Method, device, medium and product for evaluating a photoresist simulation model

Abstract

The application discloses an evaluation method and device 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 of a photoresist simulation model to be evaluated and an optical modeling file, wherein the optical modeling file comprises original optical modeling parameters used for constructing the photoresist simulation model to be evaluated; 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 pattern size; comparing the rotary pattern size with a reference pattern size to obtain a size difference value, wherein the reference pattern size is a pattern size obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated; and evaluating whether the photoresist simulation model to be evaluated has an overfitting phenomenon according to the size difference value.

Description

Technical Field

[0001] This application belongs to the field of photolithography simulation technology, and in particular relates to an evaluation method, equipment, medium and product for photoresist simulation models. Background Technology

[0002] In integrated circuit manufacturing, the structure of high-performance chips is becoming increasingly complex, and the linewidth is constantly decreasing. As the linewidth decreases, the optical proximity effect causes the imaging difference between the photomask pattern and the photoresist to gradually increase. Therefore, correcting the impact of the optical proximity effect is crucial.

[0003] Existing methods utilize photoresist simulation models to correct for the influence of optical proximity effects during the photolithography process. However, in creating these simulation models, the selected optical modeling parameters often overemphasize certain directions of the test pattern, leading to overfitting of the simulation model to these overemphasized directions.

[0004] However, existing methods cannot accurately identify whether the created photoresist simulation model has overfitting, resulting in low accuracy in evaluating the photoresist simulation model. Summary of the Invention

[0005] This application provides a method, device, medium, and product for evaluating photoresist simulation models, which can improve the accuracy of photoresist simulation model evaluation.

[0006] One aspect of this application provides a method for evaluating a photoresist simulation model, comprising:

[0007] Obtain the photoresist parameters and optical modeling file of the photoresist simulation model to be evaluated. The optical modeling file includes the original optical modeling parameters used to construct the photoresist simulation model to be evaluated.

[0008] Based on the photoresist parameters and optical modeling files, a rotating photoresist simulation model is constructed. The rotating photoresist simulation model is a model for simulating photoresist imaging by rotating the original optical modeling parameters by the target angle.

[0009] The rotational optical modeling parameters are input into the rotational photoresist simulation model to obtain the dimensions of the rotational pattern;

[0010] The size of the rotated graphic is compared with the size of the reference graphic to obtain the size difference. The size of the reference graphic is the size of the graphic obtained by inputting the original optical modeling parameters into the simulation model of the photoresist to be evaluated.

[0011] Based on the size difference, assess whether the simulation model of the photoresist to be evaluated exhibits overfitting.

[0012] In an aspect of the embodiments of the present application, an evaluation device for a photoresist simulation model is provided, which comprises:

[0013] a parameter acquisition module, configured to acquire photoresist parameters of a photoresist simulation model to be evaluated and an optical modeling file, the optical modeling file comprising original optical modeling parameters used for constructing the photoresist simulation model to be evaluated;

[0014] a model construction module, configured to construct a rotary photoresist simulation model according to the photoresist parameters and the optical modeling file, the rotary photoresist simulation model being a model for photoresist imaging simulation of rotary optical modeling parameters after a target angle of rotation of the original optical modeling parameters;

[0015] a size determination module, configured to input the rotary optical modeling parameters into the rotary photoresist simulation model to obtain a rotary pattern size;

[0016] a difference determination module, configured to compare the rotary pattern size with a reference pattern size to obtain a size difference, the reference pattern size being a pattern size obtained by inputting the original optical modeling parameters into the photoresist simulation model to be evaluated;

[0017] a model evaluation module, configured to evaluate whether the photoresist simulation model to be evaluated has an overfitting phenomenon according to the size difference.

[0018] In an aspect of the embodiments of the present application, an electronic device is provided, which comprises a memory and a program or instruction stored in the memory and executable on a processor, and the program or instruction is executed by the processor to implement the evaluation method for the photoresist simulation model provided in any one of the aspects of the embodiments of the present application.

[0019] In an aspect of the embodiments of the present application, a readable storage medium is provided, and the readable storage medium stores a program or instruction, and the program or instruction is executed by a processor to implement the evaluation method for the photoresist simulation model provided in any one of the aspects of the embodiments of the present application.

