VDMOS manufacturing method

Abstract

This invention provides a method for manufacturing VDMOS. The method acquires an initial image of the VDMOS under test, determines the device model and pin count of the VDMOS based on the initial image, and obtains preset detection points and corresponding preset pressures on each pin according to the device model. Based on the preset detection points and preset pressures, the pressure heads in the upper and lower test groups are controlled to perform upper and lower compression tests on the pins of the VDMOS under test, obtaining a first detection result. Then, the pressure heads in the left and right test groups are called to perform left and right compression tests on the pins corresponding to the first detection result, obtaining a second detection result. This invention automatically matches test parameters by identifying the device model, and utilizes physical compression in the upper and lower and left and right directions combined with image analysis to detect the state of the pins under stress, thereby identifying pin defects and achieving the detection of the physical quality of the manufactured VDMOS.

Description

Technical Field

[0001] This invention relates to data processing technology, and more particularly to a method for manufacturing a VDMOS. Background Technology

[0002] VDMOS, as a high-performance power device, plays a crucial role in power management, automotive electronics, and industrial automation control due to its superior switching characteristics and thermal stability. During the manufacturing and packaging process of VDMOS, the pins, as the physical carriers connecting the device to external circuits, directly determine the reliability of the device in subsequent soldering assembly and long-term operation due to their molding quality, mechanical strength, and the stability of their connection with the package body.

[0003] Currently, quality inspection of VDMOS pins primarily employs Automated Optical Inspection (AOI) technology, which uses high-precision cameras to capture images and analyze pin coplanarity, spacing, and bending. However, this vision-based inspection method is a non-contact visual screening, only able to determine whether the pin's static geometric profile meets standards, and cannot perceive the pin's mechanical and physical properties. In actual production, some pins, while appearing normal, may have hidden defects such as loose root molding, insufficient material internal stress, or poor resistance to deformation. When these devices are subjected to pressure from placement machines or vibration in the working environment during subsequent processes, pin deformation or poor contact is highly likely. Existing single-vision inspection methods cannot identify such potential mechanical strength defects under non-stress conditions, leading to products with quality risks flowing into the next stage.

[0004] Therefore, how to conduct multi-dimensional physical stress tests on VDMOS pins to verify their mechanical strength and stability has become an urgent problem to be solved in the current VDMOS manufacturing and testing field. Summary of the Invention

[0005] This invention provides a method for manufacturing VDMOS, which can perform multi-dimensional physical stress tests on VDMOS pins to verify the mechanical strength and stability of the pins.

[0006] A first aspect of the present invention provides a method for manufacturing a VDMOS, comprising: An initial image of the VDMOS under test is acquired using an image acquisition device, and the device model and pin count of the VDMOS under test are determined based on the initial image. According to the device model, obtain the preset detection points on each pin, and based on the preset detection points, obtain the preset pressure corresponding to the pressure head in the upper and lower test groups and the left and right test groups from the preset point pressure reference table; Based on the number of pins, preset detection points, and preset pressure, the pressure head in the upper and lower test group is controlled to perform an upper and lower squeezing test on the pins of the VDMOS under test, and the first detection result is obtained. Based on the first test result, preset test points, and preset pressure, the pressure head in the left and right test groups is called to perform left and right squeezing tests on the first test pin of the VDMOS under test, and the second test result is obtained.

[0007] Optionally, in one possible implementation of the first aspect, the step of controlling the pressure head in the upper and lower test group to perform an upper and lower compression test on the pins of the VDMOS under test based on the number of pins, preset detection points, and preset pressure to obtain a first detection result includes: The upper and lower test groups include an upper test group and a lower test group, and the upper pressure head arranged in sequence in the upper test group and the lower pressure head arranged in sequence in the lower test group are obtained; Based on the number of pins, select an equal number of upper pressure heads as the first pressure heads in the upper test group. According to the preset detection points and preset pressure, call the first pressure heads to press the pins downwards, and call the image acquisition device to acquire the upper test image at the end of the pressing. Compare the upper test image with the initial image to obtain the first intermediate result. Based on the first intermediate result, a second pressure head is selected. Based on the preset detection point and preset pressure, the second pressure head is used to press the pin corresponding to the first intermediate result upward to obtain the first detection result.

[0008] Optionally, in one possible implementation of the first aspect, the comparison of the test image and the initial image to obtain the first intermediate result includes: The contours of each pin are extracted from the initial image as the initial contours, and the area of ​​the initial contours is obtained as the initial area. Extract the contours of each pin from the above test image as the above test contour, and obtain the area of ​​the above test contour as the above test area. Map the initial image onto the upper test image, compare the initial area of ​​each pin with the upper test area, and select the pins whose initial area is greater than or equal to the upper test area as the initial selection pins. The intersection area of ​​the initial contour of the initial selected pin and the upper test contour is obtained as the initial selection area. The area of ​​the initial selection area is determined as the initial selection area. The initial selection area is compared with the preset standard area range, and the initial selected pins whose initial selection area is within the standard area range are extracted as the first intermediate result.

