Chip Detection System and Detection Production Line Based on Light Field Camera and Two-Dimensional Camera

Abstract

The present invention provides a chip detection system and a detection production line based on a light field camera and a two-dimensional camera. The two-dimensional camera is used to detect the solder balls of the chip, and the light field camera is used to detect the gold wires of the chip by using the gold wire detection method of the chip. The present invention combines the two-dimensional camera and the light field camera to realize a sequential detection method for the solder balls and gold wires of the chip, and obtains an overall solution for chip detection. The present invention uses the two-dimensional camera to photograph and detect the solder balls of the chip, and combines the gold wires of the chip detected by the light field camera to be able to detect defects such as wireless, broken wire, foot lifting, and wire deviation. The present invention can detect the defect of the gold wire falling of the chip by analyzing the wire height.

Description

Technical Field

[0001] The present invention relates to the technical field of two-dimensional and three-dimensional optoelectronic measurement of semiconductor chips, and particularly relates to a chip detection system and a detection production line based on a light field camera and a two-dimensional camera. Background Art

[0002] The current mainstream detection method in machine industrial vision still relies on 2D industrial cameras, that is, extracting the features of the object to be measured from a grayscale image and performing measurements in the X-Y plane.

[0003] When it comes to situations that require height measurement or Z-direction information, such as measuring height, depth, thickness, flatness, volume, wear, etc., 2D industrial vision is often powerless. Moreover, when the contrast of the grayscale image of the object to be measured is poor and the feature values of the object to be measured cannot be accurately extracted, feature extraction and measurement can often be considered through height segmentation. At this time, 3D industrial vision technology becomes an important detection means to solve the problems of machine industrial vision.

[0004] A light field camera is a new type of 3D camera that has emerged in recent years. A microlens array is added between the sensor and the main lens of a conventional camera (referring to a two-dimensional camera), and then the propagation direction of light is recorded, forming a unique light field image encoded by the lens array. By processing and rendering this light field image, three-dimensional information can be obtained.

[0005] Since the resolution in the X and Y directions is sacrificed during the imaging of a light field camera, the resolution of the light field multi-view image obtained even under a light field camera with a relatively high resolution is still not high.

[0006] The prior art has solved the technical problem of how to calibrate a light field camera.

[0007] Patent document CN106303175A discloses a virtual reality three-dimensional data acquisition method based on multi-views of a single light field camera, which includes the steps: S101, obtaining a microlens calibration map by using a single light field camera; S102, positioning the center position of the microlens by using the calibration map; S103, obtaining a light field picture; S104, selecting a certain pixel with the same relative position under each microlens in the light field image; S105, using the selected pixel as a sampling point, calculating the pixel values of the square matrix embedded therein, and then forming an image of one view; S106, selecting pixels at different positions, and repeating steps S103 to S105 until all pixels are selected.

[0008] Patent document CN111351446A discloses a calibration method for a light field camera used for three-dimensional topography measurement. It calibrates calibration plates at different positions in space and corresponding original light field images to obtain the corresponding relationship between the light field parallax image and three-dimensional space information; uses the light field camera to take multiple defocused soft-light solid-color calibration plates to obtain the light field white image; calculates the de-vignetting matrix based on the light field camera white image; and iteratively calculates the sub-pixel center coordinate matrix of the microlenses of the light field camera; the light field camera takes dot calibration plates at multiple known three-dimensional space positions and performs de-vignetting processing; establishes a light field mathematical model from three-dimensional coordinates to parallax, and fits and calculates the dot center coordinates and parallax values corresponding to the dot calibration according to the three-dimensional imaging law of the light field and the three-dimensional space information of the dots. The present invention can efficiently and accurately convert the light field parallax image into three-dimensional space information without main lens distortion.

