Evaluation method and equipment of photoresist simulation model, medium and product

Abstract

The invention discloses an evaluation method and equipment of a photoresist simulation model, a medium and a product, and relates to the technical field of photoetching simulation. The evaluation method of the photoresist simulation model comprises the following steps: obtaining photoresist parameters and an optical modeling file of a to-be-evaluated photoresist simulation model, wherein the optical modeling file comprises original optical modeling parameters for constructing the to-be-evaluated photoresist simulation model; constructing a rotary photoresist simulation model according to the photoresist parameters and the optical modeling file; inputting the rotary optical modeling parameters into the rotary photoresist simulation model to obtain a rotary graph size; comparing the rotation pattern size with a reference pattern size to obtain a size difference value, the reference pattern size being a pattern size obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated; and according to the size difference value, evaluating whether the to-be-evaluated photoresist simulation model has an overfitting phenomenon or not.

Description

Technical Field

[0001] The present application belongs to the field of photolithography simulation technology, and in particular, relates to an evaluation method, device, medium and product of a photoresist simulation model. Background Art

[0002] In integrated circuit manufacturing, the structure of high-performance chips is becoming more and more complex, and the line width is also constantly decreasing. As the line width decreases, the optical proximity effect will cause the imaging gap of the mask pattern on the photoresist to gradually increase. Therefore, it is very important to correct the influence of the optical proximity effect.

[0003] In the existing method, the photoresist simulation model is used to correct the influence of the optical proximity effect in the photolithography process. However, when creating the photoresist simulation model, the selected optical modeling parameters often have a situation where the proportion of test layouts in certain directions is too large, which can easily lead to the overfitting phenomenon of the photoresist simulation model for the test layouts in these directions with too large a proportion.

[0004] However, existing methods cannot accurately identify whether the created photoresist simulation model has overfitting phenomenon, and the accuracy of the evaluation of the photoresist simulation model is not high. Summary of the invention

[0005] The embodiments of the present application provide a method, device, medium and product for evaluating a photoresist simulation model, which can improve the accuracy of evaluating the photoresist simulation model.

[0006] In one aspect of an embodiment of the present application, a method for evaluating a photoresist simulation model is provided, comprising:

[0007] Obtaining photoresist parameters and an optical modeling file of a photoresist simulation model to be evaluated, wherein the optical modeling file includes original optical modeling parameters used to construct the photoresist simulation model to be evaluated;

[0008] According to the photoresist parameters and the optical modeling file, a rotational photoresist simulation model is constructed, wherein the rotational photoresist simulation model is a model for performing photoresist imaging simulation on the rotational optical modeling parameters after the original optical modeling parameters are rotated by a target angle;

[0009] Inputting the rotation optical modeling parameters into the rotation photoresist simulation model to obtain the rotation pattern size;

[0010] Compare the size of the rotated pattern with the size of the reference pattern to obtain a size difference, where the reference pattern size is the pattern size obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated;

[0011] Based on the size difference, it is evaluated whether the photoresist simulation model to be evaluated has overfitting phenomenon.

[0012] In one aspect of an embodiment of the present application, a device for evaluating a photoresist simulation model is provided, comprising:

[0013] A parameter acquisition module, used to acquire photoresist parameters and an optical modeling file of a photoresist simulation model to be evaluated, wherein the optical modeling file includes original optical modeling parameters used to construct the photoresist simulation model to be evaluated;

[0014] A model building module is used to build a rotational photoresist simulation model according to the photoresist parameters and the optical modeling file, wherein the rotational photoresist simulation model is a model for performing photoresist imaging simulation on the rotational optical modeling parameters after the original optical modeling parameters are rotated by a target angle;

[0015] A size determination module is used to input the rotation optical modeling parameters into the rotation photoresist simulation model to obtain the rotation graphic size;

[0016] A difference determination module is used to compare the size of the rotated pattern with the size of the reference pattern to obtain a size difference, where the reference pattern size is the pattern size obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated;

[0017] The model evaluation module is used to evaluate whether the photoresist simulation model to be evaluated has overfitting phenomenon according to the size difference.

[0018] According to one aspect of an embodiment of the present application, an electronic device is provided, which includes: a memory and a program or instruction stored in the memory and executable on a processor, wherein when the program or instruction is executed by the processor, an evaluation method for a photoresist simulation model as provided in any aspect of the above-mentioned embodiment of the present application is implemented.

[0019] In one aspect of an embodiment of the present application, a readable storage medium is provided, on which a program or instruction is stored. When the program or instruction is executed by a processor, a method for evaluating a photoresist simulation model provided in any aspect of the above-mentioned embodiment of the present application is implemented.

[0020] According to one aspect of an embodiment of the present application, a computer program product is provided. When instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes a method for evaluating a photoresist simulation model as provided in any aspect of the above-mentioned embodiment of the present application.