[0009] Optionally, in one possible implementation of the first aspect, the step of selecting a second pressure head based on the first intermediate result, and then using the second pressure head to press the pin corresponding to the first intermediate result upward based on a preset detection point and a preset pressure to obtain a first detection result includes: The initial pins corresponding to the first intermediate results are obtained as the first intermediate pins. The number of the first intermediate pins is determined as the first intermediate number. Based on the first intermediate number, an equal number of pressure heads are selected in the next test group as the second pressure heads. According to the preset detection points and preset pressure, the second pressure head is called to squeeze the first intermediate pin upward, and the image acquisition device is called to acquire the lower test image at the end of the squeezing. Based on the lower test image, the contour of each first intermediate pin is extracted as the lower test contour, and the area of ​​the lower test contour is obtained as the lower test area. The initial image is mapped onto the next test image. The initial area of ​​the first intermediate pin and the area of ​​the next test are compared. The first intermediate pin with an initial area greater than or equal to the area of ​​the next test is selected as the next selected pin. The intersection of the initial contour and the lower test contour of the reselected pin is obtained as the reselected region. The area of ​​the reselected region is determined as the reselected area. The reselected area is compared with the preset standard area range. The reselected pins whose reselected area is within the standard area range are extracted as the first detection result.

[0010] Optionally, in one possible implementation of the first aspect, the step of calling the pressure head in the left and right test groups to perform a left and right squeezing test on the first detection pin of the VDMOS under test based on the first detection result, the preset detection point, and the preset pressure, to obtain the second detection result, includes: The left and right test groups include a left test group and a right test group, and the left pressure head arranged in sequence in the left test group and the right pressure head arranged in sequence in the right test group are obtained; The reselected pin corresponding to the first detection result is used as the first detection pin, and the number of the first detection pins is determined as the first detection quantity. Based on the first detection quantity, select an equal number of left pressure heads in the left test group as the third pressure heads. According to the preset detection point and preset pressure, call the third pressure head to squeeze the first detection pin to the right, and call the image acquisition device to acquire the left test image at the end of the squeezing. Compare the left test image with the initial image to obtain the second intermediate result. Based on the second intermediate result, the right pressure head is selected to obtain the fourth pressure head. Based on the preset detection point and preset pressure, the fourth pressure head is called to squeeze the first detection pin corresponding to the second intermediate result to the left to obtain the second detection result.

[0011] Optionally, in one possible implementation of the first aspect, the comparison of the left test image and the initial image to obtain the second intermediate result includes: The contours of each first detection pin are extracted from the left test image as the left test contours; Obtain the boundary line on the left test contour that overlaps with the package body as the left test boundary, and extract the boundary line on the initial contour that overlaps with the package body as the initial boundary. The initial image is mapped onto the left test image, and the left test contour corresponding to the left test boundary that coincides with the initial boundary is selected as the initial screening contour. The area of ​​the intersection region between the initial screening profile and the corresponding initial profile is obtained as the initial screening area. The initial screening area is compared with the preset approved area range, and the first detection pin whose initial screening area is within the approved area range is extracted as the second intermediate result.

[0012] Optionally, in one possible implementation of the first aspect, the step of selecting a fourth pressure head based on the second intermediate result, and then using the fourth pressure head to press the first detection pin corresponding to the second intermediate result to the left based on a preset detection point and a preset pressure to obtain a second detection result, includes: The first detection pin corresponding to the second intermediate result is obtained as the second intermediate pin, the number of the second intermediate pins is determined as the second intermediate number, and based on the second intermediate number, an equal number of right pressure heads are selected in the right test group as the fourth pressure head. According to the preset detection points and preset pressure, the fourth pressure head is called to squeeze the second middle pin to the left, and the image acquisition device is called to acquire the right test image at the end of the squeezing. The contours of each second intermediate pin are extracted from the right test image as the right test contours, and the boundary lines that overlap with the package body on the right test contours are obtained as the right test boundaries. Map the initial image onto the right test image, and select the right test contour corresponding to the right test boundary that coincides with the initial boundary as the rescreening contour; The area of ​​the intersection region between the rescreening contour and the corresponding initial contour is obtained as the rescreening area. The rescreening area is compared with the preset approved area range, and the second intermediate pin that is within the approved area range is extracted as the second detection result.