[0009] Patent document CN111340888A discloses a calibration method and system for a light field camera without a white image. It first obtains the original light field image of an electronic checkerboard taken by the light field camera, and then calibrates the microlens array according to the original light field image to generate the calibration result of the microlens array and the center point grid of the microlens array; uses the template matching method to extract the line features of the original light field image and uses the line features as calibration data to calibrate the internal and external parameters of the projection model of the light field camera. It does not rely on a white image, and only needs to process the original light field of the checkerboard to obtain the center point grid of the microlens, the array attitude, and the internal and external parameters of the camera projection model, and has the characteristics of high calibration accuracy and wide adaptability of the light field camera.

[0010] However, the prior art cannot analyze and obtain gold wire defects well when dealing with the detection of gold wires. Summary of the Invention

[0011] Aiming at the defects in the prior art, the purpose of the present invention is to provide a chip detection system and a detection production line based on a light field camera and a two-dimensional camera.

[0012] According to a gold wire detection method for a chip provided by the present invention, it includes:

[0013] Gold wire positioning step: Obtain a detection image, locate paired solder balls in the detection image, and use the connection line between the paired solder balls as the basis for extracting the gold wire features, where the connection line is a straight line segment;

[0014] Gold wire feature extraction step: In the detection image, draw a perpendicular line to the straight line segment, and consider the points that meet the requirements among all the points on the perpendicular line as the points on the gold wire, denoted as gold wire feature points;

[0015] Gold wire defect analysis steps: Obtain the gold wire extension shape based on multiple gold wire feature points, and analyze the first type of defects of the gold wire according to the gold wire extension shape.

[0016] Preferably, in the gold wire positioning step, a three-dimensional image of the chip is obtained by a light field camera, and the central view image of the light field camera is used as the detection image.

[0017] In the gold wire defect analysis step, according to the three-dimensional image obtained by the light field camera, the gold wire feature points are converted into the three-dimensional space to obtain the wire height of the gold wire, and the second type of defects of the gold wire is analyzed according to the wire height.

[0018] Preferably, the gold wire feature extraction step includes:

[0019] Initialization step: Take the straight line segment as the currently selected segment; Trigger the execution of the perpendicular bisector step.

[0020] Perpendicular bisector step: Make a perpendicular bisector of the currently selected segment, and consider the points that meet the requirements among all the points on the perpendicular bisector as the points on the gold wire, denoted as gold wire feature points; Trigger the execution of the selection step.

[0021] Selection step: Take the two segments obtained by dividing the currently selected segment by the current perpendicular bisector as the two updated currently selected segments; Return to trigger the execution of the perpendicular bisector step.

[0022] Repeatedly trigger the execution of the perpendicular bisector step and the selection step until all the currently selected segments are less than the length threshold.

[0023] According to a chip detection method based on a light field camera and a two-dimensional camera provided by the present invention,

[0024] Use a two-dimensional camera to detect the solder balls of the chip;

[0025] Use a light field camera to detect the gold wire of the chip by using the gold wire detection method of the chip described above.

[0026] According to a gold wire detection system for a chip provided by the present invention, including:

[0027] Gold wire positioning module: Obtain a detection image, locate paired solder balls in the detection image, and use the connection line between the paired solder balls as the basis for gold wire feature extraction, wherein the connection line is a straight line segment.

[0028] Gold wire feature extraction module: In the detection image, make a perpendicular to the straight line segment, and consider the points that meet the requirements among all the points on the perpendicular as the points on the gold wire, denoted as gold wire feature points.

[0029] Gold wire defect analysis module: Obtain the gold wire extension shape based on multiple gold wire feature points, and analyze the first type of defects of the gold wire according to the gold wire extension shape.

[0030] Preferably, in the gold wire positioning module, a three-dimensional image of the chip is obtained by a light field camera, and the central view image of the light field camera is used as the detection image;

[0031] In the gold wire defect analysis module, according to the three-dimensional image obtained by the light field camera, the gold wire feature points are converted into a three-dimensional space to obtain the wire height of the gold wire, and the second type of defect of the gold wire is analyzed according to the wire height.

