Film thickness detection method, system, device and storage medium

Abstract

The present application discloses a film thickness detection method, system, device, and storage medium, relating to the field of film measurement technology, including: measuring the tilt angle of the film to be measured and obtaining a spectral interference signal of the film to be measured; analyzing the thickness of the film to be measured based on the spectral interference signal to obtain the error thickness of the film to be measured; and correcting the error thickness according to the tilt angle to obtain the actual thickness of the film to be measured. By introducing a tilt angle compensation mechanism into the traditional film thickness measurement process, the present application avoids the problem of measurement inaccuracy caused by the non-horizontal film surface or equipment vibration, thereby directly eliminating the influence of the incident angle change caused by tilt on the optical path difference, ensuring the true restoration of the actual thickness value, and thus guaranteeing the strict requirements for film thickness detection in actual production.

Description

Technical Field

[0001] The present application relates to the field of thin film measurement technology, and in particular to a thin film thickness detection method, system, device and storage medium. Background Art

[0002] With the rapid development of display technology, OLEDs (Organic Light-Emitting Diodes) have gained a significant position in the high-end display market due to their advantages such as self-luminescence, high contrast, and wide viewing angle. In the OLED manufacturing process, thin-film encapsulation is a critical step in ensuring device stability and extending lifespan. The thickness of the encapsulation film directly affects the OLED's luminous efficiency, color uniformity, and protective performance, making online measurement of the film thickness particularly critical.

[0003] However, in actual production, it is often difficult to achieve a perfectly horizontal position for the substrate on which the encapsulation film is placed; there may be a slight tilt, and the equipment itself may also be affected by vibration, causing a certain degree of slight tilt. Currently commonly used thickness detection methods, such as optical interferometry and ellipsometry, are based on the interaction between light and the film. Substrate tilt changes the angle of incidence of light on the film surface, thereby affecting light reflection, transmission, and interference fringes, ultimately leading to deviations in thickness calculations. In high-precision OLED production, these measurement errors cannot be ignored. They not only affect the performance of individual devices, but can also cause consistency issues between batches, thereby affecting the overall quality and market competitiveness of the product.

[0004] Therefore, how to reduce the measurement error caused by film tilt during film thickness measurement is a problem that needs to be solved urgently. Summary of the Invention

[0005] The main purpose of this application is to provide a film thickness detection method, system, device and storage medium, aiming to solve the technical problem of how to reduce the measurement error caused by film tilt during film thickness measurement.

[0006] To achieve the above objectives, the present application proposes a film thickness detection method, which includes:

[0007] Measuring the tilt angle of the film to be measured and obtaining a spectral interference signal of the film to be measured;

[0008] Analyzing the thickness of the film to be measured based on the spectral interference signal to obtain an error thickness of the film to be measured;

[0009] The error thickness is corrected according to the tilt angle to obtain the actual thickness of the film to be measured.

[0010] In one embodiment, the spectral interference signal includes regional spectral interference signals of each region of the film to be measured, wherein each regional spectral interference signal is obtained by relative motion of the film to be measured relative to the spectrometer, and the step of analyzing the thickness of the film to be measured based on the spectral interference signal to obtain the error thickness of the film to be measured includes:

[0011] Analyzing the regional thickness of the corresponding region of the film to be measured based on any regional spectral interference signal to obtain the regional error thickness of the film to be measured in the corresponding region;

[0012] The error thickness of the film to be measured is determined according to the error thickness of each area.

[0013] In one embodiment, the tilt angle includes the regional tilt angle of each region of the film to be measured, the error thickness includes the regional error thickness of each region of the film to be measured, and the step of correcting the error thickness according to the tilt angle to obtain the actual thickness of the film to be measured includes:

[0014] For any target area in the film to be tested, determining the target area tilt angle and target area error thickness corresponding to the target area among the tilt angles of each area and the error thickness of each area;

[0015] Correcting the target area thickness error according to the target area inclination angle to obtain the actual thickness of the target area;

[0016] After traversing each target area, the actual thickness of the film to be measured is determined based on the actual thickness of each area.

[0017] In one embodiment, the target area tilt angle includes the sub-area tilt angle of each sub-area in the target area, the target area error thickness includes the sub-area error thickness of each sub-area in the target area, and the step of correcting the target area error thickness according to the target area tilt angle to obtain the actual thickness of the target area includes:

[0018] For any target sub-region in the film to be tested, determining the target sub-region tilt angle and the target sub-region error thickness corresponding to the target sub-region among the tilt angles of each sub-region and the error thickness of each sub-region;

[0019] Correcting the target subregion thickness error according to the target subregion tilt angle to obtain the target subregion actual thickness;

[0020] After traversing each target sub-region, the actual thickness of the target region is determined based on the actual thickness of each sub-region.

[0021] In one embodiment, the target sub-region tilt angle includes a horizontal axis tilt angle and a vertical axis tilt angle, and the step of correcting the target sub-region error thickness according to the target sub-region tilt angle to obtain the actual sub-region thickness of the target sub-region includes:

[0022] determining a thickness correction parameter based on a product of a cosine value of the horizontal axis inclination angle and a cosine value of the vertical axis inclination angle;

[0023] The actual thickness of the sub-region of the target sub-region is determined according to the product of the thickness correction parameter and the error thickness of the target sub-region.

[0024] In one embodiment, the step of measuring the tilt angle of the film to be measured includes:

[0025] Controlling a reference plate of a preset tilt detection device to perform phase shift to obtain a tilt detection interference signal of the film to be measured, wherein the tilt detection interference signal is generated by light reflected from a first surface of the film to be measured and light reflected from a second surface of the preset reference plane;

[0026] Phase unwrapping processing is performed on the tilt detection interference signal to obtain the tilt angle of the film to be measured.

[0027] In one embodiment, the step of obtaining the spectral interference signal of the thin film to be measured includes:

[0028] Invoking a preset broad-spectrum light source to illuminate the film to be tested, so that the film to be tested generates an interference signal to be received;

[0029] The interference signal to be received that is focused by a preset telecentric objective lens is received by a spectrometer to obtain a spectral interference signal of the film to be measured.

[0030] In addition, to achieve the above-mentioned purpose, the present application also proposes a film thickness detection system, which includes:

[0031] A detection module, used to measure the tilt angle of the film to be tested and obtain a spectral interference signal of the film to be tested;

[0032] An analysis module, configured to analyze the thickness of the film to be measured based on the spectral interference signal to obtain an error thickness of the film to be measured;

[0033] The correction module is used to correct the error thickness according to the tilt angle to obtain the actual thickness of the film to be measured.

