A method and device for measuring the thickness of a thin film, an electronic device and a readable storage medium

Abstract

The application provides a method and device for measuring film thickness, an electronic device and a readable storage medium. The method comprises: obtaining initial film thickness of each first measurement point in each to-be-measured film layer of a thin film; for each to-be-measured film layer, correcting the initial film thickness of each first measurement point of the to-be-measured film layer according to a corresponding target topography constraint library to obtain corrected film thickness of each first measurement point of the to-be-measured film layer, and the topography constraint library is used to characterize the topography feature of the film layer; constructing a simulation model of the to-be-measured film layer according to the corrected film thickness and the feature of the thin film; and determining the real film thickness of the to-be-measured film layer according to simulation data of the simulation model and theoretical data of the to-be-measured film layer. The application can obtain accurate film thickness of each to-be-measured film layer of the thin film.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of semiconductor, and particularly relates to a method and device for measuring film thickness, an electronic device and a readable storage medium. BACKGROUND

[0002] The working process of the existing method for measuring film thickness is to measure the film thickness of each measurement point of the film, model and data fit, so as to obtain the film thickness of each measurement point. However, if the film includes multiple film layers, there may be a mutual coupling relationship between the film layers, which may cause the film thickness measurement result of each film layer to be inaccurate. SUMMARY

[0003] The embodiments of the present application provide a method and device for measuring film thickness, an electronic device, a readable storage medium and a computer program product, which can solve the problem of inaccurate film thickness measurement result of the film layer.

[0004] In a first aspect, the embodiments of the present application provide a method for measuring film thickness, comprising:

[0005] obtaining initial film thicknesses of first measurement points in each to-be-measured film layer of a film;

[0006] for each to-be-measured film layer, correcting the initial film thicknesses of the first measurement points of the to-be-measured film layer according to a corresponding target topography constraint library to obtain corrected film thicknesses of the first measurement points of the to-be-measured film layer, the topography constraint library being used to represent topographic features of the film layer;

[0007] constructing a simulation model of the to-be-measured film layer according to the corrected film thicknesses and characteristics of the film;

[0008] determining a real film thickness of the to-be-measured film layer according to simulation data of the simulation model and theoretical data of the to-be-measured film layer.

[0009] Optionally, before obtaining the initial film thicknesses of each to-be-measured film layer, the method further comprises:

[0010] for each to-be-measured film layer, determining film thickness relative ratios of second measurement points of a preselected film layer according to measured film thicknesses of the second measurement points and corresponding reference film thicknesses, the preselected film layer being a standard film sample including one film layer;

[0011] generating a target topography constraint library of the to-be-measured film layer according to positions of the second measurement points and the corresponding film thickness relative ratios.

[0012] Optionally, the determining of the film thickness relative ratios of the second measurement points according to the measured film thicknesses of the second measurement points and the corresponding reference film thicknesses comprises:

[0013] inputting the thermal map of the preselected film layer into a generator of a GAN neural network to generate a plurality of to-be-judged thermal maps;

[0014] inputting the to-be-judged thermal map and the real thermal map of the film into a discriminator of the GAN neural network to obtain a target thermal map output by the discriminator, the target thermal map being the to-be-judged thermal map having a correlation greater than a preset correlation with the real thermal map;

[0015] determining a measured film thickness of each second measurement point of the preselected film layer according to the target thermal map;

[0016] determining a film thickness relative ratio of each second measurement point according to the measured film thickness of each second measurement point and a corresponding reference film thickness, the reference film thickness being a film thickness of a second measurement point of the real thermal map.

[0017] Optionally, the determining of the film thickness relative ratio of each second measurement point according to the measured film thickness of each second measurement point of the corresponding preselected film layer and the corresponding reference film thickness comprises:

[0018] randomly generating a plurality of to-be-screened thermal maps according to the real thermal map of the film;

[0019] screening a target thermal map from the plurality of to-be-screened thermal maps, the target thermal map being the to-be-screened thermal map having a correlation greater than a preset correlation with the real thermal map;

[0020] determining a measured film thickness of each second measurement point of the preselected film layer according to the target thermal map;

[0021] determining a film thickness relative ratio of each second measurement point according to the measured film thickness of each second measurement point and a corresponding reference film thickness, the reference film thickness being a film thickness of a second measurement point of the real thermal map.