[0032] Preferably, the gold wire feature extraction module includes:

[0033] Initialization module: taking the straight line segment as the currently selected segment; triggering the perpendicular bisector module to execute;

[0034] Perpendicular bisector module: making a perpendicular bisector of the currently selected segment, and considering the points that meet the requirements among all the points on the perpendicular bisector as the points on the gold wire, denoted as gold wire feature points; triggering the selection module to execute;

[0035] Selection module: taking the two segments obtained by dividing the currently selected segment by the current perpendicular bisector as the two updated currently selected segments; returning to trigger the perpendicular bisector module to execute;

[0036] Repeatedly trigger the perpendicular bisector module and the selection module to execute until all the currently selected segments are less than the length threshold.

[0037] According to a chip detection system based on a light field camera and a two-dimensional camera provided by the present invention,

[0038] using a two-dimensional camera to detect the solder balls of the chip;

[0039] using the gold wire detection system of the chip with the light field camera to detect the gold wire of the chip.

[0040] According to a computer-readable storage medium storing a computer program, when the computer program is executed by a processor, the steps of the gold wire detection method of the chip are implemented, or the steps of the chip detection method based on a light field camera and a two-dimensional camera are implemented.

[0041] According to a product defect detection production line provided by the present invention, it includes the gold wire detection system of the chip, or includes the chip detection system based on a light field camera and a two-dimensional camera, or includes the computer-readable storage medium storing a computer program.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] 1. The present invention combines a two-dimensional camera and a light field camera to achieve an orderly detection method for the solder balls and gold wires of a chip, and obtains an overall solution for chip detection.

[0044] 2. The present invention uses the two-dimensional camera to photograph the solder balls of the detected chip, and combines the gold wires of the detected chip photographed by the light field camera, and can detect defects such as wireless, broken wire, lifted foot, and wire deviation.

[0045] 3. The present invention can detect the defect of the sagging wire of the gold wire of the chip by analyzing the wire height. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Other features, objects, and advantages of the present invention will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0047] Figure 1 It is a schematic structural diagram of the present invention.

[0048] Figure 2 It is a picture of the defect type of the gold wire being a sagging wire. Figure 2 a is a central perspective view under the light field camera, Figure 2 b is a depth map, Figure 2 c is a point cloud screenshot, Figure 2 d is a three-dimensional curve graph of the gold wire in the marked area.

[0049] Figure 3 It is a picture of the defect type of the gold wire being a broken wire. Figure 3 a is a central perspective view under the light field camera, Figure 3 b is a depth map, Figure 3 c is a point cloud screenshot, Figure 3 d is a three-dimensional curve graph of the gold wire in the marked area.

[0050] Figure 4 It is a picture of the defect type of the solder ball being a missing ball. Figure 4 a is a picture taken by the two-dimensional camera, Figure 4 b is a binary image after image processing.

[0051] Figure 5 is a picture of the defect type of the solder ball being a small ball. Figure 5a It is a picture taken by the two-dimensional camera, Figure 5b It is an image after image processing.

[0052] Figure 6 It is a flowchart of the method steps of the present invention.

[0053] Figure 7 It is a detection image.

[0054] Figure 8 It is a picture of each gold wire feature point in the detection image.

[0055] As shown in the figure:

[0056] Chip 100

[0057] Annular light 200 Detailed implementation manners

[0058] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all belong to the protection scope of the present invention.

[0059] An embodiment of the present invention provides a chip detection system based on a light field camera and a two-dimensional camera, aiming to realize various defect detections of semiconductor chips. Among them, a two-dimensional camera is used to detect the solder balls of the chip, and a light field camera is used to detect the gold wires of the chip by using a gold wire detection system of the chip.

[0060] As Figure 1 shown, a chip detection system based on a light field camera and a two-dimensional camera. The system includes: an object to be detected, a light source, a light field camera, and a two-dimensional camera. The object to be detected is a chip, and the specific detection objects are the solder balls and gold wires on the chip, and the corresponding detections are solder ball detection and gold wire detection. The light source is used to irradiate the object to be detected with light, such as annular light; the light field camera captures an image of the object to be detected to reconstruct the three-dimensional morphology of the gold wire of the chip and judge the gold wire defects; the two-dimensional camera captures the chip to detect the defects of the solder ball part of the chip.