[0021] In the evaluation method of the photoresist simulation model provided by the embodiment of the present application, according to the photoresist parameters and the optical modeling file of the photoresist simulation model to be evaluated, a rotating photoresist simulation model is constructed, which is used to perform photoresist imaging simulation on the rotating optical modeling parameters after the original optical modeling parameters are rotated by the target angle. In this way, by rotating the photoresist simulation model, it can be accurately determined whether there is a deviation between the graphic sizes obtained by performing photoresist imaging simulation on the optical modeling parameters after the rotation target angle and the optical modeling parameters before the rotation, thereby verifying whether the photoresist simulation model to be evaluated meets the rotational symmetry. By verifying whether the target photoresist simulation model meets the rotational symmetry, it is accurately determined whether the photoresist simulation model to be evaluated will have an overfitting phenomenon. In this way, the embodiment of the present application can accurately identify whether the photoresist simulation model to be evaluated has an overfitting phenomenon by rotating the photoresist simulation model, thereby improving the accuracy of the evaluation of the photoresist simulation model. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 It is a flowchart of a method for evaluating a photoresist simulation model provided by an embodiment of the present application;

[0024] Figure 2 It is a schematic diagram of rotating optical modeling parameters obtained by rotating the first original optical modeling parameters provided by an embodiment of the present application;

[0025] Figure 3 It is a schematic diagram of rotating optical modeling parameters obtained by rotating the second original optical modeling parameters provided by an embodiment of the present application;

[0026] Figure 4 It is a schematic diagram comparing the original photoresist simulation profile and the rotated photoresist simulation profile provided by an embodiment of the present application;

[0027] Figure 5 It is a structural schematic diagram of an evaluation device for a photoresist simulation model provided by an embodiment of the present application;

[0028] Figure 6 It is a structural schematic diagram of an evaluation device for a photoresist simulation model provided in one embodiment of the present application. DETAILED DESCRIPTION

[0029] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0030] 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 statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0031] It should be noted that the acquisition, storage, use, and processing of data in the technical solution of this application are in compliance with the relevant provisions of national laws and regulations.

[0032] It should be noted that in the embodiments of the present application, certain software, components, models and other existing solutions in the industry may be mentioned, and they should be regarded as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution of the present application, but it does not mean that the applicant has or will necessarily use the solution.

[0033] In the existing methods, the photoresist simulation model is used to correct the influence of the optical proximity effect in the photolithography process. In the creation of the photoresist simulation model, the selected optical modeling parameters often have a situation where the proportion of the test layout in certain directions is too large, which can easily lead to the overfitting phenomenon of the photoresist simulation model for the test layout in these directions with too large a proportion. However, the existing methods cannot accurately identify whether the created photoresist simulation model has an overfitting phenomenon, and the accuracy of the evaluation of the photoresist simulation model is not high.

[0034] The purpose of the present application is to provide an evaluation method, device, medium and product of a photoresist simulation model. In the evaluation method of the photoresist simulation model provided in the embodiment of the present application, according to the photoresist parameters and optical modeling file of the photoresist simulation model to be evaluated, a rotating photoresist simulation model is constructed, which is used to perform photoresist imaging simulation on the rotating optical modeling parameters after the original optical modeling parameters are rotated by a target angle. In this way, by rotating the photoresist simulation model, it is possible to accurately determine whether there is a deviation between the graphic sizes obtained by performing photoresist imaging simulation on the optical modeling parameters after the rotation target angle and the optical modeling parameters before the rotation, thereby verifying whether the photoresist simulation model to be evaluated conforms to rotational symmetry. By verifying whether the target photoresist simulation model conforms to rotational symmetry, it is accurately determined whether the photoresist simulation model to be evaluated will have an overfitting phenomenon. In this way, the embodiment of the present application can accurately identify whether the photoresist simulation model to be evaluated has an overfitting phenomenon by rotating the photoresist simulation model, thereby improving the accuracy of the evaluation of the photoresist simulation model.

[0035] The following describes specific embodiments of the evaluation method, device, medium and product of the photoresist simulation model provided by the embodiments of the present application. First, the evaluation method of the photoresist simulation model is introduced.

[0036] Figure 1 A schematic flow chart of a method for evaluating a photoresist simulation model is provided. The method for evaluating a photoresist simulation model can be applied to a server. The method for evaluating a photoresist simulation model can include the following steps S101 to S104.

[0037] S101, obtaining photoresist parameters and an optical modeling file of a photoresist simulation model to be evaluated, where the optical modeling file includes original optical modeling parameters used to construct the photoresist simulation model to be evaluated.

[0038] In this embodiment, the photoresist parameters are used to characterize the parameters and coefficients of the photoresist part in the original photoresist simulation model to be evaluated. For example, the photoresist parameters may include basic physical parameters of the photoresist and basic chemical parameters of the photoresist. The basic physical parameters of the photoresist may include thickness, refractive index, and absorption coefficient, etc., and the basic chemical parameters of the photoresist may include sensitivity, contrast, and etching resistance, etc.

[0039] The optical modeling file includes original optical modeling parameters used to construct the photoresist simulation model to be evaluated. For example, the original optical modeling parameters may include light source characteristics and mask patterns.

[0040] As an example, the server first determines the photoresist simulation model to be evaluated, and then obtains the optical modeling file required to build the photoresist simulation model to be evaluated, and simultaneously obtains the parameters and coefficients corresponding to the photoresist part in the photoresist simulation model to be evaluated.