[0022] Optionally, the generating of the target topography constraint library of the to-be-measured film layer according to the positions of each second measurement point and the corresponding film thickness relative ratio comprises:

[0023] generating an initial topography constraint library of the to-be-measured film layer according to the positions of each second measurement point and the corresponding film thickness relative ratio;

[0024] obtaining a rotation angle of the preselected film layer;

[0025] updating the initial topography constraint library according to the rotation angle to obtain an updated topography constraint library;

[0026] According to the film thickness relative ratio of each second measurement point of the updated topography constraint library, the updated topography constraint library is interpolated to obtain the target topography constraint library.

[0027] Optionally, the correcting the initial film thickness of each first measurement point of the to-be-measured film layer according to the corresponding target topography constraint library comprises:

[0028] For each first measurement point of each to-be-measured film layer, a target film thickness relative ratio is determined in the target topography constraint library according to the position of the first measurement point of the to-be-measured film layer.

[0029] The initial film thickness is corrected according to the target film thickness relative ratio.

[0030] Optionally, the constructing the simulation model of the to-be-measured film layer according to the corrected film thickness and the characteristics of the thin film comprises:

[0031] The simulation model is constructed according to the corrected film thickness of the to-be-measured film layer, the optical constant of each to-be-measured film layer of the thin film, the estimated thickness, and the film layer stacking order of the thin film, and the characteristics of the thin film include the film layer stacking order and the optical constant and the estimated thickness of each to-be-measured film layer.

[0032] In a second aspect, an embodiment of the present application provides a device for measuring film thickness, comprising:

[0033] A film thickness acquisition module is configured to acquire initial film thicknesses of to-be-measured film layers of a thin film.

[0034] A corrected film thickness module is configured to correct, for each to-be-measured film layer, the initial film thickness of each first measurement point of the to-be-measured film layer according to a corresponding target topography constraint library to obtain a corrected film thickness of each first measurement point of the to-be-measured film layer, wherein the topography constraint library represents a topographic feature of a film layer.

[0035] A model construction module is configured to construct a simulation model of the to-be-measured film layer according to the corrected film thickness and the characteristics of the thin film.

[0036] A film thickness determination module is configured to determine a real film thickness of the to-be-measured film layer according to simulation data of the simulation model and theoretical data of the to-be-measured film layer.

[0037] In a third aspect, an embodiment of the present application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor implements the method of any one of the above first aspect when executing the computer program.

[0038] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the method in any one of the first aspect.

[0039] In a fifth aspect, an embodiment of the present application provides a computer program product. When the computer program product is run on an electronic device, the electronic device is caused to perform the method in any one of the first aspect.

[0040] Compared with the prior art, the embodiment of the present application has the following beneficial effects:

[0041] The embodiment of the present application corrects the initial film thickness of each first measurement point of the to-be-measured film layer according to the corresponding target topography constraint library, obtains the corrected film thickness of each first measurement point of the to-be-measured film layer, adds topography constraints to the to-be-measured film layer, and obtains the corrected film thickness of the to-be-measured film layer.

[0042] The embodiment of the present application constructs a simulation model of the to-be-measured film layer according to the corrected film thickness and the characteristics of the thin film, considers the film thickness of each measurement point, and realizes the construction of a more accurate model by taking all the measurement points of the to-be-measured film layer as a whole. Then, the real film thickness of the to-be-measured film layer is determined according to the simulation data of the simulation model and the theoretical data of the to-be-measured film layer, so as to obtain the accurate film thickness of the to-be-measured film layer.

[0043] It can be understood that the beneficial effects of the above-mentioned second aspect to fifth aspect can be referred to the related description in the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0045] Figure 1 is the first flowchart of the method for measuring the film thickness of a thin film provided by an embodiment of the present application;

[0046] Figure 2 is the second flowchart of the method for measuring the film thickness of a thin film provided by an embodiment of the present application;

[0047] Figure 3 is the third flowchart of the method for measuring the film thickness of a thin film provided by an embodiment of the present application;

[0048] Figure 4 is a structural schematic diagram of the device for measuring the film thickness of a thin film provided by an embodiment of the present application;

[0049] Figure 5 FIG. 1 is a structural schematic diagram of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0050] In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular sequences of acts, techniques, etc., in order to provide a thorough understanding of the present application. However, it will be apparent to those skilled in the art that the present application can be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known methods, devices, and circuits are omitted so as not to obscure the description of the present application with unnecessary detail.

[0051] It is to be understood that the terminology "includes", "has", "holds", "contains" or "comprising", "comprised of" or "comprising", as used in the specification and in the following claims, indicates the presence of the stated features, integers, steps, operations, elements, or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof.

[0052] It is also to be understood that the terminology "and / or" as used in the specification and in the following claims, indicates any combination of the associated listed items, as well as all possible combinations of the items.