[0061] The steps of the system include: using the light field camera with the aperture matched to capture multiple defocus soft light plates to perform light field white image calibration and complete the calibration of the center of the microlens; performing light field camera scale calibration and setting up the light source; using the light field camera to capture the semiconductor chip and process to obtain multi-view and depth images, and finally obtain the three-dimensional information of the object to be detected for gold wire detection; using the two-dimensional camera to capture the semiconductor chip to obtain the high-resolution two-dimensional information of the object to be detected for solder ball detection.

[0062] Specifically, a gold wire detection system for a chip according to the present invention includes:

[0063] Gold wire positioning module: Obtain the detection image, see Figure 7, pairs of solder balls are located in the detected image, and the line connecting the pairs of solder balls is used as the basis for gold wire feature extraction, where the line is a straight line segment; specifically, the pairs of solder balls refer to two solder balls directly connected by a gold wire in the design requirements. In a preferred example, the positions of the chip solder balls are obtained from a pre-set template. By matching the detected image with the template, the solder balls are obtained. Further preferably, the centers of the solder balls are obtained, and the line connecting the centers of the pairs of solder balls is used as the basis for gold wire feature extraction. Preferably, in the gold wire positioning module, a three-dimensional image of the chip is obtained by photographing the chip with a light field camera, and the central view image of the light field camera is used as the detected image.

[0064] Gold wire feature extraction module: In the detected image, draw a perpendicular line to the straight line segment, and consider the points that meet the requirements among all the points on the perpendicular line as the points on the gold wire, denoted as gold wire feature points; see Figure 8 .

[0065] Gold wire defect analysis module: Obtain the extended shape of the gold wire based on multiple gold wire feature points, and analyze the first type of defects of the gold wire according to the extended shape of the gold wire. The first type of defects includes no wire, broken wire, lifted foot, and wire deviation. In the gold wire defect analysis module, according to the three-dimensional image obtained by the light field camera, the gold wire feature points are converted into the three-dimensional space to obtain the wire height of the gold wire, and the second type of defects of the gold wire is analyzed according to the wire height. The second type of defects includes dropped wire. More specifically, no wire means the wire on the chip is missing, broken wire means the gold wire is broken, lifted foot is similar to broken wire, which is broken at the solder ball, and wire deviation means that the distance between the points on the gold wire and the line connecting the centers of the two solder balls exceeds a certain threshold, and the above three types of defects can be detected by the central view image obtained by photographing with a light field camera, that is, only the central view of the light field is required. However, dropped wire means that the height of the wire is significantly less than that of the normal wire. Therefore, when calculating dropped wire, the extracted feature points need to be converted into the 3D space through a scale calibration algorithm, calculate the wire height, and determine whether there is a dropped wire.

[0066] In a preferred example, the gold wire feature extraction module includes:

[0067] Initialization module: Take the straight line segment as the currently selected segment; trigger the perpendicular bisector module to execute;

[0068] Perpendicular bisector module: Draw a perpendicular bisector to the currently selected segment, and consider the points that meet the requirements among all the points on the perpendicular bisector as the points on the gold wire, denoted as gold wire feature points; trigger the selection module to execute;

[0069] Selection module: Take the two segments obtained by dividing the currently selected segment by the current perpendicular bisector as the two updated currently selected segments; return to trigger the perpendicular bisector module to execute;

[0070] Repeatedly trigger the perpendicular bisector module and the selection module to execute until all currently selected line segments are less than the length threshold.

[0071] For example, taking a gold wire as an example, connect the centers of two solder balls in a solder ball pair to form a straight line, then find the perpendicular bisector of this straight line, and look for points that meet a certain gray value on this perpendicular bisector. If the distance of this point from the midpoint of the straight line meets the requirements, then we consider it to be a point on the gold wire. Iterating in this way, many points on the gold wire can be obtained, and the gold wire features can be extracted accordingly.