[0013] Optionally, in one possible implementation of the first aspect, it also includes: The pressure value of the indenter performing the extrusion test in the left and right test groups is continuously monitored by the pressure monitoring device. When it is determined that there is a pressure head with a pressure value of zero, the corresponding pressure head is obtained as the selected pressure head, and the maximum pressure of the selected pressure head for performing the extrusion test is retrieved based on the pressure monitoring device as the critical pressure; The critical difference is obtained by calculating the ratio of the critical difference to the preset pressure and the critical pressure. The length of the pressure head in the left and right test groups is used as the initial length. The extension length is obtained by multiplying the initial length by the pressure ratio. The selected pressure head is extended based on the stated extension length.

[0014] A second aspect of the present invention provides an electronic device comprising: a memory, a processor, and a computer program, the computer program being stored in the memory, and the processor executing the computer program to perform the methods described in the first aspect of the present invention and various possible methods related to the first aspect.

[0015] A third aspect of the present invention provides a storage medium storing a computer program, which, when executed by a processor, is used to implement the first aspect of the present invention and various methods possibly involved in the first aspect.

[0016] The beneficial effects of this invention are as follows: 1. This invention acquires an initial image of the VDMOS under test, identifies the device model and pin count, automatically retrieves the corresponding preset detection points and preset pressures based on the device model, and controls the upper and lower test groups and the left and right test groups to sequentially perform vertical and horizontal physical compression tests on the pins. By actively applying multi-dimensional physical stress and combining it with image analysis, this invention can identify mechanical defects that cannot be detected by static visual inspection, such as loose pin roots, insufficient internal material stress, or insufficient resistance to deformation, thus achieving multi-dimensional detection of the physical connection reliability of the finished VDMOS product.

[0017] 2. In the upward and downward compression test of this invention, the upper test group is first used for downward compression, and then the lower test group is used for upward compression. First, during the upper test group test, pins that did not detach from the package body due to compression are screened by comparing the contour areas of the pins before and after compression. Then, pins that did not undergo excessive deformation are screened by calculating the area of ​​the intersection region between the initial contour and the upper test contour. Pins that pass the upper test group test continue to be tested by the lower test group, and a new round of screening is performed based on the lower test group. This scheme identifies whether a pin detaches from the package body under force by using the contour area, verifies whether the elastic deformation of the pin meets the standard by using the area of ​​the intersection region, and verifies the mechanical stability of the pin in the vertical direction using bidirectional testing, preventing missed detections due to unidirectional testing and ensuring the connection stability of the pins under vertical pressure.

[0018] 3. In the left and right compression tests of this invention, the left test group is first called to compress to the right, and then the right test group is called to compress to the left. First, during the test in the left test group, the overlap of the pin's contour boundaries before and after compression is compared to determine if the pin has shifted laterally. Then, the area of ​​the intersection region between the initial contour and the left test contour is calculated to screen pins that have not undergone excessive deformation. Pins that pass the left test group test continue to be tested in the right test group, and a new round of screening is performed based on the right test group. Simultaneously, this invention monitors the pressure of the indenter in real time. When an abnormal pressure drop to zero is detected, the extension length is calculated based on the critical pressure to compensate for the extension of the indenter. This invention uses boundary lines to identify overall root loosening of the pin, verifies whether the elastic deformation of the pin meets the standard by using the area of ​​the intersection region, and verifies the mechanical stability of the pin in the horizontal direction using bidirectional left and right testing, thus realizing the detection of the pin's lateral shear resistance performance. Attached Figure Description

[0019] Figure 1 A flowchart illustrating a method for manufacturing a VDMOS provided by the present invention; Figure 2 This is a schematic diagram of the structure in which the first pressure head presses the pin in this invention; Figure 3 This is a schematic diagram of the structure of the initially selected region in this invention; Figure 4 This is a schematic diagram of the structure in which the third pressure head presses against the first detection pin in this invention; Figure 5 This is a schematic diagram of the hardware structure of an electronic device provided by the present invention. Detailed Implementation

[0020] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0021] This invention provides a method for manufacturing VDMOS, such as... Figure 1 As shown, it includes: S1. Acquire an initial image of the VDMOS under test using an image acquisition device, and determine the device model and pin count of the VDMOS under test based on the initial image.

[0022] It should be noted that in existing technologies, quality inspection of VDMOS pins primarily employs automated optical inspection (AOI) technology. This involves using a high-precision camera to capture images and analyze the pin's coplanarity, spacing, and curvature. However, this vision-based inspection method is a non-contact visual screening method that can only determine whether the pin's geometric contour conforms to standards in a static state, and cannot perceive the pin's mechanical and physical properties. In actual production, some pins, although appearing normal, may have hidden defects such as loose root molding, insufficient material internal stress, or poor resistance to deformation. When these devices are subjected to pressure from a placement machine in subsequent processes or vibration in the working environment, pin deformation or poor contact can easily occur.

