Chip stain detection method, device, computer equipment and storage medium

Abstract

The present invention discloses a chip stain detection method, device, computer equipment and storage medium, and belongs to the field of chip appearance detection technology. Aiming at the problem that tiny stains on the chip surface are difficult to detect and missed in the prior art, the present invention sets a digital image reconstruction distance, inputs a holographic image and a digital image reconstruction distance, calculates a spectrum diagram, performs frequency selection processing on the spectrum diagram to obtain a holographic reconstruction diagram, separates the holographic reconstruction diagram to obtain a reconstruction intensity diagram and a wrapping phase diagram, processes the wrapping phase diagram to obtain an unwrapping phase diagram, and judges whether there is a stain on the chip to be detected through the reconstruction intensity diagram. If there is a stain on the chip to be detected, the unwrapping phase diagram is used to judge whether the stain is an inner surface stain or an outer surface stain, thereby realizing rapid and accurate detection of tiny stains on the inner or outer surface of the chip, and effectively improving the efficiency and accuracy of chip stain detection.

Description

Technical Field

[0001] The present invention relates to the technical field of chip appearance detection, and more specifically, to a chip stain detection method, device, computer equipment and storage medium. Background Art

[0002] In the semiconductor chip production process, it is very important to detect internal and external stains after chip packaging. If there are stains on the chip, it may affect the quality and performance of the chip packaging, increase the failure rate of the product, and further affect the reliability and stability of the product. Therefore, early detection and removal of chip stains is crucial to ensure product quality. If there are stains on the chip, the product after chip packaging may need to be reworked or scrapped, increasing production costs. Therefore, by effectively detecting stains, unnecessary waste can be avoided, production costs can be reduced, product quality and reliability can be ensured, and the competitiveness and market share of enterprises can be improved.

[0003] In the prior art, the mainstream detection schemes are: (1) visual detection camera, which uses a high-resolution camera to photograph the surface of the chip after packaging, and detects the presence and location of stains through image processing algorithms. (2) infrared detection sensor, which uses an infrared sensor to detect the surface temperature change of the chip after packaging, thereby determining whether there is a stain. (3) ultraviolet detector, which uses an ultraviolet light source to illuminate the surface of the chip after packaging, and determines whether there is a stain by detecting the reflected or emitted ultraviolet light signal. (4) ultrasonic detection, which uses an ultrasonic sensor to detect the reflection of sound waves on the surface of the chip after packaging, thereby determining whether there is a stain. However, visual detection requires the use of a high-resolution camera, and the detection algorithm's requirements for computing power will be affected by dynamic blur during real-time dynamic measurement, and the detection of tiny stains inside the chip package is poor. In addition, due to the particularity of their equipment hardware, infrared, ultraviolet and ultrasonic detection have special requirements for installation and use, and the detection accuracy is limited. Slight white spots and stains inside the chip package are often missed. Therefore, the existing detection technology has complex equipment hardware, large space requirements, low detection accuracy, and may miss detection of tiny stains. Summary of the invention

[0004] 1. Technical problems to be solved

[0005] In view of the problem in the prior art that tiny stains on the chip surface are difficult to detect and may be missed, the present invention provides a chip stain detection method, device, computer equipment and storage medium, which can quickly and accurately detect tiny stains on the inner or outer surface of the chip, effectively improving the chip stain detection accuracy.

[0006] 2. Technical solution

[0007] The purpose of the present invention is achieved through the following technical solutions.

[0008] A chip stain detection method comprises the following steps:

[0009] Photographing the chip to be tested to obtain a holographic image;

[0010] Set the digital image reconstruction distance, input the holographic image and the digital image reconstruction distance, and calculate the spectrum diagram;

[0011] The spectrum image is processed by frequency selection to obtain a holographic reconstruction image, the holographic reconstruction image is separated to obtain a reconstruction intensity image and a wrapped phase image, and the wrapped phase image is processed to obtain an unwrapped phase image;

[0012] The reconstructed intensity map is used to determine whether there is stain on the chip to be detected. If there is stain on the chip to be detected, the unwrapped phase map is used to determine whether the stain is an inner surface stain or an outer surface stain.

