculated ILS values, obtaining the distribution of ILS values ​​under different circumstances, and determining the preset slope threshold or the preset slope range based on the distribution of ILS values ​​under different circumstances; wherein the various features include shape features and size features of the graphics.

2. The OPC result verification method according to claim 1, characterized in that: The calculating of the exposure intensity of the photolithography pattern at the edge position, the change gradient of the exposure intensity, and the change amount of the pattern size includes: The optical model is used to calculate the exposure intensity of the photolithography pattern at the edge position, the change gradient of the exposure intensity, and the change amount of the pattern size.

3. The OPC result verification method according to claim 1, characterized in that: The information for marking defects at the corresponding edge positions of the photolithography patterns includes defect name, defect type, defect number, defect position and the logarithmic slope of the image at the corresponding edge positions.

4. The OPC result verification method according to claim 1, characterized in that: After determining that the OPC verification result of the photolithography pattern is failed, the method further includes: Correcting the photolithography pattern using the OPC model to obtain a corrected image; The corrected image is used as the photolithography pattern, and the step of detecting the influence of exposure intensity on the characteristic size of the photolithography pattern is triggered to obtain the logarithmic slope of the image at the edge position of the photolithography pattern, until the logarithmic slope of the generated new image is not less than the preset slope threshold or is not within the preset slope range.

5. The OPC result verification method according to any one of claims 1 to 4, characterized in that: The step of respectively determining whether the image logarithmic slope at each edge position is less than a preset slope threshold or is within a preset slope range includes: Identifying the shape and size of the photolithographic pattern to obtain a target shape and a target size; A preset slope threshold or a preset slope interval corresponding to the target shape and the target size is determined, and it is determined whether the image logarithmic slope at each edge position is less than the preset slope threshold or is within the preset slope interval.

6. An OPC result verification device, characterized in that: include: A pattern acquisition module, used to acquire the photolithography pattern after OPC correction; A detection module, used for detecting the influence of the exposure intensity on the characteristic size of the lithography pattern, and obtaining the image logarithmic slope (ILS) of the lithography pattern at the edge position; A determination module, used to determine whether the logarithmic slope of the image at each edge position is less than a preset slope threshold or is within a preset slope interval; An OPC verification module, configured to mark a defect at a corresponding edge position of the lithography pattern if the image logarithmic slope is less than the preset slope threshold or is within the preset slope interval, and determine that the OPC verification result of the lithography pattern is failed; The detection module is specifically used to calculate the exposure intensity of the photolithography pattern at the edge position, the change gradient of the exposure intensity, and the change amount of the pattern size; based on the exposure intensity, the change gradient and the change amount of the pattern size, detect the influence of the exposure intensity on the characteristic size of the photolithography pattern, and obtain the image logarithmic slope of the photolithography pattern at the edge position; The detection module is specifically used to calculate the ratio of the change gradient to the change amount of the pattern size; obtain the absolute value of the ratio, and calculate the ratio of the absolute value to the exposure intensity to obtain the image logarithmic slope of the lithography pattern at the edge position; The device is also used to analyze the influence of different characteristics of lithography patterns on the distribution of calculated ILS values ​​using pre-designed graphics of various characteristics, obtain the distribution of ILS values ​​under different circumstances, and determine the preset slope threshold or the preset slope range based on the distribution of ILS values ​​under different circumstances; wherein the various characteristics include shape characteristics and size characteristics of the graphics.

7. An electronic device, characterized in that: The method comprises a processor and a memory; wherein, when the processor executes the computer program stored in the memory, the OPC result verification method according to any one of claims 1 to 5 is implemented.

8. A computer-readable storage medium, characterized in that: Used to store a computer program; wherein, when the computer program is executed by a processor, the OPC result verification method according to any one of claims 1 to 5 is implemented.

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