[0023] Therefore, this invention proposes a method for multi-dimensional physical stress testing of VDMOS pins. By squeezing in the up-down and left-right directions, the mechanical strength and stability of the pins are verified, thereby accurately rejecting products with unqualified mechanical performance. Furthermore, the extracted unqualified pins can be specifically analyzed to improve subsequent manufacturing processes.

[0024] Understandably, VDMOS power devices come in various package specifications (such as TO-220, TO-247, DIP, etc.), and these different specifications vary significantly in size, pin distribution, and mechanical strength tolerance. This step involves visually identifying the device model of the VDMOS under test before testing begins, and further identifying the number of pins. This is done to enable adaptive adjustments to the testing process, ensuring that subsequent mechanical extrusion testing accurately matches test parameters to the specific device model, thereby achieving efficient and safe automated wire mixing detection.

[0025] Specifically, after placing the VDMOS under test on the test station, a high-resolution image of the area where the VDMOS is located is acquired using an image acquisition device as the initial image. This initial image is then preprocessed (e.g., grayscale conversion, noise reduction, binarization) to remove background interference. This initial image is taken from a top-down angle, allowing observation of pin changes before and after testing. Based on the initial image, on one hand, OCR (Optical Character Recognition) technology is used to extract character information from the surface of the package body, or a template matching algorithm is used to compare the outer contour of the device with a pre-stored standard template library to determine the device model of the VDMOS under test. On the other hand, edge detection algorithms (such as the Canny operator) are used to identify the contrast between the metallic luster area of ​​the pins and the background, extracting the geometric contours of the pins. A counting algorithm is then used to count the number of independent pin contours to obtain the pin count.

[0026] Here, "VDMOS under test" refers to the VDMOS whose pins are to be tested; "image acquisition device" refers to an industrial-grade high-definition camera (such as a CCD or CMOS camera) installed directly above the test station; "initial image" refers to the original image of the VDMOS in a stationary state before the test begins, which includes the complete package body and pin distribution; "device model" refers to the model of the VDMOS under test, which is a unique identifier used to distinguish the VDMOS's specifications; and "pin count" refers to the total number of metal conductive pins actually extending from one or both sides of the VDMOS under test.

[0027] S2, according to the device model, obtain the preset detection points on each pin, and based on the preset detection points, obtain the preset pressure corresponding to the pressure head in the upper and lower test groups and the left and right test groups from the preset point pressure reference table.

[0028] It should be noted that VDMOS, as a precision power device, varies in lead material, width, and package holding force among different models. If a uniform pressure is used for blind testing, excessive pressure may break the leads of low-power devices or damage internal gold wire connections, while insufficient pressure may not effectively affect the leads of high-power devices, leading to missed faulty solder joints. Furthermore, whether the pressure is applied to the root or tip of the lead generates completely different torques, thus affecting the accuracy of the test results.

[0029] Understandably, this step intelligently retrieves specific test parameters based on the device model identified in step S1, ensuring the effectiveness and safety of the test and ensuring that the applied physical stress is within a range that can detect defects without damaging qualified products.

[0030] Specifically, the database of preset test points is accessed using the device model as an index. Because different VDMOS models have variations in pin count, length, spacing, and material strength, their critical stress areas differ, requiring matching specific test points based on the device model. Preset test points for each pin are extracted from the database based on the device model, and the differences between the upper / lower test groups and the left / right test groups must be distinguished. Specifically, the upper / lower test points target the vertical force direction of the pin, while the left / right test points target the horizontal force direction.

[0031] Furthermore, the acquired preset detection points are used as secondary indexes to query the preset point pressure reference table. The point pressure reference table stores the safe pressure threshold (i.e. preset pressure) corresponding to each preset detection point when performing up-down and left-right tests. The preset pressure corresponding to the pressure head of the up-down test group and the left-right test group can be directly matched.

[0032] Among them, the preset test point refers to the optimal position for contact between the indenter and the pin, determined according to the geometry of the VDMOS, usually set in the middle of the pin or in a force-sensitive area; the point pressure reference table is a pre-established standardized data table that records the preset pressure corresponding to the preset test point when performing vertical and horizontal extrusion tests, and also associates it with the equipment model; the preset pressure refers to the preset indenter extrusion force threshold for the preset test point and test group type (vertical and horizontal test group); the vertical test group refers to the test components that perform vertical extrusion tests, including the upper test group located above the pin of the VDMOS under test and the lower test group located below the pin of the VDMOS under test. The lower test group is located below the S-pin; the left and right test groups refer to the test components that perform horizontal compression tests, including the left test group which acts on the left side of the VDMOS pin under test and the right test group which acts on the right side of the VDMOS pin under test; the pressure head is the execution component that performs the compression test and is the basic unit of the upper and lower test groups and the left and right test groups. It is used to apply a preset pressure to the pin of the VDMOS under test. It is usually made of a material with high hardness, wear resistance and insulating properties. Its contact surface width is usually less than or equal to the pin width. The pressure head can be controlled by the drive component to move in the up and down direction, as well as in the left and right direction. The pressure head can be an insulating probe, a metal pressure rod, etc.