[0041] S102, constructing a rotational photoresist simulation model according to the photoresist parameters and the optical modeling file, wherein the rotational photoresist simulation model is a model for performing photoresist imaging simulation on the rotational optical modeling parameters after the original optical modeling parameters are rotated by a target angle.

[0042] In this embodiment, the rotation optical modeling parameters are used to characterize new parameters obtained by rotating the original optical modeling parameters by a target angle, wherein the target angle is a preset value, and for example, the target angle may be 90 degrees.

[0043] The rotating photoresist simulation model is a model used to simulate photoresist imaging using rotating optical modeling parameters.

[0044] As an example, after obtaining the photoresist parameters and the optical modeling file, the server rotates each original optical modeling parameter in the optical modeling file by a target angle to obtain the corresponding rotated optical modeling parameters. Then, based on the rotated optical modeling parameters and the photoresist parameters, the photoresist simulation model to be evaluated is corrected to construct a rotated photoresist simulation model.

[0045] S103, inputting the rotation optical modeling parameters into the rotation photoresist simulation model to obtain the rotation pattern size.

[0046] In this embodiment, the rotational graphic size is used to characterize the size of the graphic outline generated by the rotational optical modeling parameter simulation.

[0047] As an example, the server inputs the rotation optical modeling parameters into the rotation photoresist simulation model for simulation calculation to obtain the rotation graphic size corresponding to the rotation optical modeling parameters. The rotation graphic size reflects the imaging effect of the photoresist under the rotation condition.

[0048] S104, comparing the size of the rotated pattern with the size of the reference pattern to obtain a size difference, where the reference pattern size is the pattern size obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated.

[0049] In this embodiment, the reference pattern size refers to the size of the pattern outline obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated, which represents the photoresist imaging effect under the condition of no rotation (ie, standard condition).

[0050] The size difference is used to characterize the difference between the size of the rotated pattern and the size of the reference pattern, wherein the size difference reflects the change of the pattern profile generated by the optical simulation of the photoresist simulation model to be evaluated under the rotation condition.

[0051] As an example, the server inputs the original optical modeling parameters into the photoresist simulation model to be evaluated for simulation calculation, and obtains the reference pattern size corresponding to the original optical modeling parameters. The rotated pattern size is then compared with the reference pattern size to calculate the size difference between them.

[0052] S105, evaluating whether the photoresist simulation model to be evaluated has an overfitting phenomenon according to the size difference.

[0053] In this embodiment, overfitting means that the photoresist simulation model to be evaluated is too dependent on the original optical modeling parameters in a specific direction, and cannot be well generalized to the rotated optical modeling parameters in different directions.

[0054] Specifically, when the photoresist simulation model to be evaluated performs well on the original optical modeling parameters, but the rotated photoresist simulation model associated with the photoresist simulation model to be evaluated performs poorly on the rotated optical modeling parameters, it is considered that the photoresist simulation model to be evaluated is overfitted.

[0055] As an example, when the size difference is greater than or equal to a preset difference threshold, that is, when the size of the rotated pattern is significantly different from the size of the reference pattern, it is determined that the photoresist simulation model to be evaluated has an overfitting phenomenon.

[0056] When the size difference is less than a preset difference threshold, that is, when the size of the rotated pattern is smaller than the size of the reference pattern, it is determined that the photoresist simulation model to be evaluated does not have an overfitting phenomenon.

[0057] In the evaluation method of the photoresist simulation model provided by the present embodiment, according to the photoresist parameters and the optical modeling file of the photoresist simulation model to be evaluated, a rotating photoresist simulation model is constructed, which is used to perform photoresist imaging simulation on the rotating optical modeling parameters after the original optical modeling parameters are rotated by the target angle. In this way, by rotating the photoresist simulation model, it can be accurately determined whether there is a deviation between the graphic sizes obtained by respectively performing photoresist imaging simulation on the optical modeling parameters after the rotation target angle and the optical modeling parameters before the rotation, thereby verifying whether the photoresist simulation model to be evaluated conforms to the rotational symmetry. By verifying whether the target photoresist simulation model conforms to the rotational symmetry, it is accurately determined whether the photoresist simulation model to be evaluated will have an overfitting phenomenon. In this way, the embodiment of the present application can accurately identify whether the photoresist simulation model to be evaluated has an overfitting phenomenon by rotating the photoresist simulation model, thereby improving the accuracy of the evaluation of the photoresist simulation model.

[0058] As an optional embodiment, S102 may specifically include:

[0059] Rotating the original optical modeling parameters in the optical modeling file by at least one target angle to obtain the rotated optical modeling parameters after being rotated by the target angle;

[0060] Perform optical simulation on the rotational optical modeling parameters and construct a rotational optical simulation model;

[0061] A rotating photoresist simulation model is constructed according to the photoresist parameters of the photoresist simulation model to be evaluated and the rotating optical simulation model.

[0062] In this embodiment, the target angle may be one or more. In the case of multiple target angles, multiple target angles may be randomly selected within a preset angle range, or multiple target angles may be regularly selected according to a preset selection strategy. For example, a target angle may be selected every 45 degrees clockwise from 0 degrees until 360 degrees is reached, thereby obtaining multiple target angles.