[0034] In addition, to achieve the above-mentioned purpose, the present application also proposes an electronic device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the film thickness detection method as described above.

[0035] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium. A computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the film thickness detection method described above are implemented.

[0036] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps of the film thickness detection method as described above are implemented.

[0037] One or more technical solutions proposed in this application have at least the following technical effects:

[0038] This application first measures the tilt angle of the film to be measured and obtains the spectral interference signal of the film to be measured, so as to provide key input parameters for subsequent thickness error correction by simultaneously obtaining the geometric tilt state and optical response characteristics of the film, and ensure that the measurement system can perceive and quantify the actual impact of the substrate tilt on the optical path; then the thickness of the film to be measured is analyzed based on the spectral interference signal to obtain the error thickness of the film to be measured, so as to obtain the preliminary thickness distribution of the film from the spectral signal, but there is a systematic error due to the influence of the tilt, which provides baseline data for subsequent correction; finally, the error thickness is corrected according to the tilt angle to obtain the actual thickness of the film to be measured, so as to introduce the tilt angle into the correction calculation through the geometric optical model to calibrate the error thickness, eliminate the optical path deviation caused by the substrate tilt, and convert the error thickness into the true thickness perpendicular to the film surface, which significantly improves the thickness measurement accuracy and ensures high consistency production requirements.

[0039] In summary, the present application avoids the problem in the traditional method that the incident angle of light deviates from the preset vertical direction due to the tilt of the substrate, resulting in the offset of the reflected / transmitted light path and the phase distortion of the interference fringes, which ultimately causes a systematic deviation between the calculated thickness value and the actual value by introducing a tilt angle compensation mechanism into the traditional film thickness measurement process. That is, it avoids the problem of measurement inaccuracy caused by the non-horizontal surface of the film or the vibration of the equipment, thereby directly eliminating the influence of the change in the incident angle caused by the tilt on the optical path difference, and especially significantly improves the measurement accuracy of the film thickness under tilted or vibrating conditions, ensuring the true restoration of the actual thickness value, thereby guaranteeing the strict requirements for film thickness detection in actual production. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0041] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0042] Figure 1 A schematic diagram of a process flow for the first embodiment of the thin film thickness detection method of the present application;

[0043] Figure 2 A schematic diagram of a spectral interference signal of a thin film thickness detection method provided in Example 1 of the present application;

[0044] Figure 3 A schematic diagram of a thickness analysis scenario of a thin film thickness detection method provided in Example 1 of the present application;

[0045] Figure 4 A schematic diagram of an inclined scenario of the film thickness detection method provided in Example 1 of the present application;

[0046] Figure 5 A schematic diagram of a flow chart provided for Example 2 of the thin film thickness detection method of this application;

[0047] Figure 6 A schematic diagram of the system architecture of the film thickness detection method provided in Example 2 of the present application;

[0048] Figure 7 A schematic diagram of the structure of a film thickness detection method according to the second embodiment of the present application;

[0049] Figure 8 This is a schematic diagram of the module structure of the film thickness detection system according to an embodiment of the present application;

[0050] Figure 9 Schematic diagram of the device structure of the hardware operating environment involved in the film thickness detection method in the embodiment of the present application.

[0051] Description of the accompanying drawings of the embodiment:

[0052]

[0053] The purpose, features and advantages of this application will be further explained with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0054] It should be understood that the specific embodiments described herein are merely used to explain the technical solutions of the present application and are not intended to limit the present application.

[0055] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0056] The main solution of the embodiment of the present application is: measuring the tilt angle of the film to be measured and obtaining the spectral interference signal of the film to be measured; analyzing the thickness of the film to be measured based on the spectral interference signal to obtain the error thickness of the film to be measured; correcting the error thickness according to the tilt angle to obtain the actual thickness of the film to be measured.

[0057] Because in actual production, it is often difficult to place the substrate of the encapsulation film in a perfectly horizontal state, there may be a slight tilt, and the equipment itself may also be affected by vibration, causing a certain amount of slight tilt. Currently commonly used thickness detection methods such as optical interferometry and ellipsometry are based on the interaction between light and film. The tilt of the substrate will change the incident angle of light on the surface of the film, thereby affecting the reflection, transmission and interference fringes of light, and ultimately leading to deviations in the thickness calculation. In high-precision OLED production, these measurement errors cannot be ignored. Not only will they affect the performance of individual devices, they may also cause consistency problems between batches, thereby affecting the overall quality and market competitiveness of the product. Therefore, how to reduce the measurement error caused by film tilt during the film thickness measurement process is a problem that urgently needs to be solved.

[0058] The present application provides a solution by introducing a tilt angle compensation mechanism in the traditional film thickness measurement process, thereby avoiding the traditional method in which the light incident angle deviates from the preset vertical direction due to the tilt of the substrate, resulting in the offset of the reflected / transmitted light path and the phase distortion of the interference fringes, which ultimately causes a systematic deviation between the calculated thickness value and the actual value. That is, it avoids the problem of measurement inaccuracy caused by the non-horizontal film surface or equipment vibration, thereby directly eliminating the influence of the incident angle change caused by tilt on the optical path difference, and especially significantly improves the measurement accuracy of the film thickness under tilted or vibrating conditions, ensuring the true restoration of the actual thickness value, thereby guaranteeing the strict requirements for film thickness detection in actual production.

[0059] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, mobile phone, etc., or an electronic device capable of implementing the above functions, a film thickness detection system, etc. The following uses the film thickness detection system as an example to illustrate this embodiment and the following embodiments.

[0060] Based on this, the present invention provides a method for detecting the thickness of a thin film. Figure 1 , Figure 1 This is a flow chart of the first embodiment of the film thickness detection method of the present application.

[0061] In this embodiment, the film thickness detection method includes steps S10 to S30:

[0062] Step S10, measuring the tilt angle of the film to be measured, and obtaining a spectral interference signal of the film to be measured;

[0063] It should be noted that the tilt angle refers to the spatial deviation angle of the film surface relative to the ideal horizontal plane, which is caused by the offset of the film substrate placement or the vibration of the equipment; the spectral interference signal refers to the interference phenomenon caused by the reflection or transmission of light on the upper and lower surfaces of the film, and its spectral characteristics (such as fringe frequency and phase) are related to the film thickness.