[0072] More specifically, the calibration steps of the light field camera include the following steps:

[0073] Step A1: According to the area size and measurement depth range of the object to be measured, select an optical lens with a suitable focal length and magnification. Adjust the lens aperture of the microlens to match the aperture of the main lens of the light field camera, that is, the microlens aperture and the main lens aperture are matched. Specifically, it is manifested as the light field camera shooting a defocused soft-light solid color calibration plate image, in which the microlens array is exactly or close to a tangent state. A light field white image, or a light field camera white image, refers to a pure white background image taken by the light field camera. At this time, the shape of the microlens array will be particularly obvious on this image. Therefore, the aperture can be adjusted based on this image to ensure that the microlens images are exactly tangent. After adjustment, take multiple solid color background plates with relatively uniform light intensity at the defocused position of the light field camera, that is, defocused soft-light solid color calibration plates. After averaging and normalizing multiple light field white images, a de-vignetting matrix is obtained. All subsequent original light field images need to be divided by this de-vignetting matrix to complete the calibration of the light field white image. Here, the original light field image refers to the light field image that has not been processed by the light field multi-view image algorithm. Among them, u represents the abscissa value of the pixel in the image coordinate system, and v represents the ordinate value of the pixel in the image coordinate system. After completing the light field image calibration step, the light field white image is processed using a filter to remove the noise of the light field white image, and non-maximum suppression is performed on the filtered light field image; then, according to the processed image, the local maximum value is taken, and this maximum value is exactly the integer-level center of the microlens of the light field camera; using the integer-level microlens center as the initial iteration value, iteratively optimize the microlens arrangement grid, and finally obtain the angle and spacing of the microlens arrangement, and obtain the sub-pixel-level microlens center.

[0074] Step A2: The light field camera scale calibration step requires the assembly of a displacement stage and a scale calibration plate: First, fix the scale calibration plate in the focal plane area of the line array light field camera. Continuously move the calibration plate from the focal plane to a fixed spatial distance and take pictures. Since the spatial positions of the points on the calibration plate are known, the spatial positions of the points on the calibration plate during the entire movement process can be obtained. The dot calibration points will form a blur circle on the light field image. Process to obtain the diameter of the blur circle, and then calculate the parallax value of the blur circle and the pixel coordinates of the blur circle. According to the line array light field camera scale calibration model, fit the relationship between the three-dimensional coordinates in space, the pixel coordinates of the light field camera, and the parallax value.

[0075] Step A3: As Figure 1 shown, the light source irradiates the object to be measured from different angles, and the camera takes pictures of the object to be measured.

[0076] Step A4: Based on the original light field image, perform conventional light field rendering and depth estimation. First, perform light field multi-view rendering to obtain the light field multi-view image of the object to be measured; then further calculate to obtain the light field parallax image. According to the light field camera scale calibration result, convert the light field parallax image into a light field depth image. The depth information of the object to be measured is also in this depth image, so that three-dimensional imaging of the object to be measured can be performed.

[0077] Step A5: After obtaining the three-dimensional image of the chip, use the gold wire defect detection algorithm to obtain the defect type of the gold wire.

[0078] Step A6: Obtain the two-dimensional picture of the chip through a two-dimensional camera, and use the solder ball defect detection algorithm to obtain the defect type of the solder ball.

[0079] The present invention is attached with four specific embodiments. The first two examples are the gold wire defect detection gold wire defect embodiments of the light field camera, and the last two examples are the solder ball defect detection embodiments of the two-dimensional camera.

[0080] Figure 2 a is the central view under the light field camera, Figure 2 b is the depth map, Figure 2 c is the point cloud screenshot, Figure 2 d is the three-dimensional curve graph of the gold wire in the marked area. It can be judged from the three-dimensional curve graph that the defect type of the gold wire is a fallen wire.

[0081] Figure 3 a is the central view under the light field camera, Figure 3 b is the depth map, Figure 3 c is the point cloud screenshot, Figure 3 d is the three-dimensional curve graph of the gold wire in the marked area. It can be judged from the three-dimensional curve graph that the defect type of the gold wire is a broken wire.