[0063] When there are multiple target angles, each target angle corresponds to a rotating optical simulation model and a rotating photoresist simulation model.

[0064] As an example, the server first extracts all original optical modeling parameters from the optical modeling file, and rotates each original optical modeling parameter according to the selected target angle through a rotation matrix, thereby obtaining the rotated optical modeling parameters after rotating to the target angle.

[0065] Then, obtain target optical simulation software, such as Zemax, CODEV, etc. According to the rotational optical modeling parameters, use the target optical simulation software to set parameters and obtain a rotational optical simulation model.

[0066] Finally, photoresist parameters are extracted from the photoresist simulation model to be evaluated, and the extracted photoresist parameters are combined with the rotational optical simulation model to construct a rotational photoresist simulation model. Specifically, the photoresist parameters are input into the rotational optical simulation model to simulate the behavior of the photoresist during the lithography process.

[0067] As another example, the original optical modeling parameters include the original test layout and the original measurement data, and the rotated optical modeling parameters include the rotated test layout and the rotated measurement data. Figure 2 As shown, a schematic diagram of rotating the original optical modeling parameters to obtain the rotated optical modeling parameters is provided. Among them, 2-a is the original test layout and the original measurement data. After rotating it 90 degrees clockwise, the rotated test layout and the rotated measurement data of 2-b can be obtained.

[0068] As another example, the original optical modeling parameters include the original test light source, and the rotated optical modeling parameters include the rotated test light source. Figure 3 As shown, a schematic diagram of rotating the original optical modeling parameters to obtain the rotated optical modeling parameters is provided. Among them, 3-a is the original test light source, and after rotating it 90 degrees clockwise, the rotated test light source of 3-b can be obtained.

[0069] Through this embodiment, the original optical modeling parameters are rotated to obtain the rotated optical modeling parameters, and the rotated optical modeling parameters are optically simulated to obtain the rotated optical simulation model, so as to construct the rotated photoresist simulation model according to the rotated optical simulation model and the photoresist parameters of the photoresist simulation model to be evaluated. In this way, a rotated photoresist simulation model corresponding to the photoresist simulation model to be evaluated is constructed, which helps to accurately identify whether the photoresist simulation model to be evaluated has an overfitting phenomenon through the rotated photoresist simulation model, thereby improving the accuracy of the evaluation of the photoresist simulation model.

[0070] As an optional embodiment, the rotation optical modeling parameters include a rotation test layout, rotation measurement data, and a rotation test light source;

[0071] Perform optical simulation on the rotational optical modeling parameters and construct a rotational optical simulation model, which may specifically include:

[0072] Obtaining a rotation cross-sensing coefficient corresponding to a rotation test light source, where the rotation cross-sensing coefficient is used to measure the degree of mutual interference of optical signals corresponding to a rotation test pattern during transmission;

[0073] Optical simulation is performed on the rotation test layout, rotation measurement data and rotation cross-sensing coefficient to build a rotation optical simulation model.

[0074] In this embodiment, the transmission process of the optical signal is often interfered by various factors, such as attenuation, dispersion, reflection, scattering, etc. These interference factors will cause the quality of the optical signal to deteriorate, thereby affecting the accuracy of the test. In order to measure the degree of mutual interference of the optical signal during the transmission process, the rotational cross-sensing coefficient is introduced when constructing the rotational optical simulation model, so that the constructed rotational optical simulation model is more accurate.

[0075] As an example, an optical test platform is prepared in advance, which includes multiple test light sources, test layouts, optical signal receivers, and related measurement equipment. The test light source can be a laser light source or other stable light source, and the optical signal emitted by it should have a certain intensity and wavelength range.

[0076] Then, start various test light sources respectively, so that the light signals they emit pass through the test layout. Use an optical signal receiver to receive the light signal after passing through the test layout, and record its intensity, phase and other parameters. According to the light signal data corresponding to the various test light sources, calculate the cross-sensing coefficients of various test light sources respectively. Specifically, the cross-sensing coefficient can be obtained by comparing the intensity difference and phase change between different light signals. Then, a cross-sensing coefficient comparison table is generated for various test light sources and the corresponding cross-sensing coefficients.

[0077] When it is necessary to construct a rotational optical simulation model corresponding to the rotational optical modeling parameters, the rotational test light source is first compared with the cross-sensing coefficient comparison table to obtain the rotational cross-sensing coefficient corresponding to the rotational test light source.

[0078] Then, the target optical simulation software is used to establish an initial optical simulation model, and then the information of the rotation test layout and the rotation measurement data are imported into the initial optical simulation model. At the same time, the optical signal interference parameter is set according to the pre-obtained rotation cross-sensing coefficient.

[0079] Then, the optical simulation model is run to simulate the transmission process of the optical signal in the test layout to obtain the simulation results. Finally, the parameters of the optical simulation model are adjusted according to the simulation results to obtain the final rotation optical simulation model.