[0020] In an aspect of the embodiments of the present application, a computer program product is provided, and instructions in the computer program product are executed by a processor of an electronic device to enable the electronic device to perform the evaluation method for the photoresist simulation model provided in any one of the aspects of the embodiments of the present application.

[0021] The evaluation method of the photoresist simulation model provided in the embodiments of the present application comprises the following steps: constructing a rotating photoresist simulation model according to the photoresist parameters of the photoresist simulation model to be evaluated and the optical modeling file, and performing photoresist imaging simulation on the rotating optical modeling parameters after the original optical modeling parameters are rotated by a target angle. In this way, through the rotating photoresist simulation model, it can be determined whether there is a deviation between the graphic size obtained by performing photoresist imaging simulation on the optical modeling parameters after the target angle is rotated and the graphic size obtained by performing photoresist imaging simulation on the optical modeling parameters before the target angle is rotated, so as to verify 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 can be accurately determined whether the photoresist simulation model to be evaluated will appear overfitting. In this way, the embodiments of the present application can accurately identify whether the photoresist simulation model to be evaluated has overfitting phenomenon, and improve the accuracy of the evaluation of the photoresist simulation model. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments of the present application will be briefly introduced. Those skilled in the art can obtain other drawings according to these drawings without creating any creative labor.

[0023] Figure 1 is a flowchart of the evaluation method of the photoresist simulation model provided in an embodiment of the present application;

[0024] Figure 2 is a schematic diagram of the first kind of original optical modeling parameters being rotated to obtain rotating optical modeling parameters;

[0025] Figure 3 is a schematic diagram of the second kind of original optical modeling parameters being rotated to obtain rotating optical modeling parameters;

[0026] Figure 4 is a comparison schematic diagram of the original photoresist simulation profile and the rotating photoresist simulation profile provided in an embodiment of the present application;

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

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

[0029] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0030] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

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

[0032] It should be noted that in the embodiments of this application, certain software, components, models and other existing solutions in the industry may be mentioned. These should be regarded as exemplary and are only intended to illustrate the feasibility of implementing the technical solution of this application. However, it does not mean that the applicant has used or necessarily used the solution.

[0033] Existing methods utilize photoresist simulation models to correct for the influence of optical proximity effects during the photolithography process. However, in creating these simulation models, the selected optical modeling parameters often overemphasize certain directions of the test pattern, leading to overfitting of the simulation model to these overly dominant directions. Furthermore, existing methods cannot accurately identify overfitting issues in the created photoresist simulation models, resulting in low accuracy in evaluating them.

[0034] The purpose of the present application is to provide a photoresist simulation model evaluation method, device, medium and product. The photoresist simulation model evaluation method provided by the embodiments of the present application comprises the following steps: constructing a rotary photoresist simulation model according to the photoresist parameters of the photoresist simulation model to be evaluated and an optical modeling file, and performing photoresist imaging simulation on the rotary optical modeling parameters after the original optical modeling parameters are rotated by a target angle. In this way, by using the rotary photoresist simulation model, it can be determined whether there is a deviation between the pattern sizes obtained by respectively performing photoresist imaging simulation on the optical modeling parameters after the target angle is rotated and the optical modeling parameters before the rotation, so as to verify 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 can be accurately determined whether the photoresist simulation model to be evaluated will appear overfitting. In this way, the embodiments of the present application can accurately identify whether the photoresist simulation model to be evaluated has overfitting phenomenon, thereby improving the accuracy of the evaluation of the photoresist simulation model.

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

[0036] Figure 1 A flowchart of a photoresist simulation model evaluation method is provided. The photoresist simulation model evaluation method can be applied to a server. The photoresist simulation model evaluation method can comprise the following S101 to S104.

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

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

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

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

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

[0042] In this embodiment, the rotated optical modeling parameters are used to represent new parameters obtained after the original optical modeling parameters are rotated by a target angle. The target angle is a preset value, and for example, the target angle can be 90 degrees.

[0043] The rotated photoresist simulation model is a model for photoresist imaging simulation of the rotated optical modeling parameters.