[0013] Furthermore, the calculation formula of the spectrum diagram obtained by calculating the distance between the holographic image and the digital image reconstruction using the angular spectrum algorithm is:

[0014]

[0015] Among them, I s (x,y,d) represents the spectrum diagram, x represents the time domain horizontal axis, y represents the time domain vertical axis, f x represents the frequency domain horizontal coordinate, f y represents the frequency domain ordinate, i represents the complex imaginary part, λ represents the wavelength, d represents the digital image reconstruction distance, represents Fourier transform, E' R represents the reference wavefront, I H represents the holographic intensity map, and exp represents the exponential function.

[0016] Furthermore, the calculation formula for the holographic reconstruction image obtained by frequency selection processing of the spectrum image is:

[0017]

[0018] Where H represents the holographic reconstruction image, represents the inverse Fourier transform.

[0019] Furthermore, the real data of the complex data in the holographic reconstruction image are extracted, and the real data constitute a reconstruction intensity map; the imaginary data of the complex data in the holographic reconstruction image are extracted, and the imaginary data constitute a wrapped phase map.

[0020] Furthermore, the wrapped phase image is processed by the unwrapping algorithm to obtain the unwrapped phase image, and the calculation formula is:

[0021]

[0022] Among them, f c represents the complex fringe image, j represents the imaginary unit, represents the wrapped phase diagram, M represents the intensity coefficient, and f n Represents the normalized quality map.

[0023] Furthermore, in the reconstructed intensity map, the location of the stain on the chip to be tested is obtained.

[0024] Furthermore, the stain position is marked in the unwrapped phase image. If the stain height is higher than the plane position, the stain is judged to be an external surface stain; if the stain height is lower than the plane position, the stain is judged to be an internal surface stain; the plane position is the average value of the fitting plane of the surface glass of the chip to be tested.

[0025] A chip stain detection device, comprising:

[0026] Input module, photographing the chip to be tested to obtain a holographic image;

[0027] A calculation module is used to set the digital image reconstruction distance, input the holographic image and the digital image reconstruction distance, calculate and obtain the spectrum map, perform frequency selection processing on the spectrum map to obtain the holographic reconstruction map, separate the holographic reconstruction map to obtain the reconstruction intensity map and the wrapped phase map, and process the wrapped phase map to obtain the unwrapped phase map;

[0028] The judgment module judges whether there is stain on the chip to be tested by reconstructing the intensity map. If there is stain on the chip to be tested, it judges whether the stain is inner surface stain or outer surface stain by unwrapping the phase map.

[0029] A computer device comprises a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and the processor implements the above-mentioned method when executing the computer program.

[0030] A computer-readable storage medium stores a computer program, and the computer program executes the above method when executed by a processor.

[0031] 3. Beneficial effects

[0032] Compared with the prior art, the advantages of the present invention are:

[0033] (1) The chip stain detection method, device, computer equipment and storage medium of the present invention use a simple industrial camera with an optimized digital holographic imaging algorithm, have a compact structure, require little installation space, and can achieve fast and effective real-time detection of stains on the inner and outer surfaces of the chip. At the same time, by shooting the chip to be tested with a digital holographic camera with a holographic interference structure, high-resolution 2D images and high-precision 3D information can be obtained, which can more accurately detect the location and shape of the stain.

[0034] (2) The chip stain detection method, device, computer equipment and storage medium of the present invention can quickly identify tiny stains on the inner and outer surfaces of the chip after the chip is packaged, with high recognition accuracy, effectively avoiding the missed detection of tiny stains on the chip surface. At the same time, by using a digital holographic algorithm, it is possible to monitor the changes in stains in real time, and promptly discover and deal with the stains on the chip. In addition, it is also possible to realize automatic non-contact detection of chip stains, avoiding the safety risks caused by manual contact, greatly improving the detection efficiency and detection accuracy, and having strong practicality and wide applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a flow chart of a chip stain detection method according to an embodiment of the present invention;

[0036] Figure 2 This is a stain detection intensity diagram of the chip outer surface according to an embodiment of the present invention;

[0037] Figure 3 This is a contour diagram of stain detection on the outer surface of a chip according to an embodiment of the present invention;

[0038] Figure 4 This is a stain detection intensity diagram of the inner surface of the chip according to an embodiment of the present invention;