[0080] Through this embodiment, the rotation cross-sensing coefficient corresponding to the rotating test light source is obtained, and the rotation cross-sensing coefficient is used to perform optical simulation to construct a rotation optical simulation model. In this way, the rotation cross-sensing coefficient is used to accurately construct a rotation optical simulation model, which helps to further construct a rotation photoresist simulation model based on the rotation optical simulation model, accurately identify whether the photoresist simulation model to be evaluated has an overfitting phenomenon, and improve the accuracy of the evaluation of the photoresist simulation model.

[0081] As an optional embodiment, obtaining the rotation cross-sensing coefficient corresponding to the rotating test light source may specifically include:

[0082] Determine, according to the rotating test light source, a first light source parameter and a second light source parameter corresponding to the rotating test light source, wherein the first light source parameter is a light source parameter whose corresponding first parameter value will change when the original test light source is rotated, and the second light source parameter is a light source parameter whose corresponding second parameter value will not change when the original test light source is rotated;

[0083] According to the target angle corresponding to the rotating test light source, a first parameter value corresponding to the first light source parameter is updated to obtain a first updated parameter value;

[0084] The rotation cross-sensing coefficient corresponding to the rotating test light source is determined according to the first updated parameter value and the second parameter value.

[0085] In this embodiment, the test light source has many light source parameters, among which some light source parameters will change with the rotation of the test light source, and these parameters are first light source parameters, such as the coordinates of light source feature points related to generating cross-sensing coefficients and the polarization direction of the light source.

[0086] There are also some light source parameters whose parameter values ​​do not change as the test light source rotates. These parameters are the second light source parameters, such as the light source wavelength.

[0087] As an example, after the original test light source is rotated by a target angle to obtain a rotated test light source, a first light source parameter and a second light source parameter in the rotated test light source are acquired.

[0088] Then, for the first light source parameter, its corresponding parameter value is updated according to the target rotation angle to obtain a first updated parameter value; and for the second light source parameter, its corresponding parameter value remains the parameter value of the original test light source before rotation.

[0089] Finally, the original cross-sensing coefficient of the original test light source is updated using the first update parameter value and the second parameter value to obtain the rotational cross-sensing coefficient of the rotated test light source.

[0090] Through this embodiment, according to the rotation angle of the rotating test light source, the first light source parameter is updated to obtain the first updated parameter value, so as to determine the rotation cross-sensing coefficient of the rotating test light source according to the first updated parameter value. In this way, it is helpful to build a more accurate rotation optical simulation model according to the rotation cross-sensing coefficient, so as to accurately identify whether the photoresist simulation model to be evaluated has an overfitting phenomenon, and improve the accuracy of the evaluation of the photoresist simulation model.

[0091] As an optional embodiment, optical simulation is performed on the rotation test layout, the rotation measurement data, and the rotation cross-sensing coefficient to construct a rotation optical simulation model, which may specifically include:

[0092] Determine the rotation mask information according to the rotation test layout and the rotation measurement data;

[0093] The rotation mask information is convolved with the rotation cross sensing coefficient to obtain a rotational spatial image, which is used to characterize the light intensity distribution on the imaging surface corresponding to the rotational optical modeling parameters after the target angle is rotated;

[0094] According to the rotating spatial image, a rotating optical simulation model is constructed.

[0095] In this embodiment, the rotation mask information is used to represent the mask information determined according to the optical modeling parameters after the target angle is rotated. The rotation mask information may be a function or matrix describing the change of the optical parameters during the target angle rotation process.

[0096] As an example, the server determines the rotation mask information according to the rotation test layout and the rotation measurement data by experimental data fitting and numerical calculation. The specific form of the rotation mask information may vary depending on factors such as the design of the test layout and the characteristics of the rotation angle. For example, the rotation mask information may be represented in a matrix form.

[0097] Then, the rotation mask information is convolved with the rotation cross-sensing coefficient to obtain a rotational aerial image, which can intuitively show the impact of the rotation target angle on the imaging quality of the optical system. For example, as the rotation angle increases, the light intensity gradually decreases and image shift occurs.

[0098] Finally, according to the rotating spatial image, a rotational optical simulation model is constructed using optical simulation software or tools.

[0099] Through this embodiment, optical simulation is performed on the rotation test layout, rotation measurement data, and rotation cross-sensing coefficient to construct a rotation optical simulation model. This helps to further construct a rotation photoresist simulation model based on the rotation optical simulation model, thereby accurately identifying whether the photoresist simulation model to be evaluated has an overfitting phenomenon, thereby improving the accuracy of the evaluation of the photoresist simulation model.

[0100] As an optional embodiment, S103 may specifically include:

[0101] Inputting the rotation test layout and the rotation measurement data into the rotation photoresist simulation model to obtain the rotation photoresist simulation profile;

[0102] The size of the rotated pattern is determined according to the simulated profile of the rotated photoresist.

[0103] In this embodiment, the rotation test layout and the rotation measurement data are input into the rotation photoresist simulation model, and the rotation photoresist simulation model performs simulation calculations according to the input data and preset photoresist parameters.

[0104] After simulation calculation, the spin photoresist simulation model will output the simulation profile of the spin photoresist, which is the expected shape of the photoresist after exposure and development in the photolithography process.