[0053] As used in the specification and in the following claims, the term "if" can be interpreted as meaning "when" or "upon" or "in response to determining" or "in response to detecting" depending on the context. Similarly, the phrase "if it is determined" or "if [the described condition or event] is detected" can be interpreted as meaning "upon determining" or "in response to determining" or "upon detecting [the described condition or event]" or "in response to detecting [the described condition or event]" depending on the context.

[0054] In addition, in the description of the specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish descriptions, and cannot be understood as indicating or implying relative importance.

[0055] Reference within the specification of this application to "one embodiment" or "some embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. The appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in additional embodiments," and so on, in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily referring to some, but not all, embodiments. The terms "including," "comprising," "having," and variations thereof are meant to encompass the items listed thereafter, but do not exclude other items from also being present. Unless otherwise indicated, the terms "including," "comprising," "having," and variations thereof are meant to encompass the items listed thereafter, but do not exclude other items from also being present.

[0056] The existing method for measuring the film thickness of a thin film generally regards multiple measurement points of a film layer as independent. Correspondingly, the workflow is to measure the film thickness of each measurement point of the thin film, model, and fit data to obtain the film thickness of each measurement point. However, if the thin film includes multiple film layers, there can be a mutual coupling relationship between the film layers, which can cause the model established for the measurement point to have multiple solutions, so that multiple sets of film thicknesses are fitted for each measurement point, and finally the film thickness measurement results of each film layer can be inaccurate.

[0057] To solve the above problem, an embodiment of the present application provides a method for measuring the film thickness of a thin film, obtaining initial film thicknesses of each to-be-measured film layer of the thin film; for each to-be-measured film layer, correcting the initial film thicknesses of each first measurement point of the to-be-measured film layer according to a corresponding target topography constraint library to obtain corrected film thicknesses of each first measurement point of the to-be-measured film layer, the topography constraint library being used to characterize the topographic features of the film layer; constructing a simulation model of the to-be-measured film layer according to the corrected film thicknesses and the characteristics of the thin film; and determining the real film thickness of the to-be-measured film layer according to the simulation data of the simulation model and the theoretical data of the to-be-measured film layer to obtain an accurate real film thickness of the to-be-measured film layer.

[0058] Figure 1 FIG. 1 is a first flowchart of a method for measuring the film thickness of a thin film according to an embodiment of the present application.

[0059] As shown in FIG. 1, the method includes the following steps. Figure 1

[0060] S11: Obtain initial film thicknesses of each first measurement point in each to-be-measured film layer of the thin film.

[0061] In application, the thin film includes multiple film layers, i.e., the number of film layers is greater than 1.

[0062] S12: For each to-be-measured film layer, correct the initial film thicknesses of each first measurement point of the to-be-measured film layer according to a corresponding target topography constraint library to obtain corrected film thicknesses of each first measurement point of the to-be-measured film layer.

[0063] ​The topography constraint library is used to represent the topography characteristics of the film layer.

[0064] In application, each film layer of the thin film corresponds to a topography constraint library, i.e., each to-be-measured film layer corresponds to a target topography constraint library. The target topography constraint library is obtained in advance.

[0065] In general, the initial film thickness measured is inaccurate and needs to be corrected due to the cost and time consumption of the accurate film thickness measurement technology. The target topography constraint library of the to-be-measured film layer is added to correct the film thickness of each first measurement point of the to-be-measured film layer, so as to be closer to the real film thickness.

[0066] S13: According to the corrected film thickness and the characteristics of the thin film, a simulation model of the to-be-measured film layer is constructed.

[0067] In application, the amplitude ratio angle and the phase difference angle based on the general indirect measurement cannot be directly used, and the simulation model of the to-be-measured film layer needs to be constructed first. The parameters of the simulation model include the corrected film thickness of the to-be-measured film layer and the characteristics of the thin film.

[0068] S14: According to the simulation data of the simulation model and the theoretical data of the to-be-measured film layer, the real film thickness of the to-be-measured film layer is determined.

[0069] In a possible implementation, based on the parameters of the simulation model, the amplitude ratio angle Ψ and the phase difference value Δ corresponding to the simulation model are calculated according to the Fresnel equation, and then the three curves of the simulated OCD (Optical Critical Dimension) optical spectrum are calculated according to the amplitude ratio angle Ψ and the phase difference value Δ corresponding to the simulation model, the calculation formula being: N = cos2Ψ; N = sin2ΨcosΔ; S = sin2ΨsinΔ. The simulation data include N, C, and S.