[0039] Figure 5 This is a contour diagram of stain detection on the inner surface of a chip according to an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0041] Example

[0042] like Figure 1As shown, a chip stain detection method provided by this embodiment includes the following steps: photographing the chip to be tested to obtain a holographic image; setting a digital image reconstruction distance, inputting the holographic image and the digital image reconstruction distance, and calculating a spectrum diagram; performing frequency selection processing on the spectrum diagram to obtain a holographic reconstruction diagram, separating the holographic reconstruction diagram to obtain a reconstructed intensity diagram and a wrapped phase diagram, and processing the wrapped phase diagram to obtain an unwrapped phase diagram; judging whether there is stain on the chip to be tested through the reconstructed intensity diagram, and if there is stain on the chip to be tested, judging whether the stain is an inner surface stain or an outer surface stain through the unwrapped phase diagram.

[0043] Specifically in this embodiment, the chip to be tested is first photographed to obtain a holographic image. In this embodiment, the chip to be tested is photographed by a digital holographic camera with a holographic interference structure to obtain a holographic image, that is, the holographic image is a source image collected by the digital holographic camera. Specifically, a fiber collimator is set in the digital holographic camera, and the fiber collimator is connected to the light source required by the digital holographic camera. In this embodiment, the light source required by the digital holographic camera can select any laser output by the fiber collimator. After the light source is connected, the beam splitter in the digital holographic camera evenly divides the light source into two coherent light beams. In this embodiment, the two coherent light beams are the first coherent light and the second coherent light. The first coherent light propagates in the direction of the original light path, and is reflected by the plane mirror in the digital holographic camera to obtain a reference light. The reference light and the first coherent light share the same light path but have opposite propagation directions. The second coherent light passes through the beam splitter prism and propagates in a direction perpendicular to the original light path, which is used to detect the chip to be tested. After collecting the information of the chip to be tested, the object light is obtained. The object light and the second coherent light share the same light path but have opposite propagation directions. Then, the object light and the reference light at the appropriate position are combined again by the beam splitter prism, that is, in this embodiment, the object light and the reference light at the position where coherent interference can be generated are combined by the beam splitter prism. After the object light and the reference light are combined by the beam splitter prism, the data information of the image of the chip to be tested obtained here is collected by the industrial camera in the digital holographic camera, and the data information constitutes the holographic image of the chip to be tested.

[0044] Therefore, the chip stain detection method provided in this embodiment uses a simple industrial camera with an optimized digital holographic imaging algorithm, has a compact structure, requires little installation space, and can achieve fast and effective real-time detection of stains on the inner and outer surfaces of the chip. At the same time, by shooting the chip to be tested with a digital holographic camera with a holographic interference structure, a high-resolution 2D image and high-precision 3D information can be obtained, which can more accurately detect the location and shape of the stain.

[0045] Furthermore, the digital image reconstruction distance is set, the holographic image and the digital image reconstruction distance are input, and the holographic image and the digital image reconstruction distance are calculated to obtain a spectrum diagram. In this embodiment, the angular spectrum algorithm is used to calculate the holographic image and the digital image reconstruction distance to obtain a spectrum diagram, and the calculation formula is:

[0046]

[0047] Among them, I s (x,y,d) represents the spectrum diagram, x represents the time domain horizontal axis, y represents the time domain vertical axis, f x represents the frequency domain horizontal coordinate, f y represents the frequency domain ordinate, i represents the complex imaginary part, λ represents the wavelength, d represents the digital image reconstruction distance, represents Fourier transform, E' R represents the reference wavefront, I H represents the holographic intensity map, and exp represents the exponential function.

[0048] It should be noted that the set digital image reconstruction distance d is the distance from the imaging plane to the reference plane in the holographic reconstructed image, and is also a key input for determining the quality of the holographic reconstructed image. Therefore, in this embodiment, the digital image reconstruction distance d needs to be set according to the position of the chip to be tested from the digital holographic camera.