[0033] S3, based on the number of pins, preset detection points, and preset pressure, control the pressure head in the upper and lower test group to perform upper and lower squeezing tests on the pins of the VDMOS under test, and obtain the first detection result.

[0034] The upper and lower compression test refers to the process of first pressing the pin downward with the upper pressure head and then pressing the pin upward with the lower pressure head; the first test result refers to the set of qualified pins selected after the upper and lower compression test.

[0035] In some embodiments, step S3 (based on the number of pins, preset detection points, and preset pressure, controlling the pressure head in the upper and lower test group to perform an upper and lower squeezing test on the pins of the VDMOS under test to obtain a first detection result) includes S31-S33: S31, the upper and lower test groups include an upper test group and a lower test group, and the upper pressure head arranged in sequence in the upper test group and the lower pressure head arranged in sequence in the lower test group are obtained.

[0036] It should be noted that mechanical failures of VDMOS pins typically vary depending on the direction of force applied. For example, a pin may be stable under downward pressure due to packaging defects, but easily bend or detach from the package under upward pressure. Therefore, testing in a single direction cannot fully expose the problem.

[0037] Therefore, the upper and lower test groups of the present invention include an upper test group for applying downward pressure and a lower test group for applying upward thrust, and the upper test group includes a plurality of upper pressure heads arranged in sequence, and the lower test group includes a plurality of lower pressure heads arranged in sequence.

[0038] The upper test group refers to the sub-unit responsible for applying downward pressure in the upper and lower test groups. It consists of multiple upper pressure heads arranged in sequence at preset intervals. The upper test group can carry the upper pressure heads and move them downward in the vertical direction to apply pressure to the pin. The lower test group refers to the sub-unit responsible for applying upward pressure in the upper and lower test groups. It consists of multiple lower pressure heads arranged in sequence at preset intervals. The lower test group can carry the lower pressure heads and move them upward in the vertical direction to apply pressure to the pin. The upper pressure head refers to the pressure head in the upper test group, and the lower pressure head refers to the pressure head in the lower test group. The upper and lower pressure heads can not only move in the vertical direction to apply pressure, but also move in the horizontal direction. The horizontal position movement is for position adjustment according to preset detection points.

[0039] S32, based on the number of pins, select an equal number of upper pressure heads as the first pressure heads in the upper test group, call the first pressure heads to press the pins downward according to the preset detection points and preset pressure, and call the image acquisition device to acquire the upper test image at the end of the pressing, compare the upper test image with the initial image to obtain the first intermediate result.

[0040] It should be noted that this example is the first stage of the top and bottom compression test (downward compression), which identifies whether the pin detaches or deforms excessively when subjected to vertical force. Specifically, if the molding bond at the pin root is insufficient, the pin may extend outward from the package body under vertical pressure. In a top-down view, this extension manifests as an increase in the pin's outline area. If the pin material is not strong enough, it will bend downward significantly under pressure, and its outline will shrink excessively in the image, directly exceeding the preset conditions.

[0041] It is understandable that, such as Figure 2 As shown, based on the number of pins, an equal number of upper pressure heads are selected as the first pressure heads to achieve a one-to-one match between the pins and the first pressure heads. Combined with preset detection points and preset pressure, the first pressure heads are driven to perform downward compression on all pins. At the end of the compression, the pressure is maintained and the upper test image is acquired. The upper test image is compared with the initial image, and the pins with qualified deformation are selected as the first intermediate result.

[0042] The upper test image refers to the top view image of the VDMOS under test taken by the image acquisition device when the first pressure head completes downward pressing; the first intermediate result refers to the set of pins with qualified deformation selected by comparing the upper test image with the initial image.

[0043] In some embodiments, step S32 (comparing the test image and the initial image to obtain a first intermediate result) includes S321-S324: S321: Extract the contours of each pin based on the initial image as the initial contour, and obtain the area of ​​the initial contour as the initial area.

[0044] It is easy to understand that the initial image acquired in step S1 is processed, and edge detection operators (such as Canny or Sobel) are used to identify the pin edges, generate a closed initial contour, and calculate the number of pixels inside it to obtain the initial area.

[0045] The initial contour refers to the contour of a single pin obtained based on the initial image, and the initial area refers to the actual area of ​​the pixel region enclosed by the initial contour.

[0046] S322: Extract the contours of each pin from the upper test image as the upper test contour, and obtain the area of ​​the upper test contour as the upper test area.