[0082] Figure 4 a is the picture taken under the two-dimensional camera, Figure 4b is a binary image after image processing. Through the image, it can be judged that the defect type of the target area is lack of ball.

[0083] Figure 5a It is a picture taken under a two-dimensional camera. Figure 5b It is an image after image processing. Through the algorithm, the radius of the ball can be calculated. If it exceeds a certain threshold, it is judged as a large ball, and if it is less than a certain threshold, it will be judged as a small ball.

[0084] According to a computer-readable storage medium storing a computer program provided by the present invention, when the computer program is executed by a processor, it implements the steps of the gold wire detection method of the chip, or executes the steps of implementing the chip detection method based on a light field camera and a two-dimensional camera. The computer-readable storage medium can be a read-only or read-write memory such as a magnetic disk or an optical disk in devices such as a single-chip microcomputer, a DSP, a processor, a data center, a server, a PC, an intelligent terminal, a dedicated machine, and a light field camera.

[0085] According to a product defect detection production line provided by the present invention, it includes the gold wire detection system of the chip, or includes the chip detection system based on a light field camera and a two-dimensional camera, or includes the computer-readable storage medium storing a computer program.

[0086] According to a gold wire detection method of a chip provided by the present invention, it includes:

[0087] Gold wire positioning step: Obtain a detection image, locate paired tin balls in the detection image, and use the connection line between the paired tin balls as the basis for gold wire feature extraction, where the connection line is a straight line segment.

[0088] Gold wire feature extraction step: In the detection image, draw a perpendicular line to the straight line segment, and consider the points that meet the requirements among all the points on the perpendicular line as the points on the gold wire, denoted as gold wire feature points.

[0089] Gold wire defect analysis step: Obtain the gold wire extension shape according to multiple gold wire feature points, and analyze the first type of defect of the gold wire according to the gold wire extension shape.

[0090] Preferably, in the gold wire positioning step, a three-dimensional image of the chip is obtained by shooting the chip with a light field camera, and the central view image of the light field camera is used as the detection image.

[0091] In the gold wire defect analysis step, according to the three-dimensional image obtained by the light field camera, the gold wire feature points are converted into the three-dimensional space to obtain the wire height of the gold wire, and the second type of defect of the gold wire is analyzed according to the wire height.

[0092] Preferably, the gold wire feature extraction step includes:

[0093] Initialization step: Take the straight line segment as the currently selected segment; trigger the execution of the perpendicular bisector step;

[0094] Perpendicular bisector step: Construct the perpendicular bisector of the currently selected segment, and consider the points that meet the requirements among all the points on the perpendicular bisector as the points on the gold wire, denoted as the gold wire feature points; trigger the execution of the selection step;

[0095] Selection step: Take the two line segments obtained by dividing the currently selected segment by the current perpendicular bisector as the two updated currently selected segments; return and trigger the execution of the perpendicular bisector step;

[0096] Repeatedly trigger the execution of the perpendicular bisector step and the selection step until all the currently selected segments are less than the length threshold.

[0097] According to a chip detection method based on a light field camera and a two-dimensional camera provided by the present invention,

[0098] Use a two-dimensional camera to detect the solder balls of the chip;

[0099] Use a light field camera to detect the gold wire of the chip by using the gold wire detection method of the chip.

[0100] Those skilled in the art know that in addition to implementing the system, device and their respective modules provided by the present invention in the form of pure computer-readable program code, the method steps can be logically programmed to make the system, device and their respective modules provided by the present invention be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, embedded microcontrollers, etc. to implement the same program. Therefore, the system, device and their respective modules provided by the present invention can be regarded as a kind of hardware component, and the modules included therein for implementing various programs can also be regarded as the structures within the hardware component; the modules for implementing various functions can also be regarded as both software programs for implementing the method and the structures within the hardware component.

[0101] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined arbitrarily.