[0064] It is understandable that in traditional film thickness detection, substrate placement offset or equipment vibration can cause the film surface to tilt, causing the incident light to deviate from the vertical direction. The traditional method ignores the tilt angle, resulting in systematic errors in subsequent thickness analysis. Therefore, performing step S10 can avoid the incident light path offset caused by ignoring the tilt angle, causing optical path difference calculation errors and interference signal distortion, and thus causing thickness measurement deviation. By measuring the tilt angle in real time and synchronously collecting spectral data, reliable geometric and optical parameter inputs are provided for subsequent corrections.

[0065] Illustratively, a laser interferometer is used to project reference light onto the film surface, the tilt angle of the film surface is calculated by phase difference analysis, a broadband light source (such as a halogen lamp) is simultaneously used to illuminate the film, the reflected light is collected by a telecentric objective lens, and the spectral interference signal (wavelength-light intensity distribution) is recorded by an imaging spectrometer.

[0066] Step S20, analyzing the thickness of the film to be measured based on the spectral interference signal to obtain an error thickness of the film to be measured;

[0067] It should be noted that the error thickness refers to the thickness value analyzed based on the ideal vertical incidence assumption when the tilt angle correction is not considered, which includes the optical path difference error caused by tilt.

[0068] It is understandable that since traditional thickness analysis directly assumes that light is incident vertically and does not consider the change in incident angle caused by tilt, the optical path difference deviates from the true value and the calculated result contains errors. Therefore, step S20 is performed to determine the preliminary thickness distribution of the film based only on the spectral interference signal, retaining the error characteristics introduced by the tilt, and providing benchmark data for subsequent corrections.

[0069] For example, please refer to Figure 2 , Figure 2 Schematic diagram of spectral interference signal in the 400nm~600nm band. Figure 3 , the interference image distribution obtained from the spectral interference signal is:

[0070]

[0071] in, The upper surface of the film to be tested The reflected light intensity value, The lower surface of the film to be tested The reflected light intensity value, n is the refractive index of the film to be measured, d is the error thickness of the film to be measured, is the wavelength of the incident light. Among them, the phase difference of the reflected light for:

[0072]

[0073] when is 2 When the spectral interference signal is an integer multiple of and The relationship between θ and phase difference is:

[0074]

[0075] make , then the error thickness of the film can be expressed as:

[0076]

[0077] To solve T, the spectral interference signal can be converted to the wavenumber domain and solved by using the Lomb-Scargle periodogram, or it can be solved by Fourier transform to the spectrum domain.

[0078] In a feasible embodiment, the spectral interference signal includes regional spectral interference signals of each region of the film to be measured, wherein each regional spectral interference signal is obtained by the relative movement of the film to be measured relative to the spectrometer. Step S20 may include steps S21-S22:

[0079] Step S21, analyzing the regional thickness of the corresponding region of the film to be measured based on any regional spectral interference signal to obtain the regional error thickness of the film to be measured in the corresponding region;

[0080] It should be noted that the regional spectral interference signal refers to the reflection / transmission spectral interference signal collected separately for each independent area when the film to be tested is divided into multiple independent areas, which contains the interference fringe information caused by thickness and tilt angle in the area; the regional error thickness refers to the thickness value of a single area that is not corrected for the tilt effect and is analyzed based on its spectral interference signal (that is, the calculated thickness assuming that the light in the area is incident vertically).

[0081] It is understandable that, because traditional optical film thickness gauges typically consist of a light source, a measuring head, and a detector for transmission or reflection measurement, they can only monitor a single measurement point and cannot measure the film thickness of the entire package area. Although multiple identical film thickness measurement systems can be deployed to simultaneously measure multiple measurement points, this is costly and relatively inefficient. Differences between different devices can also introduce errors into the measurement results. Alternatively, using a global spectral signal to analyze thickness can mask local errors due to differences in light incident angles or optical path length differences across different regions, averaging them together and failing to accurately reflect the true deviations in each region. Therefore, step S21 is performed to achieve full coverage of the film thickness measurement by segmenting using a line scan. This avoids the high cost, low efficiency, and large errors associated with deploying multiple identical film thickness measurement systems, as well as the distortion of localized thickness errors caused by mixed calculations of tilt angles or thickness differences across different regions (for example, differences in incident angles between the center and edge regions are ignored). Thus, through segmented analysis, the independent optical characteristics and thickness deviations of each region are accurately captured, preventing local errors from being diluted by global data and providing a high-quality error distribution foundation for subsequent overall correction.

[0082] Exemplarily, the film to be tested is divided into several rectangular grid areas, and the film to be tested is controlled to perform relative displacement movement relative to the system, so that the spectrometer collects the reflected spectral interference signal area by area, and performs FFT on the spectral interference signal of each area, that is, the regional spectral interference signal, to calculate the error thickness of each area and generate an error thickness distribution matrix.

[0083] Step S22: determining the error thickness of the film to be measured according to the error thickness of each region.

[0084] For example, through data fusion (such as weighted averaging or spatial interpolation), the scattered regional error thicknesses are integrated into a globally consistent error thickness model, thereby enhancing the ability to characterize the overall heterogeneity of the film and providing a unified benchmark for subsequent tilt correction.

[0085] In this embodiment, the film to be measured is divided into multiple independent areas and spectral interference signals are collected in different areas. Spectral analysis is performed on each area separately, and the regional error thickness is calculated. The error thickness is then generated through data fusion. This avoids the high cost, low efficiency and large error problems caused by the deployment of multiple identical film thickness measurement systems, as well as the problem of insufficient spatial resolution caused by the averaging effect of traditional global signal analysis that masks local tilt or uneven thickness. High-precision local error capture is achieved, which is particularly suitable for nanometer-level thickness uniformity detection of large-size flexible films or OLED panels.

[0086] Step S30 , correcting the thickness error according to the tilt angle to obtain the actual thickness of the film to be measured.

[0087] It should be noted that the actual thickness refers to the true thickness value perpendicular to the film surface after correction of the tilt angle.

[0088] It is understandable that since the error thickness is based on the assumption of vertical incidence, but the actual incident angle changes due to tilt, geometric correction is required to eliminate the influence of tilt on the optical path difference. Therefore, step S30 is performed to overcome the optical path difference amplification effect caused by tilt in the error thickness (such as the optical path difference is mistakenly divided by cosθ, the cosine value of the tilt angle), avoid the problem of the true thickness value being overestimated or underestimated, and thus restore the error thickness to the true thickness through geometric compensation, significantly improving the measurement accuracy of the film thickness.