[0044] As an example, after the server obtains 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 corresponding rotated optical modeling parameters. Then, based on the rotated optical modeling parameters and the photoresist parameters, the server corrects the to-be-evaluated photoresist simulation model to construct a rotated photoresist simulation model.

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

[0046] In this embodiment, the rotated pattern size is used to represent the size of the pattern profile generated by simulation according to the rotated optical modeling parameters.

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

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

[0049] In this embodiment, the reference pattern size refers to the size of the pattern profile obtained by inputting the original optical modeling parameters into the to-be-evaluated photoresist simulation model. It represents the imaging effect of the photoresist under the standard condition without rotation.

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

[0051] As an example, the server inputs the original optical modeling parameters into the to-be-evaluated photoresist simulation model for simulation operation to obtain a reference pattern size corresponding to the original optical modeling parameters. Then, the rotated pattern size is compared with the reference pattern size to calculate a size difference therebetween.

[0052] In S105, whether the to-be-evaluated photoresist simulation model has overfitting is evaluated according to the size difference.

[0053] In this embodiment, overfitting means that the to-be-evaluated photoresist simulation model relies too much 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 to-be-evaluated photoresist simulation model performs well on the original optical modeling parameters, but the rotated photoresist simulation model associated with the to-be-evaluated photoresist simulation model performs poorly on the rotated optical modeling parameters, it is considered that the to-be-evaluated photoresist simulation model has overfitting.

[0055] As an example, in a case where the size difference is greater than or equal to a preset difference threshold, i.e., in a case where the rotated pattern size and the reference pattern size have a large difference, it is determined that the to-be-evaluated photoresist simulation model has overfitting.

[0056] In a case where the size difference is less than the preset difference threshold, i.e., in a case where the rotated pattern size and the reference pattern size have a small difference, it is determined that the to-be-evaluated photoresist simulation model does not have overfitting.

[0057] In the method for evaluating a photoresist simulation model provided in this embodiment, a rotated photoresist simulation model is constructed according to the photoresist parameters of the to-be-evaluated photoresist simulation model and the optical modeling file, and is used for photoresist imaging simulation on the rotated optical modeling parameters after the original optical modeling parameters are rotated by a target angle. In this way, through the rotated photoresist simulation model, it can be accurately determined whether there is a deviation between the pattern sizes obtained by respectively performing photoresist imaging simulation on the optical modeling parameters after the target angle of rotation and the optical modeling parameters before rotation, so as to verify whether the to-be-evaluated photoresist simulation model conforms to rotational symmetry. By verifying whether the target photoresist simulation model conforms to rotational symmetry, it can be accurately judged whether the to-be-evaluated photoresist simulation model will have overfitting. In this way, through the rotated photoresist simulation model, the present embodiment can accurately identify whether the to-be-evaluated photoresist simulation model has overfitting, and improve the accuracy of evaluation on the photoresist simulation model.

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

[0059] 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 rotating by the target angle.

[0060] Optical simulation is performed on the rotating optical modeling parameters to construct a rotating optical simulation model;

[0061] Based on the photoresist parameters of the photoresist simulation model to be evaluated and the rotating optical simulation model, a rotating photoresist simulation model is constructed.

[0062] In this embodiment, there can be one or more target angles. When there are multiple target angles, they can be randomly selected within a preset angle range, or they can be selected systematically according to a preset selection strategy. For example, starting from 0 degrees, a target angle can be selected every 45 degrees clockwise until 360 degrees are reached, thus 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 the original optical modeling parameters from the optical modeling file, and then rotates each original optical modeling parameter according to the selected target angle using a rotation matrix, thereby obtaining the rotated optical modeling parameters after rotating by the target angle.

[0065] Next, acquire the target optical simulation software, such as Zemax or CODEV. Based on the rotational optical modeling parameters, use the target optical simulation software to set the parameters and obtain the rotational optical simulation model.

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

[0067] As another example, the original optical modeling parameters include the original test pattern and the original measurement data, while the rotated optical modeling parameters include the rotated test pattern and the rotated measurement data. Figure 2 As shown, a schematic diagram is provided for obtaining rotated optical modeling parameters by rotating the original optical modeling parameters. In this diagram, 2-a represents the original test pattern and original measurement data. Rotating it 90 degrees clockwise yields the rotated test pattern and rotated measurement data shown in 2-b.