[0047] It is easy to understand that, referring to step S321, the upper test image is processed, the outline of each pin in the upper test image is extracted as the upper test outline, and its area is calculated as the upper test area.

[0048] Among them, the upper test profile refers to the profile of a single pin obtained based on the upper test image, and the upper test area refers to the actual area corresponding to the pixel region enclosed by the upper test profile.

[0049] S323 maps the initial image onto the upper test image, compares the initial area of ​​each pin with the upper test area, and selects the pin with an initial area greater than or equal to the upper test area as the initial selected pin.

[0050] It is understandable that both the initial image and the upper test image are acquired by an image acquisition device, therefore the image sizes of the initial image and the upper test image are the same, and the same coordinate system is established for the initial image and the upper test image. The initial image and the upper test image are mapped to coordinates, and the initial area of ​​each pin is compared with the upper test area. If the initial area is smaller than the upper test area, it indicates that the corresponding pin may be protruding outward from the package body, and it is marked as unqualified; if the initial area is greater than or equal to the upper test area, it indicates that the root of the corresponding pin is stable and no outward extension has occurred, so the pin with an initial area greater than or equal to the upper test area is selected as the initial selected pin.

[0051] S324, obtain the intersection area of ​​the initial contour of the initial selection pin and the upper test contour as the initial selection area, determine the area of ​​the initial selection area as the initial selection area, compare the initial selection area with the preset standard area range, and extract the initial selection pins whose initial selection area is within the standard area range as the first intermediate result.

[0052] It should be noted that although step S323 removes the leads extruded from the package body, the initial selected leads may contain cases of excessive bending. In the case of excessive bending, although the upper test area corresponding to the initial selected lead does not increase, its spatial position of contour is severely offset and no longer coincides with the initial contour. Therefore, only when the contour after compression highly coincides with the initial contour (i.e., the area of ​​the intersection region is large) can it be said that the initial selected lead has only undergone normal micro-elastic deformation; conversely, if the area of ​​the intersection region is too small, it indicates that the initial selected lead has undergone abnormal deformation, which is due to material fatigue or insufficient strength.

[0053] It is understandable that, such as Figure 3 As shown, the intersection area of ​​the initial contour of the preliminary selection pin and the upper test contour is extracted as the preliminary selection area, and the area of ​​the preliminary selection area is calculated as the preliminary selection area. The preliminary selection area is compared with the preset standard area range. If the preliminary selection area is within the preset standard area range, it means that the corresponding preliminary selection pin has only undergone a qualified minor deformation and is included in the first intermediate result; if the preliminary selection area exceeds the preset standard area range, it means that the corresponding preliminary selection pin is excessively bent or has a serious positional offset and is marked as unqualified.

[0054] The standard area range refers to the reasonable range of the initial area of ​​a qualified VDMOS pin after it has been squeezed in the vertical direction, which is determined in advance through a large number of experiments. It is usually set as a percentage of the initial area, such as 85%-100% of the initial area.

[0055] S33, select a second pressure head based on the first intermediate result, and use the second pressure head to press the pin corresponding to the first intermediate result upward based on the preset detection point and preset pressure to obtain the first detection result.

[0056] It should be noted that after the upper test group completes the test, in this embodiment, the lower test group is called to continue to push the initial selected pins corresponding to the first intermediate result upward, and the qualified pins that have passed the test of the lower test group are selected as the first detection result.

[0057] The second pressure head refers to the pressure head selected from the lower test group, whose number is exactly the same as the number of the initial selected pins corresponding to the first intermediate result.

[0058] In some embodiments, step S33 (selecting a second pressure head based on the first intermediate result, and using the second pressure head to press the pin corresponding to the first intermediate result upward based on a preset detection point and a preset pressure to obtain a first detection result) includes S331-S335: S331, obtain the initial selected pin corresponding to the first intermediate result as the first intermediate pin, determine the number of the first intermediate pins as the first intermediate quantity, and select the same number of pressure heads in the next test group as the second pressure heads based on the first intermediate quantity.

[0059] Understandably, the initial selected pin corresponding to the first intermediate result output in step S32 is taken as the first intermediate pin, and the number of the first intermediate pins is counted to obtain the first intermediate quantity. Referring to step S32, based on the first intermediate quantity, an equal number of pressure heads are selected as the second pressure heads to achieve a one-to-one match between the first intermediate pin and the second pressure head.

[0060] S332, according to the preset detection point and preset pressure, calls the second pressure head to squeeze the first intermediate pin upward, and calls the image acquisition device to acquire the lower test image at the end of the squeezing.

[0061] Understandably, the second pressure head presses the first intermediate pin upward according to the preset detection point and preset pressure corresponding to the first intermediate pin, and maintains the pressure state at the end of the pressing and acquires the test image.