[0089] For example, please refer to Figure 4 , the tilt angle Substitute into the correction formula to calculate the actual thickness : The thickness distribution of the entire film is corrected by spatial interpolation, thereby generating a high-precision three-dimensional thickness distribution map that reflects the true thickness of the film.

[0090] In a feasible embodiment, the tilt angle includes the regional tilt angle of each region of the film to be measured, and the error thickness includes the regional error thickness of each region of the film to be measured. Step S30 may include steps S31 to S33:

[0091] Step S31, for any target area in the film to be tested, determining the target area tilt angle and target area error thickness corresponding to the target area among the tilt angles of each area and the error thickness of each area;

[0092] It should be noted that the target area refers to dividing the film to be tested into multiple independent areas, with each area serving as an independent analysis unit; the target area tilt angle refers to the tilt angle of the film surface in the target area relative to the reference plane; the target area error thickness refers to the thickness value without correction for the tilt effect based on the analysis of the spectral interference signal in this area.

[0093] It is understandable that due to the spatial heterogeneity of the tilt angle and thickness non-uniformity of large-scale films, step S31 is performed. By analyzing the local tilt and optical properties of each target area separately, the problem of distortion of the overall error thickness calculation due to ignoring local tilt differences in global analysis can be avoided, thereby accurately capturing the spatial distribution of local tilt and error thickness, and improving measurement resolution and local accuracy.

[0094] Step S32, correcting the target area thickness error according to the target area inclination angle to obtain the actual thickness of the target area;

[0095] It is understandable that since the error thickness is based on the assumption of vertical incidence, the actual angle of incidence changes due to regional tilt, so step S32 is performed to eliminate the influence of tilt on the optical path difference through geometric correction. This avoids the error thickness from being amplified due to the optical path difference not corrected for the tilt angle, resulting in a systematic overestimation or underestimation of the thickness value. The local error thickness is restored to the true thickness, thereby improving the measurement accuracy of a single area.

[0096] In a feasible implementation, the target area tilt angle includes the sub-area tilt angle of each sub-area in the target area, the target area error thickness includes the sub-area error thickness of each sub-area in the target area, and step S32 may include steps S321 to S323:

[0097] Step S321, for any target sub-region in the film to be tested, determining the target sub-region tilt angle and target sub-region error thickness corresponding to the target sub-region among the tilt angles of each sub-region and the error thickness of each sub-region;

[0098] It should be noted that the target sub-area refers to the further division of the film to be tested in a certain area into independent analysis units according to the physical position, and each unit is called a target sub-area; the target sub-area tilt angle refers to the spatial angle between the film surface and the detection reference plane in the target sub-area, which is measured by a laser interferometer or optical sensor; the target sub-area error thickness refers to the thickness value analyzed based on the spectral interference signal of the target sub-area. This data does not take into account the influence of the tilt angle on the optical path.

[0099] It is understandable that due to the spatial heterogeneity of the film surface tilt and thickness errors, such as warping of the edges or center depression of large-sized films, step S321 is performed to further analyze the local morphology of each target sub-region in the region independently to avoid regional averaging from masking smaller local defects, causing the error thickness calculation value to deviate from the true value. By further partitioning the region and independently detecting it, the spatial distribution of local tilt and error thickness can be accurately captured, providing a high-resolution data basis for subsequent corrections.

[0100] Step S322, correcting the target sub-region thickness error according to the target sub-region tilt angle to obtain the target sub-region actual thickness;

[0101] It can be understood that since the error thickness of the target sub-area is based on the assumption of vertical incidence, and the actual incident light factor area is tilted to produce an angular offset, step S322 is performed to eliminate the amplification effect of the tilt on the optical path difference through geometric correction. This can avoid the systematic deviation of the error thickness calculation value due to the amplification of the optical path difference when the tilt angle is not corrected at a smaller granularity, thereby effectively restoring the true thickness at a smaller granularity.

[0102] Step S323 : After traversing each target sub-region, determining the actual thickness of the target region based on the actual thickness of each sub-region.

[0103] It can be understood that since the overall thickness of the film needs to integrate the correction results of all sub-regions, step S323 can be performed to avoid the problem of thickness mutation caused by direct splicing of sub-region data due to measurement noise or interpolation loss, thereby generating a continuous and smooth thickness distribution map through spatial interpolation and filtering algorithms.

[0104] For example, the actual thickness of all sub-regions in a certain area is filtered by 3σ to eliminate abnormal data that deviates from the mean by more than 3 standard deviations. The Kriging interpolation algorithm is then used to generate a global thickness distribution surface based on the thickness values of adjacent sub-regions to obtain the actual thickness of the target area.

[0105] In this embodiment, the area of the film to be measured is further divided into multiple sub-areas, and the tilt angle and the error thickness generated by the analytical spectral interference signal are measured area by area. At the same time, geometric correction is introduced to eliminate the optical path difference amplification error caused by the tilt to obtain the actual thickness of the corresponding area. This avoids the problem of traditional methods that ignore tiny local tilt heterogeneity, and achieves high-precision measurement of a single sub-area. It is particularly suitable for high-precision uniformity detection of large-scale films.

[0106] Step S33: After traversing each target area, the actual thickness of the film to be measured is determined based on the actual thickness of each area.

[0107] It can be understood that since the overall thickness of the film needs to integrate the correction results of each independent area, step S33 can be performed to avoid the problem of global model discontinuity or outlier interference caused by the isolation of local correction data. By fusing the data of each area, a smooth and continuous global thickness distribution map is generated to meet the high uniformity detection requirements.

[0108] For example, the actual thickness of each region is filtered with 3σ to remove outliers, and then the Kriging interpolation algorithm is used to generate a global thickness distribution based on the data of adjacent regions to obtain the actual thickness of the film to be measured. A three-dimensional thickness heat map of the film can be output, and the maximum / minimum thickness deviation sub-regions can be marked.

[0109] In this embodiment, the film to be measured is divided into multiple regions, and the tilt angle and spectral interference signal are collected region by region. A geometric correction factor is introduced for each region to generate a global actual thickness distribution. This avoids the problem of error thickness system offset caused by ignoring local tilt heterogeneity in traditional global measurement, and achieves high-precision correction of single-region thickness.