[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 diagram of rotating original optical modeling parameters to obtain rotated optical modeling parameters is provided. Wherein, 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, the optical simulation is performed on the rotated optical modeling parameters to obtain the rotated optical simulation model, and then the rotated photoresist simulation model is constructed according to the photoresist parameters of the rotated optical simulation model and the photoresist simulation model to be evaluated. In this way, the rotated photoresist simulation model corresponding to the photoresist simulation model to be evaluated is constructed, so as to help accurately identify whether the photoresist simulation model to be evaluated has overfitting phenomenon through the rotated photoresist simulation model, and improve the accuracy of the photoresist simulation model evaluation.

[0070] As an optional embodiment, the rotated optical modeling parameters include the rotated test layout, the rotated metrology data, and the rotated test light source.

[0071] The optical simulation is performed on the rotated optical modeling parameters to construct the rotated optical simulation model, which can specifically include:

[0072] The rotated cross-sensing coefficient corresponding to the rotated test light source is obtained, and the rotated cross-sensing coefficient is used to measure the mutual interference degree of the optical signals corresponding to the rotated test layout in the transmission process.

[0073] The rotated optical simulation model is constructed by performing optical simulation on the rotated test layout, the rotated metrology data, and the rotated cross-sensing coefficient.

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

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

[0076] Then, the various test light sources are respectively started to emit light signals through the test layout. The light signals passing through the test layout are received by the light signal receiver, and the intensity, phase and other parameters thereof are recorded. According to the light signal data corresponding to the various test light sources, the cross-sensing coefficients of the various test light sources are respectively calculated. Specifically, the cross-sensing coefficients can be obtained by comparing the intensity difference and phase change between different light signals. Then, the various test light sources and the corresponding cross-sensing coefficients are generated into a cross-sensing coefficient table.

[0077] When it is necessary to construct a rotary optical simulation model corresponding to the rotary optical modeling parameter, the rotary test light source is compared with the cross-sensing coefficient table, so as to obtain the rotary cross-sensing coefficient corresponding to the rotary test light source.

[0078] Then, an initial optical simulation model is established by using a target optical simulation software, and then the information of the rotary test layout and the information of the rotary metrology data are imported into the initial optical simulation model. At the same time, the light signal interference parameters are set according to the rotary cross-sensing coefficient obtained in advance.

[0079] Then, the optical simulation model is run to simulate the transmission process of the light signal in the test layout, so as to obtain the simulation result. Finally, the optical simulation model is adjusted according to the simulation result, so as to obtain the final rotary optical simulation model.

[0080] Through the embodiment, the rotary cross-sensing coefficient corresponding to the rotary test light source is obtained, and the optical simulation is performed by using the rotary cross-sensing coefficient, so as to construct the rotary optical simulation model. In this way, the rotary optical simulation model is accurately constructed by using the rotary cross-sensing coefficient, so as to help further construct the rotary photoresist simulation model according to the rotary optical simulation model, accurately identify whether the to-be-evaluated photoresist simulation model has the overfitting phenomenon, and improve the accuracy of the evaluation of the photoresist simulation model.

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

[0082] According to the rotary test light source, a first light source parameter corresponding to a first parameter value that will change when the original test light source is rotated and a second light source parameter corresponding to a second parameter value that will not change when the original test light source is rotated are determined;

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

[0084] According to the first updated parameter value and the second parameter value, a rotation cross-sensing coefficient corresponding to the rotation test light source is determined.

[0085] In the embodiment, there are many light source parameters of the test light source. Among them, a part of the light source parameters will change with the rotation of the test light source, and the parameter values of this part of the parameters will also change. This part of the parameters is the first light source parameter, for example, the light source feature point coordinates and the light source polarization direction related to the generation of the cross-sensing coefficient.

[0086] Another part of the light source parameters will not change with the rotation of the test light source, and the parameter values of this part of the parameters will not change. This part of the parameters is the second light source parameter, for example, the light source wavelength.

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

[0088] Then, for the first light source parameter, the corresponding parameter value is updated according to the target angle of rotation to obtain the first updated parameter value; and for the second light source parameter, the 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 updated parameter value and the second parameter value to obtain the rotation cross-sensing coefficient of the rotation test light source.