Claims

1. A method for detecting gold wires of a chip, characterized in that, Including: Gold wire positioning step: Obtain a detection image, locate paired solder balls in the detection image, and use the connection line between the paired solder balls as the basis for gold wire feature extraction, where the connection line is a straight line segment; Gold wire feature extraction step: In the detection image, draw a perpendicular line to the straight line segment, and consider the points that meet the requirements among all the points on the perpendicular line as the points on the gold wire, denoted as gold wire feature points; Gold wire defect analysis step: Obtain the gold wire extension shape based on multiple gold wire feature points, and analyze the first type of defect of the gold wire according to the gold wire extension shape; Use a light field camera to detect the gold wire of the chip.

2. The method for detecting the gold wire of a chip according to claim 1, characterized in that In the gold wire positioning step, a three-dimensional image of the chip is obtained by shooting the chip with a light field camera, and the central view image of the light field camera is used as the detection image; In the gold wire defect analysis step, according to the three-dimensional image obtained by the light field camera, the gold wire feature points are converted into the three-dimensional space to obtain the wire height of the gold wire, and the second type of defect of the gold wire is analyzed according to the wire height.

3. The gold wire detection method of the chip according to claim 1, characterized in that, The gold wire feature extraction step includes: Initialization step: Take the straight line segment as the currently selected segment; trigger the execution of the perpendicular bisector step; Perpendicular bisector step: Draw a perpendicular bisector to the currently selected segment, and consider the points that meet the requirements among all the points on the perpendicular bisector as the points on the gold wire, denoted as gold wire feature points; trigger the execution of the selection step; Selection step: Take the two segments obtained by dividing the currently selected segment by the current perpendicular bisector as the two updated currently selected segments; return to trigger the execution of the perpendicular bisector step; Repeatedly trigger the execution of the perpendicular bisector step and the selection step until all the currently selected segments are less than the length threshold.

4. A gold wire detection system for a chip, characterized in that, Including: Gold wire positioning module: Obtain a detection image, locate paired solder balls in the detection image, and use the connection line between the paired solder balls as the basis for gold wire feature extraction, where the connection line is a straight line segment; Gold wire feature extraction module: In the detection image, draw a perpendicular line to the straight line segment, and consider the points that meet the requirements among all the points on the perpendicular line as the points on the gold wire, denoted as gold wire feature points; Gold wire defect analysis module: Obtain the gold wire extension shape based on multiple gold wire feature points, and analyze the first type of defect of the gold wire according to the gold wire extension shape; Use a light field camera to detect the gold wire of the chip.

5. The system for detecting the gold wire of a chip according to claim 4, characterized in that In the gold wire positioning module, a three-dimensional image of the chip is obtained by shooting the chip with a light field camera, and the central view image of the light field camera is used as the detection image; In the gold wire defect analysis module, according to the three-dimensional image obtained by the light field camera, the gold wire feature points are converted into the three-dimensional space to obtain the wire height of the gold wire, and the second type of defect of the gold wire is analyzed according to the wire height.

6. The gold wire detection system for the chip according to claim 4, characterized in that, The gold wire feature extraction module includes: Initialization module: Take the straight line segment as the currently selected segment; trigger the execution of the perpendicular bisector module; Perpendicular bisector module: Draw a perpendicular bisector to the currently selected segment, and consider the points that meet the requirements among all the points on the perpendicular bisector as the points on the gold wire, denoted as gold wire feature points; trigger the execution of the selection module; Selection module: Take the two line segments obtained by dividing the currently selected line segment by the current perpendicular bisector as the two currently selected line segments after update; return to trigger the execution of the perpendicular bisector module. Repeatedly trigger the execution of the perpendicular bisector module and the selection module until all the currently selected line segments are shorter than the length threshold.

7. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the gold wire detection method for the chip described in any one of claims 1 to 3.

8. A product defect detection production line, characterized in that, It includes the gold wire detection system for the chip described in any one of claims 4 to 6, or includes the computer-readable storage medium storing the computer program described in claim 7.

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