[0105] Finally, the simulated profile of the rotating photoresist is measured to obtain the size of the rotating pattern. Specifically, the size of the rotating pattern may include the width, length, and height of the pattern.

[0106] As an optional embodiment, Figure 4 As shown, a schematic diagram of the comparison between the original photoresist simulation profile and the rotated photoresist simulation profile is provided. Among them, 4-a is the original photoresist simulation profile before rotation. After rotating it 90 degrees clockwise, 4-b can be obtained as the rotated photoresist simulation profile rotated 90 degrees. The size of the original photoresist simulation profile and the rotated photoresist simulation profile will not change under the ideal state of satisfying rotational symmetry, only the position will change.

[0107] Among them, rotational symmetry is used to characterize the property that after a figure is rotated around a certain point (the center of rotational symmetry) by a certain angle, the new figure obtained can still coincide with itself.

[0108] Through this embodiment, the rotation test layout and the rotation measurement data are input into the rotation photoresist simulation model to obtain the rotation photoresist simulation profile, and the rotation pattern size can be obtained by measuring the rotation photoresist simulation profile. In this way, it is possible to accurately determine whether there is a deviation between the pattern size obtained by performing photoresist imaging simulation using the optical modeling parameters after rotating the target angle and the optical modeling parameters before rotation, so as to accurately verify whether the photoresist simulation model to be evaluated conforms to the rotational symmetry.

[0109] As an optional embodiment, in the case where the optical modeling parameters in the optical modeling file are rotated to multiple target angles;

[0110] S105 may specifically include:

[0111] According to the size differences corresponding to the target angles, the number of target difference values ​​whose size differences are less than a preset difference threshold is determined;

[0112] Divide the number of target differences by the total number of size differences to get the target frequency;

[0113] When the target frequency is greater than a preset frequency threshold, it is determined that the photoresist simulation model to be evaluated does not have an overfitting phenomenon.

[0114] In this embodiment, the target difference number is used to represent the number of size differences whose size differences are less than the preset difference threshold, that is, the number of size differences that meet the rotational symmetry. The target frequency is used to represent the pass rate of each size difference.

[0115] As an example, the server predetermines a preset difference threshold and a preset frequency threshold according to process requirements and an acceptable error range.

[0116] Then, for each size difference corresponding to the target angle, the number of size differences less than the preset difference threshold is counted, that is, the target difference number is obtained. Then, the number of size differences corresponding to all target angles is counted, that is, the total number of size differences is obtained.

[0117] Then, the number of target differences is divided by the total number of size differences to obtain the target frequency. The target frequency reflects the consistency of the size of the rotated figure with the size of the reference figure at multiple target angles.

[0118] Finally, the target frequency is compared with the preset frequency threshold. If the target frequency is greater than the preset frequency threshold, it is considered that the photoresist simulation model to be evaluated does not have overfitting. This is because it means that the size of the rotated pattern of the model at multiple target angles is highly consistent with the size of the reference pattern, indicating that the model has good generalization ability.

[0119] If the target frequency is less than or equal to the preset frequency threshold, the photoresist simulation model to be evaluated is considered to be overfitted, because this means that the size of the rotated pattern of the model at multiple target angles is inconsistent with the size of the reference pattern, indicating that the model does not have good generalization ability.

[0120] Through this embodiment, the size of the rotated pattern at multiple rotation angles is compared with the size of the reference pattern, so as to evaluate whether the photoresist simulation model to be evaluated has an overfitting phenomenon, thereby avoiding contingency and improving the evaluation accuracy of the photoresist simulation model to be evaluated.

[0121] Evaluation method based on photoresist simulation model. Accordingly, the present application also provides a specific embodiment of an evaluation device for a photoresist simulation model.

[0122] like Figure 5 As shown, the evaluation device 500 of the photoresist simulation model provided in the embodiment of the present application includes a parameter acquisition module 510, a model construction module 520, a size determination module 530, a difference determination module 540 and a model evaluation module 550.

[0123] The parameter acquisition module 510 is used to acquire photoresist parameters and an optical modeling file of the photoresist simulation model to be evaluated, wherein the optical modeling file includes original optical modeling parameters used to construct the photoresist simulation model to be evaluated.

[0124] The model building module 520 is used to build a rotational photoresist simulation model according to the photoresist parameters and the optical modeling file. The rotational photoresist simulation model is a model for performing photoresist imaging simulation on the rotational optical modeling parameters after the original optical modeling parameters are rotated by a target angle.

[0125] The size determination module 530 is used to input the rotation optical modeling parameters into the rotation photoresist simulation model to obtain the rotation pattern size.

[0126] The difference determination module 540 is used to compare the size of the rotated pattern with the size of the reference pattern to obtain a size difference. The reference pattern size is the pattern size obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated.

[0127] The model evaluation module 550 is used to evaluate whether the photoresist simulation model to be evaluated has an overfitting phenomenon according to the size difference.

[0128] As an optional embodiment, the model building module 520 may include the following units:

[0129] A parameter rotation unit, used to rotate the original optical modeling parameters in the optical modeling file by at least one target angle to obtain the rotated optical modeling parameters after being rotated by the target angle;

[0130] A model building unit, used for performing optical simulation on rotational optical modeling parameters and building a rotational optical simulation model;

[0131] The model building unit is also used to build a rotating photoresist simulation model according to the photoresist parameters of the photoresist simulation model to be evaluated and the rotating optical simulation model.