[0110] This embodiment provides a thin film thickness detection method. By introducing a tilt angle compensation mechanism in the traditional thin film thickness measurement process, it avoids the problem in the traditional method that the light incident angle deviates from the preset vertical direction due to the tilt of the substrate, resulting in the offset of the reflected / transmitted light path and the phase distortion of the interference fringes, which ultimately causes a systematic deviation between the calculated thickness value and the actual value. That is, it avoids the problem of measurement inaccuracy caused by the non-horizontal film surface or equipment vibration, thereby directly eliminating the influence of the incident angle change caused by tilt on the optical path difference, and especially significantly improves the measurement accuracy of the film thickness under tilted or vibrating conditions, ensures the true restoration of the actual thickness value, and thus guarantees the strict requirements for film thickness detection in actual production.

[0111] In a feasible implementation manner, the target sub-region tilt angle includes a horizontal axis tilt angle and a vertical axis tilt angle, and step S322 may include steps S301 and S302:

[0112] Step S301, determining a thickness correction parameter based on the product of the cosine value of the horizontal axis tilt angle and the cosine value of the vertical axis tilt angle;

[0113] It should be noted that the horizontal axis tilt angle refers to the tilt angle of the film surface in the horizontal direction (X axis); the vertical axis tilt angle refers to the tilt angle of the film surface in the vertical direction (Y axis); the thickness correction parameter refers to the geometric correction factor of the comprehensive dual-axis tilt angle, which can be defined as ,in is the horizontal axis inclination angle, It is the inclination angle of the longitudinal axis.

[0114] It is understandable that since only the tilt angle of the film to be measured is used Without constraining the tilt direction, the dual-axis tilt coupling effect is not effectively eliminated, and the optical path difference amplification error may still exist. Therefore, step 301 is performed to uniformly quantify the impact of multi-dimensional tilt on the optical path difference by introducing a correction parameter for the dual-axis cosine product, thereby avoiding the residual error of a single-axis correction.

[0115] Step S302 : determining the actual thickness of the target sub-region according to the product of the thickness correction parameter and the error thickness of the target sub-region.

[0116] For example, the thickness correction parameter The actual thickness of the target sub-region is calculated by multiplying the error thickness d of the target sub-region by : .

[0117] In this embodiment, by measuring the horizontal axis tilt angle and the vertical axis tilt angle of the target sub-area, the dual-axis cosine product is calculated as the thickness correction parameter, and the correction parameter is used to correct the error thickness of the target sub-area. This avoids the thickness calculation error caused by ignoring the dual-axis tilt coupling effect in the traditional single-axis tilt correction method, realizes the full compensation of the geometric error of the dual-axis tilt, and fully meets the high-precision detection requirements of the film for the full-area thickness.

[0118] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above embodiment 1 can be referred to the above introduction and will not be described in detail later. Figure 5 The step of measuring the tilt angle of the film to be measured in step S10 may further include steps S11 to S12:

[0119] Step S11, controlling a reference plate of a preset tilt detection device to perform phase shift to obtain a tilt detection interference signal of the film to be measured, wherein the tilt detection interference signal is generated by light reflected from a first surface of the film to be measured and light reflected from a second surface of the preset reference plane;

[0120] It should be noted that the reference plate refers to an optical plate with a certain reflective film and high flatness in the preset tilt detection equipment, and its displacement along the optical axis is controlled by the piezoelectric ceramic driver PZT to produce phase shift; the tilt detection interference signal refers to the fringe signal formed by the interference of the reflected light between the first surface of the film and the second surface of the reference plane, and its phase difference contains the film tilt information.

[0121] It is understandable that since traditional tilt detection relies on single interference fringe analysis, it is unable to distinguish between the tilt direction of the film and phase changes, resulting in angle measurement errors. Therefore, step S11 is performed to eliminate environmental vibration interference through multi-step phase shifting, thereby achieving high-precision dynamic detection of the tilt angle.

[0122] For example, a piezoelectric ceramic is used to drive the reference plane to move four times with a step size of λ / 4 (when λ = 632.8 nm), and the interference fringe image is synchronously collected. The initial phase distribution is calculated using a four-step phase shift algorithm. For example, when the fringe offset Δx = 10 pixels is measured, the tilt angle θ ≈ arcsin(Δxλ / (2D)) ≈ 1.5° is calculated, where D is the pixel pitch of the detector.

[0123] Step S12: performing phase unwrapping processing on the tilt detection interference signal to obtain the tilt angle of the film to be measured.

[0124] It should be noted that phase unwrapping processing refers to eliminating phase jumps and restoring continuous phase distribution through spatial or temporal domain phase unwrapping algorithms (such as the least squares method and the Goldstein algorithm).

[0125] It is understandable that due to the phase jump, the traditional algorithm cannot restore the true phase, and the tilt angle calculation has periodic errors. Therefore, step S12 can avoid the misjudgment of the tilt direction caused by the phase jump, thereby realizing the continuous mapping of the tilt angle of the entire film to be tested.

[0126] Exemplarily, the Flynn least squares unwrapping algorithm is used to perform pixel-by-pixel unwrapping on the obtained wrapped phase matrix, for example, the wrapped phase value is expanded from -π to π to 0 to 4π, combined with the adjacent pixel gradient constraints, to output a continuous phase field and calculate the tilt angle θ of the film to be measured.

[0127] The step of obtaining the spectral interference signal of the thin film to be measured in step S10 may further include steps S13 and S14:

[0128] Step S13, calling a preset broad-spectrum light source to illuminate the film to be tested, so that the film to be tested generates an interference signal to be received;

[0129] It should be noted that the preset wide-spectrum light source refers to a wide-spectrum light source covering visible light to near-infrared (such as a xenon lamp, with a wavelength range of 400-1000 nm), which can eliminate order ambiguity through low-coherence interference.

[0130] It is understandable that since the narrow-band light source (such as He-Ne laser) has a narrow spectral range, the film thickness measurement is limited by the interference order ambiguity. Therefore, step S13 is performed to utilize the wide spectrum low coherence characteristics to achieve unambiguous measurement of the film thickness, avoiding the problem of order confusion.

[0131] For example, a xenon lamp light source (wavelength 400-1000 nm, half-width 200 nm) is used to illuminate the film, and a beam splitter prism is used to separate the reference light and the film reflected light to generate a low-coherence interference signal, such as an interference envelope with a central wavelength λ = 700 nm.