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

[0091] As an optional embodiment, the rotation test layout, the rotation metrology data, and the rotation cross-sensing coefficient are optically simulated to construct a rotation optical simulation model, which can specifically include:

[0092] According to the rotation test layout and the rotation metrology data, rotation mask information is determined.

[0093] The rotation mask information and the rotation cross-sensing coefficient are convolved to obtain a rotation aerial image, and the rotation aerial image is used to represent the light intensity distribution on the imaging surface corresponding to the rotation optical modeling parameter after the rotation target angle.

[0094] According to the rotation aerial image, a rotation 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 rotation target angle. The rotation mask information can be a function or a matrix describing the change of the optical parameters during the rotation target angle.

[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 can be different due to the design of the test layout, the characteristics of the rotation angle, and other factors. For example, the rotation mask information can be represented in the form of a matrix.

[0097] Then, the rotation mask information is convolved with the rotation cross-sensing coefficient to obtain a rotation aerial image. The rotation aerial image can directly show the influence of the imaging quality of the optical system during the rotation target angle. For example, as the rotation angle increases, the light intensity gradually weakens, and the image shift phenomenon appears.

[0098] Finally, according to the rotation aerial image, a rotation optical simulation model is constructed using an optical simulation software or tool.

[0099] Through this embodiment, the rotation test layout, the rotation measurement data, and the rotation cross-sensing coefficient are optically simulated to construct a rotation optical simulation model. In this way, it is helpful to further construct a rotation photoresist simulation model according to the rotation optical simulation model, so as to accurately identify whether the to-be-evaluated photoresist simulation model has an overfitting phenomenon, and improve the accuracy of the evaluation of the photoresist simulation model.

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

[0101] The rotation test layout and the rotation measurement data are input into the rotation photoresist simulation model to obtain a rotation photoresist simulation profile.

[0102] According to the rotation photoresist simulation profile, a rotation pattern size is determined.

[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 will perform simulation calculation according to the input data and the preset photoresist parameters.

[0104] After the simulation calculation, the rotation photoresist simulation model outputs a simulation profile of the rotation photoresist. The simulation profile of the rotation photoresist is the expected shape of the photoresist after exposure and development in the photoetching process.

[0105] Finally, the simulation profile of the rotation photoresist is measured to obtain a rotation pattern size. Specifically, the rotation pattern size can include the width, length, and height of the pattern.

[0106] As an optional embodiment, as shown in Figure 4 FIG. 4 shows a schematic diagram of a comparison between an original photoresist simulation profile and a rotated photoresist simulation profile. Wherein, 4-a is the original photoresist simulation profile before rotation, and 4-b is the rotated photoresist simulation profile after rotating the original photoresist simulation profile 90 degrees clockwise. The size of the original photoresist simulation profile and the rotated photoresist simulation profile will not change under the ideal state of rotational symmetry, only the position changes.

[0107] Wherein, the rotational symmetry is used to represent the property that a new figure obtained by rotating a figure around a point (rotational symmetry center) by a certain angle can still coincide with itself.

[0108] In this embodiment, the rotated test layout and the rotation measurement data are input into the rotated photoresist simulation model to obtain the rotated photoresist simulation profile. The rotated photoresist simulation profile is measured to obtain the rotated figure size. In this way, it can be determined whether there is a deviation between the optical modeling parameters after the rotation target angle and the optical modeling parameters before the rotation, respectively, and the figure size obtained by photoresist imaging simulation, so as to accurately verify whether the to-be-evaluated photoresist simulation model meets the rotational symmetry.

[0109] As an optional embodiment, in the case of rotating the optical modeling parameters in the optical modeling file by multiple target angles;

[0110] S105 can specifically include:

[0111] According to the size difference values corresponding to each target angle, determine the number of target difference values whose size difference values are less than a preset difference threshold value;

[0112] Divide the number of target difference values by the total number of size difference values to obtain a target frequency;

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

[0114] In this embodiment, the number of target difference values represents the number of size difference values that are less than the preset difference threshold value, that is, the number of size difference values that meet the rotational symmetry. The target frequency represents the qualified rate of each size difference value.