[0049] Furthermore, the spectrum image is processed by frequency selection to obtain a holographic reconstruction image, and the real part data of the complex data in the holographic reconstruction image is extracted, and the real part data constitutes a reconstruction intensity image; the imaginary part data of the complex data in the holographic reconstruction image is extracted, and the imaginary part data constitutes a wrapped phase image. Specifically, in this embodiment, the calculation formula for obtaining the holographic reconstruction image by frequency selection of the spectrum image is:

[0050]

[0051] Where H represents the holographic reconstruction image, represents the inverse Fourier transform.

[0052] It should be noted that, in this embodiment, the frequency selection processing of the spectrum graph means that, according to the properties of the angular spectrum algorithm, there are three different spectrums on the spectrum graph obtained, namely, the 0-level spectrum, the positive 1-level spectrum and the negative 1-level spectrum. Among these three spectrums, the 0-level spectrum contains the relevant information of the light source, the positive 1-level spectrum and the negative 1-level spectrum contain the information of the holographic image, and are distributed in a mirror image. In this embodiment, since the chip to be tested is reconstructed, it is sufficient to select one of the positive 1-level spectrum or the negative 1-level spectrum.

[0053] After obtaining the holographic reconstruction image, the real part data of the complex data in the holographic reconstruction image is extracted, and the real part data constitutes the reconstruction intensity map, and the imaginary part data of the complex data in the holographic reconstruction image is extracted, and the imaginary part data constitutes the wrapped phase map. Specifically, in this embodiment, the data calculated for the holographic reconstruction image is complex data, wherein the real part data of the complex data constitutes the reconstruction intensity map, and the imaginary part data of the complex data constitutes the wrapped phase map. It should be noted that, in this embodiment, separating the holographic reconstruction image is a prior art.

[0054] For the wrapped phase image, in this embodiment, the wrapped phase image is processed by an unwrapping algorithm to obtain an unwrapped phase image, and the calculation formula is:

[0055]

[0056] Among them, f c represents the complex fringe image, j represents the imaginary unit, represents the wrapped phase diagram, M represents the intensity coefficient; f n Represents the normalized quality map.

[0057] In this embodiment, when searching the normalized quality map, the position with the highest quality is used as the starting pixel, and the pixels in its four neighborhoods are unpacked and put into the queue; as long as the queue is not empty, the pixel with the highest quality is removed from the queue, and the four neighborhoods of the pixel, the pixels that have not entered the queue and have not been unpacked, are unpacked and put into the queue; the above steps are repeated until the queue is empty, at which point all the pixels in the wrapped phase map have been unpacked. It should be noted that in this embodiment, the unpacking algorithm used is the prior art.

[0058] Furthermore, the reconstructed intensity map is used to determine whether there is a stain on the chip to be tested. If there is a stain on the chip to be tested, the unwrapped phase map is used to determine whether the stain is an inner surface stain or an outer surface stain. Specifically, first, in the reconstructed intensity map, the position of the stain on the chip to be tested is obtained, that is, the intensity data in the reconstructed intensity map can display an image, that is, the stain is found. After determining that there is a stain on the chip to be tested by the reconstructed intensity map, since the time domain in the reconstructed intensity map and the unwrapped phase map is in a one-to-one correspondence, that is, the data corresponding to the time domain coordinates (x, y) are all interrelated, therefore, the time domain coordinates (x, y) obtained in the reconstructed intensity map can be directly applied to the unwrapped phase map.

[0059] After the reconstructed intensity map transfers the position information to the unwrapped phase map, the stain position is marked in the unwrapped phase map to obtain a cross-sectional contour map of the stain position. It should be noted that the cross-sectional contour map of the stain position in the unwrapped phase map can be obtained by manual selection, or in the case of automatic detection, it is obtained by a cross-section in the horizontal direction of the stain's centroid position. Furthermore, the stain height data is obtained in the cross-sectional contour map of the stain position. In this embodiment, the stain height data is the direct data of the unwrapped phase map on the determined interception line. If the stain height is higher than the plane position, the stain is judged to be an external surface stain. If the stain height is lower than the plane position, the stain is judged to be an internal surface stain. It should be noted that in this embodiment, the plane position is the average value of the fitting plane of the surface glass of the chip to be tested.