[0132] Step S14: receiving the interference signal to be received that is focused by a preset telecentric objective lens through a spectrometer to obtain a spectral interference signal of the thin film to be measured.

[0133] It should be noted that a preset telecentric objective lens refers to an optical lens with a telecentric optical path design on the object side, where the main light on the image side is parallel to the optical axis, which can eliminate parallax and distortion.

[0134] It is understandable that due to the field distortion and aberration of conventional objective lenses, the spatial resolution of the spectral signal decreases. Therefore, performing step S14 can ensure that the spectral interference signals at different spatial positions strictly correspond to the thin film area, thereby effectively improving the spatial consistency of the film thickness measurement.

[0135] For example, the interference signal to be received generated by the film to be measured is focused and imaged on the incident slit of the imaging spectrometer through a telecentric objective lens, so as to reduce the difficulty of analyzing the reflected light signals at different line scanning width positions.

[0136] In this embodiment, a phase-shifting interference technique is used to control the phase shift of a preset reference plane, and a tilt detection interference signal is generated by the reflected light from the first surface of the film to be measured and the reflected light from the second surface of the preset reference plane. The phase unwrapping processing technique is combined to accurately measure the tilt angle of the film to be measured. At the same time, a wide-spectrum light source is used to illuminate the film to be measured, and the interference signal is converged by a telecentric objective lens system to obtain a spectral interference signal. This effectively avoids the multi-dimensional measurement inaccuracy problem caused by single phase shift, phase jump, narrow-band light source and conventional objective lens aberration in traditional interference methods, and realizes accurate and stable measurement of the tilt angle and thickness of the film simultaneously, thereby improving the accuracy of film thickness control during the film manufacturing process and ensuring device performance and product quality.

[0137] For example, in order to help understand the implementation process of the film thickness detection method obtained by combining this embodiment with the above embodiment 1, please refer to Figure 6 , Figure 6 A schematic diagram of the system architecture of a film thickness detection method is provided, specifically:

[0138] The system includes a tilt detection device 1, a film thickness detection device, and a spectroscopic component 5, wherein the film thickness detection device includes an imaging objective lens 2 and an imaging spectrometer 3. In addition, the dotted line in the figure represents the optical axis, and the solid line and the dotted line both represent the corresponding light rays.

[0139] The tilt detection device 1 is used to detect the tilt angle of the film 6 to be tested, and obtain the tilt angle of the film to be tested relative to the optical axis through analysis and calculation by the computer 4;

[0140] The imaging objective lens 2 is used to image the film 6 to obtain the spectral interference signal of the film. The image plane of the imaging objective lens is located at the incident slit position of the imaging spectrometer 3. The imaging objective lens 2 images the film to be measured with a certain width, which is the scanning width L1. When the film to be measured moves relative to the system, the thickness of the entire film to be measured is detected to obtain the error thickness of the film to be measured.

[0141] The imaging spectrometer 3 is used to receive the light signal focused by the imaging objective lens and extract the spectral interference signal in the spectral dimension. Finally, the computer 4 analyzes and calculates it and compensates for the tilt error of the film sample to obtain the actual thickness of the film to be measured, thereby realizing high-precision measurement of the thickness of the packaging film.

[0142] Further, please refer to Figure 7 , Figure 7 This is a schematic diagram of the structure of a specific embodiment of a thin film thickness detection method. The tilt detection device 1 shown in the figure is composed of a typical Fizeau laser interferometer optical path. Alternatively, a Twyman-Green interferometer optical path or a Mach-Zehnder interferometer optical path can be used as a tilt detection device. The module consists of an illumination unit, a first beam splitter 104, a collimating objective lens 105, a reference plane 106, and an imaging unit. The illumination unit comprises a light source 101, a focusing objective lens 102, and a pinhole 103. A helium-neon laser with a wavelength of 632.8 nm can be used as the light source. The focusing objective lens can be a microscope objective lens, thus forming an illumination system. The first beam splitter 104 is used to receive the interference light signal from the side. The beam splitter can be a semi-transparent, semi-reflective beam splitter prism or a beam splitter plate. The imaging unit consists of an aperture 107, an imaging lens 108, and a detector 109, which is used to receive the generated interference signal. The reference plane 106 is a flat plate coated with a certain reflective film and is controlled by a piezoelectric ceramic PTZ drive. When the film to be tested is placed at a tilt angle θ, the reflected light from the surface of the film to be tested 6 and the reflected light from the reference plane 106 form an interference signal, i.e., a tilt detection interference signal, which is received by the imaging unit. The reference plane 106, driven by piezoelectric ceramics, uses PTZ phase shifting technology to obtain a series of interference signals. Through two-dimensional phase unwrapping, the tilt angle of the film to be tested along the X direction is obtained. and the tilt angle along the Y direction , assuming that the X direction is parallel to the scanning line and the Y direction is the movement direction of the film to be measured.

[0143] Under the action of the illumination objective lens 202, the broadband light source 201 uniformly illuminates the thin film sample to be tested through the telecentric objective lens 204. In particular, the illumination area matches the scanning width L1. The illumination objective lens 202 can be configured as a typical Köhler illumination system. The broadband light source is usually selected as an incandescent lamp, a continuous spectrum LED or a halogen lamp, etc. The spectroscopic component 5 is used to separate the signal light for film thickness detection and the signal light for tilt angle detection. The spectroscopic component can be selected as a dichroic spectrometer. The interference signal generated by the packaged thin film to be tested is converged and imaged at the incident slit of the imaging spectrometer 3 after passing through the telecentric objective lens 204 and the second spectrometer 203, and the imaging spectrometer receives the spectral interference signal. Among them, the telecentric objective lens 204 can reduce the difficulty of analyzing the reflected light signals at different line scan width positions.

[0144] Imaging spectrometer 3 incident slit length corresponding to scan width , and receives spectral interference signals during detection. As an embodiment, the scanning width is 8mm, the imaging lens is a telecentric objective lens 204, the magnification is 2×, the incident slit length of the imaging spectrometer is 16mm, and the imaging spectrometer F number is 2.6, so as to fully receive the signal light focused by the imaging lens. The imaging spectrometer wavelength range is 400nm-600nm, and the spectral resolution is 0.2nm. The spectral range is selected to avoid the wavelength of the laser in the tilt angle detection module, so that the spectrometer component 5 can distinguish the optical signals and avoid mutual interference.