[0132] As an optional embodiment, the rotation optical modeling parameters include a rotation test layout, rotation measurement data, and a rotation test light source;

[0133] The model building unit can include the following subunits:

[0134] A coefficient acquisition subunit is used to obtain a rotation cross-sensing coefficient corresponding to a rotation test light source, and the rotation cross-sensing coefficient is used to measure the mutual interference degree of the optical signals corresponding to the rotation test pattern during the transmission process;

[0135] The model building subunit is used to perform optical simulation on the rotation test layout, rotation measurement data and rotation cross-sensing coefficients to build a rotation optical simulation model.

[0136] As an optional embodiment, the coefficient acquisition subunit is specifically used for:

[0137] Determine, according to the rotating test light source, a first light source parameter and a second light source parameter corresponding to the rotating test light source, wherein the first light source parameter is a light source parameter whose corresponding first parameter value will change when the original test light source is rotated, and the second light source parameter is a light source parameter whose corresponding second parameter value will not change when the original test light source is rotated;

[0138] According to the target angle corresponding to the rotating test light source, a first parameter value corresponding to the first light source parameter is updated to obtain a first updated parameter value;

[0139] The rotation cross-sensing coefficient corresponding to the rotating test light source is determined according to the first updated parameter value and the second parameter value.

[0140] As an optional embodiment, the model building subunit is specifically used for:

[0141] Determine the rotation mask information according to the rotation test layout and the rotation measurement data;

[0142] The rotation mask information is convolved with the rotation cross sensing coefficient to obtain a rotational spatial image, which is used to characterize the light intensity distribution on the imaging surface corresponding to the rotational optical modeling parameters after the target angle is rotated;

[0143] According to the rotating spatial image, a rotating optical simulation model is constructed.

[0144] As an optional embodiment, the size determination module 530 may include the following units:

[0145] A profile generating unit, used for inputting the rotation test layout and the rotation measurement data into the rotation photoresist simulation model to obtain the rotation photoresist simulation profile;

[0146] The size determination unit is used to determine the size of the rotation pattern according to the simulation profile of the rotation photoresist.

[0147] As an optional embodiment, in the case where the optical modeling parameters in the optical modeling file are rotated to multiple target angles;

[0148] The model evaluation module 550 may include the following units:

[0149] A quantity determination unit, configured to determine the number of target difference values ​​whose size difference is less than a preset difference threshold value according to the size difference values ​​corresponding to each target angle;

[0150] A frequency calculation unit, used for dividing the number of target difference values ​​by the total number of size differences to obtain a target frequency;

[0151] The model evaluation unit is used to determine whether the photoresist simulation model to be evaluated has no overfitting phenomenon when the target frequency is greater than a preset frequency threshold.

[0152] Evaluation method based on photoresist simulation model. Accordingly, the present application also provides a specific embodiment of an evaluation device for a photoresist simulation model.

[0153] Figure 6 A schematic diagram of the hardware structure of an evaluation device for a photoresist simulation model provided in an embodiment of the present application is shown.

[0154] The evaluation device of the photoresist simulation model may include a processor 601 and a memory 602 storing computer program instructions.

[0155] Specifically, the processor 601 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0156] The memory 602 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 602 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, the memory 602 may include a removable or non-removable (or fixed) medium. In appropriate cases, the memory 602 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 602 is a non-volatile solid-state memory.

[0157] The processor 601 implements any one of the photoresist simulation model evaluation methods in the above embodiments by reading and executing computer program instructions stored in the memory 602 .

[0158] In one example, the evaluation device of the photoresist simulation model may further include a communication interface 603 and a bus 610. Figure 6 As shown, the processor 601, the memory 602, and the communication interface 603 are connected via a bus 610 and communicate with each other.

[0159] The communication interface 603 is mainly used to implement communication between various modules, devices, layout units and / or equipment in the embodiments of the present application.

[0160] Bus 610 includes hardware, software or both, and the parts of the evaluation equipment of photoresist simulation model are coupled to each other.For example, but not limitation, bus may include accelerated graphics port (AGP) or other graphics bus, enhanced industrial standard architecture (EISA) bus, front side bus (FSB), hypertransport (HT) interconnection, industrial standard architecture (ISA) bus, infinite bandwidth interconnection, low pin count (LPC) bus, memory bus, micro channel architecture (MCA) bus, peripheral component interconnection (PCI) bus, PCI-Express (PCI-X) bus, serial advanced technology attachment (SATA) bus, video electronics standard association local (VLB) bus or other suitable bus or two or more of these combinations. In suitable cases, bus 610 may include one or more buses. Although the present application embodiment describes and shows specific bus, the application considers any suitable bus or interconnection.

[0161] In addition, in combination with the evaluation method of the photoresist simulation model in the above embodiment, the embodiment of the present application can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by the processor, any one of the evaluation methods of the photoresist simulation model in the above embodiment is implemented.