[0070] In a possible implementation, the theoretical data of the to-be-measured film layer is obtained by an ellipsometric spectrum measurement method. Specifically, the ellipsometric spectrum is collected by the ellipsometric spectrum measurement method, the ellipsometric spectrum including the amplitude ratio angle Ψ and the phase difference value Δ, and then the three curves of the theoretical OCD optical spectrum are calculated according to the ellipsometric spectrum, the calculation formula being: N = cos2Ψ; C = sin2ΨcosΔ; S = sin2ΨsinΔ. The theoretical data include N, C, and S.

[0071] In application, the simulation data of the simulation model and the theoretical data of the to-be-measured film layer are fitted to obtain the real film thickness.

[0072] In a possible implementation, the parameters of the simulation model can be changed by an optimization method such as the gradient descent method to change the simulation data of the simulation model. When the difference between the simulation data and the theoretical data is minimum, the simulation data corresponding to the minimum difference and the theoretical data are fitted to obtain the real film thickness.

[0073] It can be understood that in the actual complex specific film manufacturing process, especially the stacking of multiple repeated film layers, the process of the specific material remains unchanged, and finally a specific topography is formed between the multiple repeated film layers. It can be seen that the thickness of each measurement point on the film layer is not independent, but is related to the topography formed between the repeated film layers. Therefore, the measurement points on the film layer should be considered as a whole, and the correlation between the film layers should be considered.

[0074] In this embodiment, for each to-be-measured film layer, the initial film thickness of each first measurement point of the to-be-measured film layer is corrected according to the corresponding target topography constraint library to obtain the corrected film thickness of each first measurement point of the to-be-measured film layer, so as to add topography constraints to the to-be-measured film layer and obtain the corrected film thickness of the to-be-measured film layer.

[0075] And by constructing a simulation model of the to-be-measured film layer according to the corrected film thickness and the characteristics of the thin film, all measurement points of the to-be-measured film layer are considered as a whole, and the film thickness of each measurement point is considered, so as to realize the construction of a more accurate model. Then, according to the simulation data of the simulation model and the theoretical data of the to-be-measured film layer, the real film thickness of the to-be-measured film layer is determined, so as to obtain the accurate film thickness of the to-be-measured film layer.

[0076] Figure 2 is a second flowchart of the method for measuring the film thickness of the thin film provided by an embodiment of the present application.

[0077] As shown in Figure 2 , before step S11, it further includes:

[0078] S21: For each to-be-measured film layer, according to the measured film thickness of each second measurement point of the corresponding preselected film layer and the corresponding reference film thickness, the relative ratio of the film thickness of each second measurement point is determined.

[0079] Wherein, the preselected film layer is a standard thin film sample including one film layer.

[0080] In application, the film thickness of the to-be-measured film layer is unknown, while the corresponding preselected film layer is known. The relative ratio of the film thickness can be determined by the preselected film layer, so as to calculate or correct the film thickness of the to-be-measured film layer in the subsequent process. However, the measured film thickness of the preselected film layer may not be accurate, because there is a certain correlation between the measured film thickness and the reference film thickness of the preselected film layer. Therefore, the measured film thickness of the preselected film layer can be corrected by comparing the measured film thickness with the reference film thickness, so as to obtain the accurate measured film thickness.

[0081] In one possible implementation manner, step S21 includes:

[0082] S211: input the thermal map of the preselected film layer into the generator of the GAN neural network to generate a plurality of to-be-judged thermal maps.

[0083] The GAN neural network is a generative adversarial neural network.

[0084] In application, the generator generates a plurality of fake heat maps, i.e. to-be-discriminated heat maps. Specifically, the generator generates the to-be-discriminated heat maps through rotation and mathematical transformation. The heat map represents the film thickness distribution of the film layer.

[0085] S212: inputting the to-be-discriminated heat map and the real heat map of the film into the discriminator of the GAN neural network to obtain a target heat map output by the discriminator, the target heat map being a to-be-discriminated heat map with a correlation degree greater than a preset correlation degree with the real heat map.

[0086] The real heat map of the film is obtained through accurate measurement technology and can be used as a standard for measuring the film thickness of the preselected film layer. Generally, one real heat map corresponds to one machine.

[0087] In application, the discriminator compares the to-be-discriminated heat map with the real heat map of the film. When the function of the GAN neural network is the minimum, i.e. the correlation degree between the to-be-discriminated heat map and the real heat map of the film is greater than the preset correlation degree, the to-be-discriminated heat map at this time is the film thickness of the preselected film layer after correction, which is the target heat map.

[0088] S213: determining the measured film thickness of each second measurement point of the preselected film layer according to the target heat map.

[0089] The second measurement point can be the same as or different from the first measurement point.