[0145] The imaging spectrometer 3 receives a spectral interference signal with N pixel dimensions, and the slit length corresponds to a dimension of M pixels. Therefore, the imaging spectrometer can obtain M similar spectral interference signals, namely sub-region spectral interference signals. Each signal is analyzed to calculate the film thickness at the corresponding detection point, thereby achieving online thickness measurement of the entire film scanning area.

[0146] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the film thickness detection method of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0147] This application also provides a film thickness detection system, please refer to Figure 8 , the film thickness detection system comprises:

[0148] The detection module 10 is used to measure the tilt angle of the film to be tested and obtain the spectral interference signal of the film to be tested;

[0149] An analysis module 20 is configured to analyze the thickness of the film to be measured based on the spectral interference signal to obtain an error thickness of the film to be measured;

[0150] The correction module 30 is used to correct the error thickness according to the tilt angle to obtain the actual thickness of the film to be measured.

[0151] Optionally, the spectral interference signal includes regional spectral interference signals of each region of the film to be measured, wherein each regional spectral interference signal is obtained by relative motion of the film to be measured relative to the spectrometer, and the analyzing module 20 is further configured to:

[0152] Analyzing the regional thickness of the corresponding region of the film to be measured based on any regional spectral interference signal to obtain the regional error thickness of the film to be measured in the corresponding region;

[0153] The error thickness of the film to be measured is determined according to the error thickness of each area.

[0154] Optionally, the tilt angle includes the regional tilt angle of each region of the film to be measured, the error thickness includes the regional error thickness of each region of the film to be measured, and the correction module 30 is further configured to:

[0155] For any target area in the film to be tested, determining the target area tilt angle and target area error thickness corresponding to the target area among the tilt angles of each area and the error thickness of each area;

[0156] Correcting the target area thickness error according to the target area inclination angle to obtain the actual thickness of the target area;

[0157] After traversing each target area, the actual thickness of the film to be measured is determined based on the actual thickness of each area.

[0158] Optionally, the target area tilt angle includes the sub-area tilt angle of each sub-area in the target area, the target area error thickness includes the sub-area error thickness of each sub-area in the target area, and the correction module 30 is further configured to:

[0159] For any target sub-region in the film to be tested, determining the target sub-region tilt angle and the target sub-region error thickness corresponding to the target sub-region among the tilt angles of each sub-region and the error thickness of each sub-region;

[0160] Correcting the target subregion thickness error according to the target subregion tilt angle to obtain the target subregion actual thickness;

[0161] After traversing each target sub-region, the actual thickness of the target region is determined based on the actual thickness of each sub-region.

[0162] Optionally, the target sub-region tilt angle includes a horizontal axis tilt angle and a vertical axis tilt angle, and the correction module 30 is further configured to:

[0163] determining a thickness correction parameter based on a product of a cosine value of the horizontal axis inclination angle and a cosine value of the vertical axis inclination angle;

[0164] The actual thickness of the sub-region of the target sub-region is determined according to the product of the thickness correction parameter and the error thickness of the target sub-region.

[0165] Optionally, the detection module 10 is further configured to:

[0166] Controlling a reference plate of a preset tilt detection device to perform phase shift to obtain a tilt detection interference signal of the film to be measured, wherein the tilt detection interference signal is generated by light reflected from a first surface of the film to be measured and light reflected from a second surface of the preset reference plane;

[0167] Phase unwrapping processing is performed on the tilt detection interference signal to obtain the tilt angle of the film to be measured.

[0168] Optionally, the detection module 10 is further configured to:

[0169] Invoking a preset broad-spectrum light source to illuminate the film to be tested, so that the film to be tested generates an interference signal to be received;

[0170] The interference signal to be received that is focused by a preset telecentric objective lens is received by a spectrometer to obtain a spectral interference signal of the film to be measured.

[0171] The film thickness detection system provided in this application, employing the film thickness detection method described in the aforementioned embodiments, can address the technical problem of reducing measurement errors caused by film tilt during film thickness measurement. Compared to the prior art, the beneficial effects of the film thickness detection system provided in this application are the same as those of the film thickness detection method described in the aforementioned embodiments. Other technical features of the film thickness detection system are the same as those disclosed in the aforementioned embodiments and are not further elaborated here.

[0172] The present application provides an electronic device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the film thickness detection method in the above-mentioned embodiment one.

[0173] Reference below Figure 9, which shows a schematic diagram of the structure of an electronic device suitable for implementing the embodiments of the present application. The electronic devices in the embodiments of the present application may include, but are not limited to, mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), in-vehicle terminals (such as in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 9 The electronic device shown is merely an example and should not limit the functions and scope of use of the embodiments of the present application.

[0174] like Figure 9 As shown, the electronic device may include a processing system 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes based on programs stored in a read-only memory 1002 or programs loaded from a storage system 1003 into a random access memory 1004. The random access memory 1004 also stores various programs and data required for the operation of the electronic device. The processing system 1001, the read-only memory 1002, and the random access memory 1004 are interconnected via a bus 1005. An input / output interface 1006 is also connected to the bus. Typically, the following systems may be connected to the input / output interface 1006: an input system 1007 including, for example, a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; an output system 1008 including, for example, a liquid crystal display (LCD), speakers, and vibrator; a storage system 1003 including, for example, a magnetic tape or hard disk; and a communication system 1009. The communication system 1009 may allow the electronic device to communicate with other devices wirelessly or wired to exchange data. Although the figures show electronic devices with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have instead.

[0175] In particular, according to the embodiments disclosed in the present application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, the embodiments disclosed in the present application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program comprising program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via a communication system, or installed from a storage system 1003, or installed from a read-only memory 1002. When the computer program is executed by the processing system 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are performed.

[0176] The electronic device provided in this application, utilizing the film thickness detection method described in the aforementioned embodiment, can address the technical problem of reducing measurement errors caused by film tilt during film thickness measurement. Compared to the prior art, the electronic device provided in this application achieves the same beneficial effects as the film thickness detection method described in the aforementioned embodiment. Other technical features of this electronic device are the same as those disclosed in the aforementioned embodiment and are not further elaborated here.

[0177] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0178] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

[0179] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, a computer program) stored thereon, wherein the computer-readable program instructions are used to execute the film thickness detection method in the above-mentioned embodiment.