[0162] In addition, in combination with the evaluation method of the photoresist simulation model in the above-mentioned embodiment, the embodiment of the present application can provide a computer program product for implementation. When the instructions in the computer program product are executed by the processor of an electronic device, the electronic device executes the evaluation method of the photoresist simulation model provided by any aspect of the above-mentioned embodiment of the present application.

[0163] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0164] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments that are used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0165] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0166] Aspects of the present disclosure are described above with reference to the flowchart and / or block diagram of the method, device (system) and computer program product according to the embodiment of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the function / action specified in one or more boxes of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit. It can also be understood that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can also be implemented by dedicated hardware that performs a specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions.

[0167] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process of the system, module and layout unit described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A method for evaluating a photoresist simulation model, characterized in that: include: Acquire photoresist parameters and an optical modeling file of a photoresist simulation model to be evaluated, wherein the optical modeling file includes original optical modeling parameters used to construct the photoresist simulation model to be evaluated; According to the photoresist parameters and the optical modeling file, a rotational photoresist simulation model is constructed, wherein the rotational photoresist simulation model is a model for performing photoresist imaging simulation on the rotational optical modeling parameters after the original optical modeling parameters are rotated by a target angle; Inputting the rotational optical modeling parameters into the rotational photoresist simulation model to obtain the rotational pattern size; Comparing the size of the rotated pattern with the size of a reference pattern to obtain a size difference, wherein the reference pattern size is the pattern size obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated; According to the size difference, it is evaluated whether the photoresist simulation model to be evaluated has an overfitting phenomenon.

2. The method according to claim 1, characterized in that The step of constructing a rotating photoresist simulation model according to the photoresist parameters and the optical modeling file comprises: Rotating the original optical modeling parameters in the optical modeling file by at least one target angle to obtain rotated optical modeling parameters after being rotated by the target angle; Performing optical simulation on the rotational optical modeling parameters to construct a rotational optical simulation model; A rotating photoresist simulation model is constructed according to the photoresist parameters of the photoresist simulation model to be evaluated and the rotating optical simulation model.

3. The method according to claim 2, characterized in that The rotational optical modeling parameters include a rotational test layout, rotational measurement data, and a rotational test light source; The optical simulation of the rotational optical modeling parameters to construct a rotational optical simulation model includes: Obtaining a rotation cross-sensing coefficient corresponding to the rotation test light source, wherein the rotation cross-sensing coefficient is used to measure the mutual interference degree of the optical signals corresponding to the rotation test pattern during the transmission process; Optical simulation is performed on the rotation test layout, the rotation measurement data and the rotation cross-sensing coefficient to construct the rotation optical simulation model.

4. The method according to claim 3, characterized in that The obtaining of the rotation cross-sensing coefficient corresponding to the rotating test light source comprises: Determine, according to the rotating test light source, a first light source parameter and a second light source parameter corresponding to the rotating test light source, wherein the first light source parameter is a light source parameter whose corresponding first parameter value will change when the original test light source is rotated, and the second light source parameter is a light source parameter whose corresponding second parameter value will not change when the original test light source is rotated; According to the target angle corresponding to the rotating test light source, a first parameter value corresponding to the first light source parameter is updated to obtain a first updated parameter value; The rotation cross-sensing coefficient corresponding to the rotating test light source is determined according to the first updated parameter value and the second parameter value.

5. The method according to claim 3, characterized in that: The optical simulation of the rotation test layout, the rotation measurement data and the rotation cross-sensing coefficient to construct the rotation optical simulation model includes: Determining rotation mask information according to the rotation test layout and the rotation measurement data; Performing a convolution operation on the rotation mask information and the rotation cross sensing coefficient to obtain a rotation aerial image, wherein the rotation aerial image is used to characterize the light intensity distribution on the imaging surface corresponding to the rotation optical modeling parameters after rotating the target angle; The rotational optical simulation model is constructed according to the rotational aerial image.

6. The method according to claim 1, characterized in that The step of inputting the rotation optical modeling parameters into the rotation photoresist simulation model to obtain the rotation graphic size comprises: Inputting the rotation test layout and the rotation measurement data into the rotation photoresist simulation model to obtain a rotation photoresist simulation profile; The size of the rotated pattern is determined according to the simulated profile of the rotated photoresist.

7. The method according to any one of claims 1 to 6, characterized in that: In the case where the optical modeling parameters in the optical modeling file are rotated by a plurality of target angles; The step of evaluating, according to the size difference, whether the photoresist simulation model to be evaluated has an overfitting phenomenon includes: Determine, according to the size differences corresponding to the target angles, the number of target difference values ​​whose size differences are less than a preset difference threshold; Dividing the target difference number by the total number of size differences to obtain a target frequency; When the target frequency is greater than a preset frequency threshold, it is determined that there is no overfitting phenomenon in the photoresist simulation model to be evaluated.

8. An electronic device, characterized in that: The device comprises: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, the method for evaluating the photoresist simulation model according to any one of claims 1 to 7 is implemented.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the method for evaluating the photoresist simulation model according to any one of claims 1 to 7 is implemented.

10. A computer program product, characterized in that When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the method for evaluating a photoresist simulation model as described in any one of claims 1 to 7.

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