[0090] S214: determining the film thickness relative ratio of each second measurement point according to the measured film thickness and the corresponding reference film thickness of each second measurement point.

[0091] The reference film thickness is the film thickness of the second measurement point of the real heat map.

[0092] It can be understood that the GAN neural network is used for learning and prediction, and the global optimal solution is solved through continuous gradient solving to obtain the optimal heat map of the preselected film layer. The prediction of the GAN neural network does not require a training process such as parameter adjustment, can output results in real time, and the results are stable and have high precision, which is better than the effect of random generation and selection in the prior art.

[0093] In one possible implementation, step S21 includes:

[0094] S211': randomly generating a plurality of to-be-screened heat maps according to the real heat map of the film.

[0095] The real heat map of the film is obtained through accurate measurement technology.

[0096] In the application, according to the randomly generated rotation angle, a plurality of to-be-screened heat maps are generated based on the real heat map.

[0097] S212`:In the plurality of to-be-screened heat maps, a target heat map is screened, and the target heat map is a to-be-screened heat map with a correlation greater than a preset correlation with the real heat map.

[0098] In the application, in the randomly generated to-be-screened heat map, the to-be-screened heat map with a correlation greater than a preset correlation with the real heat map is selected, and at this time, the to-be-screened heat map is the film thickness of the preselected film layer after correction, which is the target heat map.

[0099] S213`:According to the target heat map, the measured film thickness of each second measurement point of the preselected film layer is determined.

[0100] S214`:According to the measured film thickness of each second measurement point and the corresponding reference film thickness, the film thickness relative ratio of each second measurement point is determined, and the reference film thickness is the film thickness of the second measurement point of the real heat map.

[0101] S22: According to the position of each second measurement point and the corresponding film thickness relative ratio, a target topography constraint library of the to-be-measured film layer is generated.

[0102] It can be understood that in the plurality of to-be-screened heat maps, the target heat map is screened, and the heat map of the preselected film layer closest to the real heat map can be screened, which is better than the effect of the prior art of random generation and selection.

[0103] Figure 3 is a third flowchart of the method for measuring the film thickness of the thin film provided by an embodiment of the present application.

[0104] As shown in Figure 3 , step S22 includes:

[0105] S221: According to the position of each second measurement point and the corresponding film thickness relative ratio, an initial topography constraint library of the to-be-measured film layer is generated.

[0106] S222: The rotation angle of the preselected film layer is obtained.

[0107] In the application, the preselected film layer generally has a certain rotation angle, and the rotation angle needs to be used to update the initial topography constraint library.

[0108] S223: According to the rotation angle, the initial topography constraint library is updated to obtain an updated topography constraint library.

[0109] S224: According to the film thickness relative ratio of each second measurement point of the updated topography constraint library, the updated topography constraint library is interpolated to obtain a target topography constraint library.

[0110] In applications, the number of second measurement points is generally small, and therefore interpolation is needed to obtain the film thickness of all points of the preselected film layer.

[0111] In one possible implementation, the updated topography constraint library is interpolated by using the Kriging interpolation method.

[0112] The embodiment of the present application obtains the rotation angle of the preselected film layer, updates the initial topography constraint library according to the rotation angle, and obtains the updated topography constraint library to obtain a more accurate topography constraint library.

[0113] The embodiment of the present application obtains the rotation angle of the preselected film layer, updates the initial topography constraint library according to the rotation angle, and obtains the updated topography constraint library to obtain a more accurate topography constraint library.

[0114] In one embodiment of the present application, step S12 comprises:

[0115] S121: For each first measurement point of each film layer to be measured, the target film thickness relative ratio is determined in the target topography constraint library according to the position of the first measurement point of the film layer to be measured.

[0116] In applications, the corresponding target film thickness relative ratio is obtained from the target topography constraint library according to the position of the first measurement point.

[0117] S122: The initial film thickness is corrected according to the target film thickness relative ratio.

[0118] In one embodiment of the present application, step S13 comprises:

[0119] The simulation model is constructed according to the corrected film thickness of the film layer to be measured, the optical constants of each film layer to be measured, the estimated thickness, and the film layer stacking order of the thin film.

[0120] The characteristics of the thin film include the film layer stacking order and the optical constants and the estimated thickness of each film layer to be measured.

[0121] In applications, attention should be paid to the film layer stacking order and the optical constants and the estimated thickness of each film layer to be measured when constructing the model, and therefore the simulation model of the film layer to be measured should be constructed based on the above factors.

[0122] The optical constants include the refractive index and the dielectric constant. The estimated thickness of each film layer to be measured is the thickness obtained by converting the spectrum measured by the instrument.