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

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

[0117] Then, the target difference number is divided by the total number of size difference values to obtain the target frequency. The target frequency reflects the consistency of the rotated pattern size and the reference pattern size under 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 overfitting phenomenon of the evaluated photoresist simulation model does not exist. Because this means that the rotated pattern size and the reference pattern size of the model under multiple target angles are highly consistent, indicating that the model has good generalization ability.

[0119] If the target frequency is less than or equal to the preset frequency threshold, it is considered that the overfitting phenomenon of the evaluated photoresist simulation model exists. Because this means that the rotated pattern size and the reference pattern size of the model under multiple target angles are inconsistent, indicating that the model does not have good generalization ability.

[0120] Through the embodiment, the rotated pattern size and the reference pattern size under multiple rotation angles are compared to evaluate whether the evaluated photoresist simulation model has an overfitting phenomenon. Occasionality can be avoided, and the evaluation accuracy of the evaluated photoresist simulation model is improved.

[0121] The evaluation method of the photoresist simulation model is based on the photoresist simulation model. Accordingly, the application also provides specific embodiments of the evaluation device of the photoresist simulation model.

[0122] As shown in Figure 5 The evaluation device 500 of the photoresist simulation model provided by the embodiment of the 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 configured to acquire photoresist parameters of an evaluated photoresist simulation model and an optical modeling file. The optical modeling file includes original optical modeling parameters used to construct the evaluated photoresist simulation model.

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

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

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

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

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

[0129] The parameter rotation unit is configured to rotate the original optical modeling parameter in the optical modeling file by at least one target angle to obtain a rotated optical modeling parameter after the target angle.

[0130] The model construction unit is configured to perform optical simulation on the rotated optical modeling parameter to construct a rotated optical simulation model.

[0131] The model construction unit is further configured to construct a rotated photoresist simulation model according to a photoresist parameter of the to-be-evaluated photoresist simulation model and the rotated optical simulation model.

[0132] As an optional embodiment, the rotated optical modeling parameter includes a rotated test layout, rotated metrology data, and a rotated test light source.

[0133] The model construction unit can include the following sub-units:

[0134] The coefficient acquisition sub-unit is configured to acquire a rotated cross-sensing coefficient corresponding to the rotated test light source, the rotated cross-sensing coefficient being used to measure a mutual interference degree of optical signals corresponding to the rotated test layout in a transmission process.

[0135] The model construction sub-unit is configured to perform optical simulation on the rotated test layout, the rotated metrology data, and the rotated cross-sensing coefficient to construct the rotated optical simulation model.

[0136] As an optional embodiment, the coefficient acquisition sub-unit is specifically configured to:

[0137] determine, according to the rotated test light source, a first light source parameter and a second light source parameter corresponding to the rotated test light source, the first light source parameter being a light source parameter whose first parameter value corresponding to the original test light source changes after rotation, and the second light source parameter being a light source parameter whose second parameter value corresponding to the original test light source does not change after rotation;

[0138] update the first parameter value corresponding to the first light source parameter according to the target angle corresponding to the rotated test light source to obtain a first updated parameter value;

[0139] According to the first update parameter value and the second parameter value, a rotation cross-sensing coefficient corresponding to the rotation test light source is determined.

[0140] As an optional embodiment, the model construction subunit is specifically configured to:

[0141] According to the rotation test layout and the rotation metrology data, rotation mask information is determined.

[0142] The rotation mask information is convolved with the rotation cross-sensing coefficient to obtain a rotation aerial image, and the rotation aerial image is used to represent the light intensity distribution on an imaging surface corresponding to the rotation optical modeling parameter after the rotation target angle.

[0143] According to the rotation aerial image, a rotation optical simulation model is constructed.

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

[0145] The profile generation unit is configured to input the rotation test layout and the rotation metrology data into the rotation photoresist simulation model to obtain a rotation photoresist simulation profile.

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

[0147] As an optional embodiment, in the case of rotating the optical modeling parameter in the optical modeling file by a plurality of target angles;

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

[0149] The quantity determination unit is configured to determine the number of target difference values whose size difference values are less than a preset difference threshold according to the size difference values corresponding to each target angle.