[0180] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems or devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0181] The computer-readable storage medium may be included in the electronic device, or may exist independently without being incorporated into the electronic device.

[0182] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by an electronic device, the electronic device: measures the tilt angle of the film to be measured and obtains a spectral interference signal of the film to be measured; analyzes the thickness of the film to be measured based on the spectral interference signal to obtain an error thickness of the film to be measured; and corrects the error thickness according to the tilt angle to obtain the actual thickness of the film to be measured.

[0183] Computer program code for performing the operations of the present application may be written in one or more programming languages, or a combination thereof, including object-oriented programming languages such as Java, Smalltalk, C++, and conventional procedural programming languages such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0184] The flow charts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, program segment or a part of code, and the module, program segment or a part of code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order than that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented by a dedicated hardware-based system that performs the specified function or operation, or can be implemented by a combination of dedicated hardware and computer instructions.

[0185] The modules described in the embodiments of the present application may be implemented in software or hardware, wherein the name of a module does not necessarily limit the unit itself.

[0186] The computer-readable storage medium provided in this application stores computer-readable program instructions (i.e., a computer program) for executing the aforementioned film thickness detection method. This computer-readable storage medium addresses the technical problem of reducing measurement errors caused by film tilt during film thickness measurement. Compared to the prior art, the beneficial effects of the computer-readable storage medium provided in this application are similar to those of the film thickness detection method provided in the aforementioned embodiments and are not further elaborated here.

[0187] The present application also provides a computer program product, comprising a computer program, which implements the steps of the above-mentioned film thickness detection method when executed by a processor.

[0188] The computer program product provided in this application can solve the technical problem of reducing measurement errors caused by film tilt during film thickness measurement. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as those of the film thickness detection method provided in the above-mentioned embodiment, and will not be elaborated here.

[0189] The above description is only part of the embodiments of the present application and does not limit the patent scope of the present application. All equivalent structural transformations made by using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A method for detecting film thickness, characterized in that: The film thickness detection method comprises: Measuring the tilt angle of the film to be measured and obtaining a spectral interference signal of the film to be measured, wherein the tilt angle includes the regional tilt angle of each region of the film to be measured; Analyzing the thickness of the film to be measured based on the spectral interference signal to obtain an error thickness of the film to be measured, wherein the error thickness includes a regional error thickness of each region of the film to be measured; For any target area in the film to be tested, determining the target area tilt angle and target area error thickness corresponding to the target area in the tilt angles of each area and the error thickness of each area, wherein the target area tilt angle includes the sub-area tilt angles of each sub-area in the target area, and the target area error thickness includes the sub-area error thickness of each sub-area in the target area; For any target sub-region in the film to be tested, determining the target sub-region tilt angle and the target sub-region error thickness corresponding to the target sub-region in the tilt angle of each sub-region and the error thickness of each sub-region, wherein the target sub-region tilt angle includes the horizontal axis tilt angle and the vertical axis tilt angle; determining a thickness correction parameter based on a product of a cosine value of the horizontal axis inclination angle and a cosine value of the vertical axis inclination angle; determining an actual thickness of the target subregion according to a product of the thickness correction parameter and the error thickness of the target subregion; After traversing each target sub-region, determining the actual thickness of the target region based on the actual thickness of each sub-region; After traversing each target area, the actual thickness of the film to be measured is determined based on the actual thickness of each area.

2. The film thickness detection method according to claim 1, wherein: The spectral interference signal includes regional spectral interference signals of each region of the film to be measured, wherein each regional spectral interference signal is obtained by relative motion of the film to be measured relative to the spectrometer, and the step of analyzing the thickness of the film to be measured based on the spectral interference signal to obtain the error thickness of the film to be measured includes: Analyzing the regional thickness of the corresponding region of the film to be measured based on any regional spectral interference signal to obtain the regional error thickness of the film to be measured in the corresponding region; The error thickness of the film to be measured is determined according to the error thickness of each area.

3. The film thickness detection method according to claim 1, wherein: The step of measuring the tilt angle of the film to be measured comprises: Controlling a reference plate of a preset tilt detection device to perform phase shift to obtain a tilt detection interference signal of the film to be measured, wherein the tilt detection interference signal is generated by light reflected from a first surface of the film to be measured and light reflected from a second surface of the preset reference plane; Phase unwrapping processing is performed on the tilt detection interference signal to obtain the tilt angle of the film to be measured.

4. The film thickness detection method according to claim 1, wherein: The step of obtaining the spectral interference signal of the film to be measured comprises: Invoking a preset broad-spectrum light source to illuminate the film to be tested, so that the film to be tested generates an interference signal to be received; The interference signal to be received that is focused by a preset telecentric objective lens is received by a spectrometer to obtain a spectral interference signal of the film to be measured.

5. A film thickness detection system, characterized in that: The film thickness detection system comprises: A detection module, configured to measure the tilt angle of the film to be measured and obtain a spectral interference signal of the film to be measured, wherein the tilt angle includes the regional tilt angle of each region of the film to be measured; an analysis module, configured to analyze the thickness of the film to be measured based on the spectral interference signal to obtain an error thickness of the film to be measured, wherein the error thickness includes a regional error thickness of each region of the film to be measured; A correction module is configured to determine, for any target area in the film to be tested, the target area tilt angle and the target area error thickness corresponding to the target area among the tilt angles of each area and the error thickness of each area, wherein the target area tilt angle includes the sub-area tilt angle of each sub-area in the target area, and the target area error thickness includes the sub-area error thickness of each sub-area in the target area; for any target sub-area in the film to be tested, determine the target sub-area tilt angle and the target sub-area error thickness corresponding to the target sub-area among the tilt angles of each sub-area and the error thickness of each sub-area, wherein the target sub-area tilt angle includes the horizontal axis tilt angle and the vertical axis tilt angle; determine a thickness correction parameter based on the product of the cosine value of the horizontal axis tilt angle and the cosine value of the vertical axis tilt angle; determine the sub-area actual thickness of the target sub-area according to the product of the thickness correction parameter and the target sub-area error thickness; after traversing each target sub-area, determine the region actual thickness of the target area based on the actual thickness of each sub-area; after traversing each target area, determine the actual thickness of the film to be tested based on the actual thickness of each region.

6. An electronic device, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the thin film thickness detection method according to any one of claims 1 to 4.

7. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the thin film thickness detection method according to any one of claims 1 to 4 are implemented.

Images