[0123] It should be understood that the sequence numbers of the steps in the above embodiments do not mean the execution sequence, and the execution sequence of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0124] Corresponding to the method described in the above embodiment, only the part related to the embodiment of the present application is shown for the convenience of illustration.

[0125] Figure 4 is a structural schematic diagram of a device for measuring film thickness provided by an embodiment of the present application. As shown in Figure 4 , the device comprises:

[0126] The film thickness acquisition module 10 is configured to acquire initial film thicknesses of each to-be-measured film layer of the thin film.

[0127] The corrected film thickness module 11 is configured to correct, for each to-be-measured film layer, the initial film thickness of each first measurement point of the to-be-measured film layer according to a corresponding target topography constraint library to obtain a corrected film thickness of each first measurement point of the to-be-measured film layer, wherein the topography constraint library represents a topographic feature of the film layer.

[0128] The model construction module 12 is configured to construct a simulation model of the to-be-measured film layer according to the corrected film thickness and a feature of the thin film.

[0129] The film thickness determination module 13 is configured to determine a real film thickness of the to-be-measured film layer according to simulation data of the simulation model and theoretical data of the to-be-measured film layer.

[0130] In an embodiment of the present application, further comprising:

[0131] The determination module is configured to determine, for each to-be-measured film layer, a film thickness relative ratio of each second measurement point according to a measured film thickness of the second measurement point of a preselected film layer and a corresponding reference film thickness, wherein the preselected film layer is a standard thin film sample including one film layer.

[0132] The generation module is configured to generate a target topography constraint library of the to-be-measured film layer according to a position of each second measurement point and the film thickness relative ratio.

[0133] In an embodiment of the present application, the determination module is specifically configured to input a thermal map of the preselected film layer into a generator of a GAN neural network to generate a plurality of to-be-discriminated thermal maps; input the to-be-discriminated thermal maps and a real thermal map of the thin film into a discriminator of the GAN neural network to obtain a target thermal map output by the discriminator, wherein the target thermal map is a to-be-discriminated thermal map having a correlation degree greater than a preset correlation degree with the real thermal map; determine the measured film thickness of each second measurement point of the preselected film layer according to the target thermal map; and determine the film thickness relative ratio of each second measurement point according to the measured film thickness of each second measurement point and a corresponding reference film thickness, wherein the reference film thickness is a film thickness of the second measurement point of the real thermal map.

[0134] In an embodiment of the present application, the determining module is specifically configured to randomly generate a plurality of to-be-screened thermal maps according to the real thermal map of the thin film; screen a target thermal map from the plurality of to-be-screened thermal maps, the target thermal map being a to-be-screened thermal map having a correlation with the real thermal map greater than a preset correlation degree; and determine the measured film thickness of each second measurement point of the preselected film layer according to the target thermal map, and determine the film thickness relative ratio of each second measurement point according to the measured film thickness and the corresponding reference film thickness of each second measurement point, the reference film thickness being the film thickness of the second measurement point of the real thermal map.

[0135] In an embodiment of the present application, the generating module is specifically configured to generate an initial topography constraint library of the to-be-measured film layer according to the positions of the second measurement points and the film thickness relative ratios; obtain the rotation angle of the preselected film layer; update the initial topography constraint library according to the rotation angle to obtain an updated topography constraint library; and perform interpolation on the updated topography constraint library according to the film thickness relative ratios of the second measurement points of the updated topography constraint library to obtain a target topography constraint library.

[0136] In an embodiment of the present application, the correcting film thickness module is specifically configured to, for each first measurement point of each to-be-measured film layer, determine a target film thickness relative ratio in the target topography constraint library according to the position of the first measurement point of the to-be-measured film layer, and correct the initial film thickness according to the target film thickness relative ratio.

[0137] In an embodiment of the present application, the constructing model module is specifically configured to construct a simulation model according to the corrected film thickness of the to-be-measured film layer, the optical constants of each to-be-measured film layer of the thin film, the estimated thickness, and the film layer stacking order of the thin film, the features of the thin film including the film layer stacking order and the optical constants and the estimated thickness of each to-be-measured film layer.

[0138] Figure 5 A structural schematic diagram of an electronic device according to an embodiment of the present application is provided. As shown in the figure, the electronic device 2 of this embodiment includes at least one processor 20 (only one processor is shown in the figure), a memory 21, and a computer program 22 stored in the memory 21 and executable on the at least one processor 20, and the processor 20 implements the steps in any of the method embodiments described above when executing the computer program 22. Figure 5 Figure 5 The electronic device 2 can be a desktop computer, a notebook computer, a palm computer, a cloud server, and the like. The electronic device 2 can include, but is not limited to, the processor 20 and the memory 21. Those skilled in the art can understand that the electronic device 2 shown in the figure is only an example and does not constitute a limitation on the electronic device 2, which can include more or fewer components than those shown in the figure, or combine certain components, or different components, for example, can also include input / output devices, network access devices, and the like.