[0060] In this embodiment, Figure 2 As shown in , when the stain on the chip to be tested is an external surface stain, the stain position can be observed by reconstructing the intensity map. Figure 3 As shown in Figure 1, at this time, the stain height is higher than the plane position. Figure 4 As shown in , when the stain on the chip to be tested is an inner surface stain, the stain position can be observed by reconstructing the intensity map. Figure 5 As shown, at this time, the stain height is lower than the plane position.

[0061] Therefore, in this embodiment, the intensity data in the reconstructed intensity map can display an image, that is, stains are found, and the wrapped phase map is unwrapped to determine whether the stains are on the inner surface or outer surface of the chip to be tested.

[0062] It should be noted that in this embodiment, if the relative difference between the stain height and the plane position is less than 0.5um, it is not identified as a stain, and there is no situation where the stain height and the plane position are on the same horizontal line. When the relative difference between the stain height and the plane position is higher than 2um, chip stain detection is required.

[0063] The chip stain detection method provided in this embodiment improves the setting accuracy of the input digital image reconstruction distance and the resolution of the holographic image. Therefore, in the actual production application process, it also has the ability to detect transmission samples such as chip packaging surface glass.

[0064] The chip stain detection method provided in this embodiment can quickly detect stains with a size range of not less than 2um inside and outside the chip package, that is, after the chip is packaged, it can quickly identify tiny stains inside and outside the chip, with high recognition accuracy, effectively avoiding the missed detection of tiny stains on the chip surface. At the same time, in this embodiment, by using a digital holographic algorithm, it is possible to monitor the changes of stains in real time, and promptly discover and deal with stains on the chip. In addition, it is also possible to realize automatic non-contact detection of chip stains, avoid the safety risks caused by manual contact, greatly improve the detection efficiency and detection accuracy, and have strong practicality and wide applicability.

[0065] The present embodiment also provides a chip stain detection device, including an input module, a calculation module and a judgment module. In the input module, the chip to be tested is photographed to obtain a holographic image. In the calculation module, the digital image reconstruction distance is set, the holographic image and the digital image reconstruction distance are calculated to obtain a spectrum diagram, the spectrum diagram is subjected to frequency selection processing to obtain a holographic reconstruction diagram, the holographic reconstruction diagram is separated to obtain a reconstruction intensity diagram and a wrapped phase diagram, and the wrapped phase diagram is processed to obtain an unwrapped phase diagram. In the judgment module, it is determined in the reconstructed intensity diagram whether there is a stain on the chip to be tested. If there is a stain on the chip to be tested, the unwrapped phase diagram is used to determine whether the stain is an inner surface stain or an outer surface stain. The chip stain detection device provided in the present embodiment can implement any of the chip stain detection methods, and the specific working process of a chip stain detection device can refer to the corresponding process in the chip stain detection method embodiment. The method and device provided in the present embodiment can be implemented in other ways. For example, the device embodiments described above are only illustrative; for example, the division of a module is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual connection or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or it can be an electrical, mechanical or other form of connection.

[0066] This embodiment also provides a computer device. A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the chip stain detection method when executing the computer program.

[0067] This embodiment also provides a computer-readable storage medium. A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, a chip stain detection method described in this embodiment is executed. The computer-readable storage medium can be any tangible medium containing or storing a program, which can be used by or in combination with an instruction execution system, device or device; the program code contained in the computer-readable medium can be transmitted using any appropriate medium, including but not limited to wireless, wire, optical cable, RF, etc., or any suitable combination of the above.

[0068] The above schematically describes the invention and its implementation methods, which is not restrictive. Without departing from the spirit or basic features of the invention, the invention can be implemented in other specific forms. What is shown in the accompanying drawings is only one of the implementation methods of the invention. The actual structure is not limited thereto, and any figure mark in the claims should not limit the claims involved. Therefore, if a person of ordinary skill in the art is inspired by it, without departing from the purpose of the invention, a structural method and an embodiment similar to the technical solution are designed without creativity, which should all belong to the protection scope of the present invention. In addition, the word "including" does not exclude other elements or steps, and the word "one" before the element does not exclude the inclusion of "multiple" elements. The multiple elements stated in the product claim can also be implemented by one element through software or hardware. The words first, second, etc. are used to indicate the name, and do not indicate any specific order.