[0150] The frequency calculation unit is configured to divide the number of target difference values by the total number of size difference values to obtain a target frequency.

[0151] The model evaluation unit is configured to determine that the photoresist simulation model to be evaluated does not have an overfitting phenomenon in the case that the target frequency is greater than a preset frequency threshold.

[0152] The evaluation method of the photoresist simulation model based on the photoresist simulation model. Accordingly, the present application also provides specific embodiments of the evaluation equipment of the photoresist simulation model.

[0153] Figure 6 The hardware structure schematic diagram of the evaluation equipment of the photoresist simulation model provided by the embodiments of the present application is shown.

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

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

[0156] The memory 602 can include a mass storage for data or instructions. By way of example and not limitation, the memory 602 can 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. The memory 602 can include removable or non-removable (or fixed) media, where appropriate. The memory 602 can be internal or external to the integrated gateway disaster recovery device, where appropriate. In particular embodiments, the memory 602 is non-volatile, solid-state memory.

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

[0158] In one example, the photoresist simulation model evaluation device can further include a communication interface 603 and a bus 610. As shown, the processor 601, the memory 602, and the communication interface 603 are connected through the bus 610 and complete communication among each other. Figure 6

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

[0160] ​Bus 610 includes hardware, software, or both, to couple components of the photoresist simulation model evaluation device to each other in communication. While Figure 6 provides one non-limiting example of a bus, it is contemplated that other bus configurations can be used in other embodiments. For example, the bus can be implemented as an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a HyperTransport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an InfiniBand (IB) interconnect, a Low Pin Count (LPC) bus, a memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local (VLB) bus, or another suitable bus or a combination of two or more of these. Where appropriate, bus 610 can include one or more buses. Although this application describes and illustrates a particular bus, this application contemplates any suitable bus or interconnect.

[0161] In addition, the photoresist simulation model evaluation method in the above embodiments can be implemented by a computer storage medium. The computer storage medium stores computer program instructions; the computer program instructions are executed by a processor to implement any of the photoresist simulation model evaluation methods in the above embodiments.

[0162] In addition, the photoresist simulation model evaluation method in the above embodiments can be implemented by a computer program product. The instructions in the computer program product are executed by a processor of an electronic device to enable the electronic device to perform the photoresist simulation model evaluation method provided by any of the above embodiments of the application.

[0163] It is to be understood that the application is not limited to the particular configurations and processes described and illustrated herein. Detailed descriptions of known methods are omitted so as not to obscure the description of the present application. In the above embodiments, several specific steps are described and illustrated as examples. However, the method processes of the present application are not limited to the specific steps described and illustrated, and one skilled in the art can make various changes, modifications and additions, or change the order of the steps, after understanding the spirit of the present application.

[0164] The functions noted in the description of the structural block diagrams above can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application specific integrated circuits (ASICs), appropriate firmware, plug-ins, functional cards, and the like. When implemented in software, the elements of the present application are program or code segments that are used to perform the required tasks. The program or code segments can be stored in a machine-readable medium or transmitted through a data signal carried in a carrier wave over a transmission medium or communication link. A "machine-readable medium" includes any medium that can store or transport 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, fiber optic media, radio frequency (RF) links, and the like. The code segments can be downloaded via computer networks such as the Internet, intranets, and the like.

[0165] It is also important to note that the examples mentioned in the present application describe some methods or systems based on a series of steps or devices. However, the present application is not limited to the order of the steps mentioned above, that is, the steps can be performed in the order mentioned in the examples, or in an order different from the examples, or several steps can be performed simultaneously.

[0166] The computer program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other processing device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other processing device to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. These computer program instructions can also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other processing device to operate in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the functions / acts specified in the flowchart and / or block diagram block or blocks. The computer program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other processing device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other processing device to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0167] The above merely describes a specific implementation of the present application. Those skilled in the art can clearly understand the specific working processes of the system, modules and layout units described above for the convenience and brevity of description, and can refer to the corresponding processes in the foregoing method embodiments, which will not be described herein again. It should be understood that the protection scope of the present application is not limited to this, and any person skilled in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the present application, and these modifications or replacements should be covered within the protection scope of the present application.