[0062] The lower test image refers to the top-view image of the VDMOS under test taken by the image acquisition device when the second pressure head completes the upward extrusion.

[0063] S333: Extract the contours of each first intermediate pin based on the lower test image as the lower test contour, and obtain the area of ​​the lower test contour as the lower test area.

[0064] It is easy to understand that, referring to steps S321 and S322, the lower test image is processed, the contours of each first intermediate pin in the lower test image are extracted as the lower test contours, and their areas are calculated as the lower test areas.

[0065] Among them, the lower test profile refers to the profile of a single first intermediate pin obtained based on the lower test image, and the lower test area refers to the actual area corresponding to the pixel region enclosed by the lower test profile.

[0066] S334 maps the initial image onto the lower test image, compares the initial area of ​​the first intermediate pin with the lower test area, and selects the first intermediate pin whose initial area is greater than or equal to the lower test area as the reselected pin.

[0067] It is understandable that both the initial image and the next test image are acquired by an image acquisition device, therefore the image sizes of the initial image and the next test image are the same, and the same coordinate system is established for the initial image and the next test image. The initial image and the next test image are mapped to coordinates, and the initial area of ​​each first intermediate pin is compared with the area of ​​the next test. If the initial area is smaller than the area of ​​the next test, it indicates that the corresponding first intermediate pin may be extended outward from the package body, and is marked as unqualified; if the initial area is greater than or equal to the area of ​​the next test, it indicates that the root of the corresponding first intermediate pin is stable and no outward extension has occurred, so the first intermediate pin with an initial area greater than or equal to the area of ​​the next test is selected as the reselected pin.

[0068] S335, obtain the intersection area of ​​the initial contour of the reselected pin and the lower test contour as the reselected area, determine the area of ​​the reselected area as the reselected area, compare the reselected area with the preset standard area range, and extract the reselected pins whose reselected area is within the standard area range as the first detection result.

[0069] Understandably, the intersection of the initial contour of the reselected pin and the lower test contour is extracted as the reselection area, and the area of ​​the reselection area is calculated as the reselection area. The reselection area is compared with a preset standard area range. If the reselection area is within the preset standard area range, it indicates that the corresponding reselected pin has only undergone a minor deformation that is acceptable, and it is included in the first test result; if the reselection area exceeds the preset standard area range, it indicates that the corresponding reselected pin is excessively bent or has a serious positional offset, and it is marked as unacceptable.

[0070] S4. Based on the first detection result, preset detection points and preset pressure, the pressure head in the left and right test groups is called to perform left and right squeezing tests on the first detection pin of the VDMOS under test, and the second detection result is obtained.

[0071] It should be noted that in practical use, VDMOS devices are subjected to not only vertical stress but also horizontal shear force or torque, such as during pin bending or PCB thermal expansion and contraction. While step S3 verified the pin's resistance to compression and tension in the vertical direction, it could not detect the pin's stability in the horizontal direction. For example, some pins may be vertically robust, but defects in the root molding compound's lateral restraint could cause overall translation or lateral deformation when subjected to lateral pressure. This embodiment utilizes left and right test groups to perform horizontal physical tests on the selected pins corresponding to the first test results, thereby determining the final qualified pins.

[0072] The left and right squeeze test refers to the process of first squeezing the pin to the right with the left pressure head, and then squeezing the pin to the left with the right pressure head. The second test result refers to the set of pins that are deemed qualified after being tested by the upper and lower test group and the left and right test group.

[0073] In some embodiments, step S4 (calling the pressure head in the left and right test groups to perform left and right squeezing tests on the first detection pin of the VDMOS under test according to the first detection result, the preset detection point and the preset pressure, to obtain the second detection result) includes S41-S44: S41, the left and right test groups include a left test group and a right test group, and the left pressure head arranged in sequence in the left test group and the right pressure head arranged in sequence in the right test group are obtained.

[0074] It is understood that the left and right test groups of the present invention include a left test group for applying pressure to the right and a right test group for applying pressure to the left, and the left test group includes a plurality of left pressure heads arranged in sequence, and the right test group includes a plurality of right pressure heads arranged in sequence.

[0075] The left test group refers to the sub-unit responsible for applying rightward squeezing force within the left and right test groups. It consists of multiple left pressure heads arranged sequentially at preset intervals. The left test group can carry the left pressure heads into the gap between the pins and drive the left pressure heads to move horizontally to the right to apply pressure to the pins. The right test group refers to the sub-unit responsible for applying leftward squeezing force within the left and right test groups. It consists of multiple right pressure heads arranged sequentially at preset intervals. The right test group can carry the right pressure heads into the gap between the pins and drive the right pressure heads to move horizontally to the left to apply pressure to the pins. The left pressure head refers to the pressure head in the left test group, and the right pressure head refers to the pressure head in the right test group. The left and right pressure heads can not only perform horizontal pressure movement but also vertical position movement. The vertical position movement is for position adjustment according to preset detection points.