[0139] The electronic device 2 can be a desktop computer, a notebook computer, a palm computer, a cloud server, and the like. The electronic device 2 can include, but is not limited to, the processor 20 and the memory 21. Those skilled in the art can understand that the electronic device 2 shown in the figure is only an example and does not constitute a limitation on the electronic device 2, which can include more or fewer components than those shown in the figure, or combine certain components, or different components, for example, can also include input / output devices, network access devices, and the like. Figure 5 ​​

[0140] The processor 20 can be a central processing unit (CPU), and can also be other general-purpose processors, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0141] The memory 21 can be an internal storage unit of the electronic device 2 in some embodiments, for example, a hard disk or a memory of the electronic device 2. The memory 21 can also be an external storage device of the electronic device 2 in other embodiments, for example, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. Further, the memory 21 can include both the internal storage unit and the external storage device of the electronic device 2. The memory 21 is used to store an operating system, an application program, a boot loader, data and other programs, for example, program codes of the computer program, etc. The memory 21 can also be used to temporarily store data that has been output or is to be output.

[0142] It should be noted that the information interaction, execution process, etc. between the above apparatuses / units, since based on the same concept as the method embodiments of the present application, the specific functions and the brought technical effects can be referred to the method embodiments part, and will not be described here in detail.

[0143] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is exemplified, and in actual application, the above-mentioned functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or software functional unit. In addition, the specific name of each functional unit and module is only for easy distinction, and does not limit the protection scope of the application. The specific working process of the unit and module in the above system can refer to the corresponding process in the foregoing method embodiment, which will not be described here.

[0144] The embodiment of the application further provides a computer readable storage medium, the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the steps in each of the method embodiments.

[0145] The embodiment of the application provides a computer program product, when the computer program product runs on an electronic device, so that the electronic device executes the steps in each of the method embodiments.

[0146] The integrated unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on this understanding, the application can implement all or part of the processes in the above-mentioned embodiment methods by a computer program to instruct related hardware to complete, and the computer program can be stored in a computer readable storage medium. The computer program, when executed by a processor, can implement the steps in each of the method embodiments. The computer program includes computer program code, which can be in the form of source code, object code, executable files or some intermediate forms, etc. The computer readable medium at least includes any entity or device capable of carrying the computer program code to the photographing device / terminal equipment, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium. For example, U disk, mobile hard disk, magnetic disk or optical disk, etc. In some jurisdictions, according to legislation and patent practice, the computer readable medium cannot be an electrical carrier signal and a telecommunication signal.

[0147] In the above embodiments, the description of each embodiment focuses on different aspects, and the parts not described or recorded in a certain embodiment can be referred to the relevant description of other embodiments.

[0148] Those skilled in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0149] In the embodiments provided in the present application, it should be understood that the disclosed apparatus / network device and method can be implemented in other ways. For example, the apparatus / network device embodiments described above are merely schematic, for example, the division of the modules or units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed units can be indirect coupling or communication connection through some interfaces, devices or units, and can be electrical, mechanical or other forms.

[0150] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiments.

[0151] The above described embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A method for measuring the thickness of a thin film, characterized in that: include: For each film layer to be measured, determining a relative ratio of the film thickness at each second measurement point according to the measured film thickness at each second measurement point of the corresponding preselected film layer and the corresponding reference film thickness, wherein the preselected film layer is a standard thin film sample including one film layer; generating a target morphology constraint library for the film layer to be measured according to the position of each second measurement point and the corresponding relative ratio of the film thickness; Obtaining the initial film thickness of each first measurement point in each film layer to be measured of the thin film; For each of the film layers to be measured, correcting the initial film thickness at each first measurement point of the film layer to be measured according to a corresponding target morphology constraint library to obtain a corrected film thickness at each first measurement point of the film layer to be measured, wherein the morphology constraint library is used to characterize the morphology characteristics of the film layer; constructing a simulation model of the film layer to be measured according to the corrected film thickness and the characteristics of the film; Determining the actual film thickness of the film layer to be measured based on the simulation data of the simulation model and the theoretical data of the film layer to be measured; The step of generating a target morphology constraint library of the film layer to be measured according to the position of each second measurement point and the corresponding relative ratio of the film thickness comprises: generating an initial morphology constraint library for the film layer to be measured according to the position of each second measurement point and the corresponding relative ratio of the film thickness; Obtaining a rotation angle of the preselected film layer; updating the initial shape constraint library according to the rotation angle to obtain an updated shape constraint library; interpolating the updated topography constraint library according to the relative ratio of the film thickness at each second measurement point in the updated topography constraint library to obtain the target topography constraint library; The step of correcting the initial film thickness of each first measurement point of the film layer to be measured according to the corresponding target morphology constraint library includes: For each of the first measurement points of each of the film layers to be measured, determining a target film thickness relative ratio in the target morphology constraint library according to the position of the first measurement point of the film layers to be measured; The initial film thickness is corrected according to the target film thickness relative ratio.