Claims

1. A chip stain detection method, comprising the following steps: Photographing the chip to be tested to obtain a holographic image; Set the digital image reconstruction distance, input the holographic image and the digital image reconstruction distance, and calculate the spectrum diagram; The spectrum image is processed by frequency selection to obtain a holographic reconstruction image, the holographic reconstruction image is separated to obtain a reconstruction intensity image and a wrapped phase image, and the wrapped phase image is processed to obtain an unwrapped phase image; The reconstructed intensity map is used to determine whether there is a stain on the chip to be tested. If there is a stain on the chip to be tested, the unwrapped phase map is used to determine whether the stain is an inner surface stain or an outer surface stain. Specifically, after the reconstructed intensity map transfers the position information to the unwrapped phase map, the stain position is marked in the unwrapped phase map to obtain a cross-sectional contour map of the stain position, and the stain height data is obtained in the cross-sectional contour map of the stain position. If the stain height is higher than the plane position, the stain is determined to be an outer surface stain. If the stain height is lower than the plane position, the stain is determined to be an inner surface stain. The plane position is the average value of the fitting plane of the surface glass of the chip to be tested.

2. A chip stain detection method according to claim 1, characterized in that: The calculation formula of the spectrum obtained by calculating the distance between the holographic image and the digital image reconstruction using the angular spectrum algorithm is: Among them, I s (x,y,d) represents the spectrum diagram, x represents the time domain horizontal axis, y represents the time domain vertical axis, f x represents the frequency domain horizontal coordinate, f y represents the frequency domain ordinate, i represents the complex imaginary part, λ represents the wavelength, d represents the digital image reconstruction distance, represents Fourier transform, E R 'R represents the reference wavefront, I H represents the holographic intensity map, and exp represents the exponential function.

3. A chip stain detection method according to claim 2, characterized in that: The calculation formula for the holographic reconstruction image obtained by frequency selection of the spectrum image is: Where H represents the holographic reconstruction image, represents the inverse Fourier transform.

4. A chip stain detection method according to claim 3, characterized in that: The real data of the complex data in the holographic reconstruction image are extracted, and the real data constitute a reconstruction intensity map; the imaginary data of the complex data in the holographic reconstruction image are extracted, and the imaginary data constitute a wrapped phase map.

5. A chip stain detection method according to claim 4, characterized in that: The unwrapped phase image is processed by the unwrapped algorithm to obtain the unwrapped phase image. The calculation formula is: Among them, f c represents the complex fringe image, j represents the imaginary unit, represents the wrapped phase diagram, M represents the intensity coefficient, and f n Represents the normalized quality map.

6. A chip stain detection method according to claim 5, characterized in that: In the reconstructed intensity map, the location of the stain on the chip to be tested is obtained.

7. A chip stain detection method according to claim 6, characterized in that: Mark the stain position in the unwrapped phase image. If the stain height is higher than the plane position, the stain is judged to be an external surface stain; if the stain height is lower than the plane position, the stain is judged to be an internal surface stain; the plane position is the average value of the fitting plane of the surface glass of the chip to be tested.

8. A chip stain detection device, characterized in that: include: Input module, photographing the chip to be tested to obtain a holographic image; A calculation module is used to set the digital image reconstruction distance, input the holographic image and the digital image reconstruction distance, calculate and obtain the spectrum map, perform frequency selection processing on the spectrum map to obtain the holographic reconstruction map, separate the holographic reconstruction map to obtain the reconstruction intensity map and the wrapped phase map, and process the wrapped phase map to obtain the unwrapped phase map; The judgment module judges whether there is a stain on the chip to be tested by reconstructing the intensity map. If there is a stain on the chip to be tested, the unwrapped phase map is used to judge whether the stain is an inner surface stain or an outer surface stain. Specifically, after the reconstructed intensity map transfers the position information to the unwrapped phase map, the stain position is marked in the unwrapped phase map to obtain a cross-sectional contour map of the stain position, and the stain height data is obtained in the cross-sectional contour map of the stain position. If the stain height is higher than the plane position, the stain is judged to be an outer surface stain. If the stain height is lower than the plane position, the stain is judged to be an inner surface stain. The plane position is the average value of the fitting plane of the surface glass of the chip to be tested.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

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

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