Claims

1. A method for evaluating a photoresist simulation model, characterized in that, include: Obtain the photoresist parameters and optical modeling file of the photoresist simulation model to be evaluated. The optical modeling file includes the original optical modeling parameters used to construct the photoresist simulation model to be evaluated. Based on the photoresist parameters and the optical modeling file, a rotating photoresist simulation model is constructed. The rotating photoresist simulation model is a model for simulating photoresist imaging by rotating the original optical modeling parameters by a target angle. The rotational optical modeling parameters are input into the rotational photoresist simulation model to obtain the rotational pattern dimensions; The size of the rotated graphic is compared with the size of the reference graphic to obtain the size difference. The size of the reference graphic is the size of the graphic obtained by inputting the original optical modeling parameters into the simulation model of the photoresist to be evaluated. Based on the size difference, assess whether the photoresist simulation model under evaluation exhibits overfitting. The step of constructing a rotating photoresist simulation model based on the photoresist parameters and the optical modeling file includes: The original optical modeling parameters in the optical modeling file are rotated by at least one target angle to obtain the rotated optical modeling parameters after rotating by the target angle. The rotated optical modeling parameters include the rotated test pattern, the rotated measurement data, and the rotated test light source. Obtain the rotational cross sensing coefficient corresponding to the rotating test light source. The rotational cross sensing coefficient is used to measure the degree of mutual interference of the optical signals corresponding to the rotating test pattern during transmission. Optical simulations are performed on the rotation test layout, the rotation measurement data, and the rotation cross sensing coefficients to construct a rotation optical simulation model; Based on the photoresist parameters of the photoresist simulation model to be evaluated and the rotating optical simulation model, a rotating photoresist simulation model is constructed.

2. The method according to claim 1, characterized in that, The step of obtaining the rotational cross sensing coefficient corresponding to the rotating test light source includes: Based on the rotating test light source, determine the first light source parameter and the second light source parameter corresponding to the rotating test light source. The first light source parameter is the light source parameter whose first parameter value will change when the original test light source is rotated. The second light source parameter is the light source parameter whose second parameter value will not change when the original test light source is rotated. Based on the target angle corresponding to the rotating test light source, the first parameter value corresponding to the first light source parameter is updated to obtain the first updated parameter value; The rotational cross sensing coefficient corresponding to the rotating test light source is determined based on the first updated parameter value and the second parameter value.

3. The method according to claim 1, characterized in that, The step of performing optical simulation on the rotating test layout, the rotating measurement data, and the rotating cross-sensing coefficients to construct the rotating optical simulation model includes: Based on the rotation test layout and the rotation measurement data, determine the rotation mask information; The rotation mask information is convolved with the rotation cross sensing coefficient to obtain a rotation spatial image. The rotation spatial 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. Based on the rotating spatial image, construct the rotating optical simulation model.

4. The method according to claim 1, characterized in that, The step of inputting the rotational optical modeling parameters into the rotational photoresist simulation model to obtain the rotational pattern size includes: The rotation test pattern and rotation measurement data are input into the rotation photoresist simulation model to obtain the rotation photoresist simulation profile. The dimensions of the rotating pattern are determined based on the simulated profile of the rotating photoresist.

5. The method according to any one of claims 1-4, characterized in that, When rotating the optical modeling parameters in the optical modeling file by multiple target angles; The step of evaluating whether the photoresist simulation model under evaluation exhibits overfitting based on the size difference includes: Based on the size difference corresponding to each of the target angles, determine the number of target differences whose size difference is less than a preset difference threshold; Divide the number of target differences by the total number of size differences to obtain the target frequency; If the target frequency is greater than a preset frequency threshold, it is determined that the photoresist simulation model to be evaluated does not exhibit overfitting.

6. An electronic device, characterized in that, The device includes: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, it implements the evaluation method for the photoresist simulation model as described in any one of claims 1-5.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer program instructions, which, when executed by a processor, implement the evaluation method for the photoresist simulation model as described in any one of claims 1-5.

8. A computer program product, characterized in that, When the instructions in the computer program product are executed by the processor of the electronic device, the electronic device performs the evaluation method of the photoresist simulation model as described in any one of claims 1-5.

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