2. The method according to claim 1, characterized in that Determining the relative ratio of the film thickness at each second measurement point according to the measured film thickness at each second measurement point of the corresponding preselected film layer and the corresponding reference film thickness includes: Inputting the thermal map of the preselected film layer into a generator of a GAN neural network to generate a plurality of thermal maps to be judged; Inputting the to-be-discriminated thermogram and the true thermogram of the film into a discriminator of a GAN neural network to obtain a target thermogram output by the discriminator, wherein the target thermogram is the to-be-discriminated thermogram having a correlation with the true thermogram greater than a preset correlation; determining the measured film thickness of each second measurement point of the preselected film layer according to the target thermal map; The relative ratio of the film thickness at each second measurement point is determined based on the measured film thickness at each second measurement point and the corresponding reference film thickness, where the reference film thickness is the film thickness at the second measurement point of the real thermodynamic map.

3. The method according to claim 1, characterized in that Determining the relative ratio of the film thickness at each second measurement point according to the measured film thickness at each second measurement point of the corresponding preselected film layer and the corresponding reference film thickness includes: randomly generating a plurality of thermograms to be screened according to the actual thermogram of the film; Screening a target thermogram from among the multiple thermograms to be screened, wherein the target thermogram is the thermogram to be screened whose correlation with the real thermogram is greater than a preset correlation; determining the measured film thickness of each second measurement point of the preselected film layer according to the target thermal map; The relative ratio of the film thickness at each second measurement point is determined based on the measured film thickness at each second measurement point and the corresponding reference film thickness, where the reference film thickness is the film thickness at the second measurement point of the real thermodynamic map.

4. The method according to any one of claims 1 to 3, characterized in that The step of constructing a simulation model of the film layer to be measured based on the corrected film thickness and the characteristics of the film comprises: The simulation model is constructed based on the corrected film thickness of the film layer to be measured, the optical constants and estimated thickness of each film layer to be measured and the film layer stacking order of the film. The characteristics of the film include the film layer stacking order and the optical constants and estimated thickness of each film layer to be measured.

5. A device for measuring the thickness of a thin film, characterized in that: include: a determination module for determining, for each film layer to be measured, a relative ratio of the film thickness at each second measurement point of a corresponding preselected film layer based on the measured film thickness at each second measurement point and the corresponding reference film thickness, wherein the preselected film layer is a standard film sample including one film layer; A generation module, for generating a target morphology constraint library of the film layer to be measured according to the position of each second measurement point and the relative ratio of the film thickness; A film thickness acquisition module is used to obtain the initial film thickness of each film layer to be measured; a film thickness correction module, configured to correct, for each of the film layers to be measured, the initial film thickness at each first measurement point of the film layer to be measured according to a corresponding target morphology constraint library, so as to obtain a corrected film thickness at each first measurement point of the film layer to be measured, wherein the morphology constraint library represents the morphology characteristics of the film layer; A model building module is used to build a simulation model of the film layer to be measured according to the corrected film thickness and the characteristics of the film; a film thickness determination module, configured to determine the actual film thickness of the film layer to be measured based on the simulation data of the simulation model and the theoretical data of the film layer to be measured; The generation module is specifically configured to generate an initial morphology constraint library for the film layer to be measured based on the position of each second measurement point and the relative ratio of the film thickness; obtain the rotation angle of the preselected film layer; update the initial morphology constraint library based on the rotation angle to obtain an updated morphology constraint library; interpolate the updated morphology constraint library based on the relative ratio of the film thickness of each second measurement point in the updated morphology constraint library to obtain a target morphology constraint library; The film thickness correction module is specifically used to determine the target film thickness relative ratio according to the position of the first measurement point of each film layer to be measured in the target morphology constraint library for each first measurement point of each film layer to be measured; and correct the initial film thickness according to the target film thickness relative ratio.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method according to any one of claims 1 to 4 is implemented.

7. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 4 is implemented.

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