[0076] S42, obtain the reselected pin corresponding to the first detection result as the first detection pin, and determine the number of the first detection pins as the first detection quantity.

[0077] It is easy to understand that the reselection pin corresponding to the first detection result is taken as the first detection pin, and the number of the first detection pins is counted as the first detection quantity.

[0078] S43, based on the first detection quantity, select an equal number of left pressure heads in the left test group as the third pressure heads, call the third pressure heads to squeeze the first detection pin to the right according to the preset detection point and preset pressure, and call the image acquisition device to acquire the left test image at the end of the squeezing, compare the left test image with the initial image to obtain the second intermediate result.

[0079] It should be noted that this embodiment is the first stage of the left and right compression test (compression to the right), which identifies whether the pin shifts laterally or deforms excessively when subjected to horizontal force. Specifically, if the pin root is loose, the pin may shift laterally when subjected to horizontal pressure. In a top-down view, this shift manifests as the entire pin moving horizontally relative to the package body. If the pin material is not strong enough, it will bend significantly to the right under pressure, directly exceeding the preset conditions.

[0080] It is understandable that, such as Figure 4 As shown, based on the first detection quantity, an equal number of left pressure heads are selected as the third pressure heads to achieve a one-to-one match between the first detection pin and the third pressure head. Combined with preset detection points and preset pressure, the third pressure head is driven to squeeze the first detection pin to the right. At the end of the squeezing, the pressure is maintained and a left test image is acquired. The left test image is compared with the initial image, and the first detection pin with qualified deformation is selected as the second intermediate result.

[0081] The left test image refers to the top view image of the VDMOS under test taken by the image acquisition device when the third pressure head completes the rightward extrusion; the second intermediate result refers to the set of pins that have passed the deformation test by comparing the left test image with the initial image.

[0082] In some embodiments, step S43 (comparing the left test image and the initial image to obtain a second intermediate result) includes S431-S434: S431, extract the contours of each first detection pin as the left test contour based on the left test image.

[0083] It is easy to understand that, referring to step S321, the left test image is processed, and an edge detection operator (such as Canny or Sobel) is used to identify the edge of the first detection pin to generate a closed left test profile.

[0084] The left test profile refers to the profile of a single first detection pin obtained based on the left test image.

[0085] S432, obtain the boundary line on the left test contour that overlaps with the package body as the left test boundary, and extract the boundary line on the initial contour that overlaps with the package body as the initial boundary.

[0086] It should be noted that to determine whether the pin has undergone overall lateral movement, the key is to observe whether the boundary where the pin overlaps with the package body has moved. It is normal for the tip of the pin to undergo elastic deformation under force, but the boundary where the pin overlaps with the package body should remain completely still. In this embodiment, the boundary line at the junction of the first detection pin and the package body is extracted as a reference line for determining whether the root of the first detection pin is loose.

[0087] It is understandable that the boundary line that overlaps with the package body is extracted from the left test contour as the left test boundary, and similarly, the boundary line that overlaps with the package body is extracted from the initial contour as the initial boundary.

[0088] The encapsulation body refers to the solid insulating shell used to wrap and protect the internal semiconductor wafers and bonding wires in a VDMOS device.

[0089] S433, map the initial image onto the left test image, and select the left test contour corresponding to the left test boundary that coincides with the initial boundary as the initial screening contour.

[0090] It should be noted that if the first detection pin is merely bent, its left test boundary should coincide with the initial boundary; if the first detection pin is loose at the root, causing overall translation, then there will be a significant misalignment or gap between the left test boundary and the initial boundary.

[0091] It is understandable that both the initial image and the left test image are acquired by an image acquisition device, therefore their image sizes are the same. The same coordinate system is established for both images, and coordinate mapping is performed between them. After the initial image is mapped onto the left test image, the left test boundary of each first detection pin is compared with the initial boundary. If the left test boundary of the first detection pin does not coincide with the initial boundary, it indicates that the corresponding first detection pin has shifted laterally and is marked as unqualified. If the left test boundary of the first detection pin coincides with the initial boundary, it indicates that the root of the corresponding first detection pin is well fixed, and the left test contour corresponding to the left test boundary that coincides with the initial boundary is directly selected as the initial screening contour.

[0092] S434, obtain the area of ​​the intersection region of the initial screening contour and the corresponding initial contour as the initial screening area, compare the initial screening area with the preset approved area range, and extract the first detection pin whose initial screening area is within the approved area range as the second intermediate result.

[0093] It should be noted that the pin corresponding to the initial screening profile only indicates that the root is not loose, not that there is no deformation. If the pin material is too soft, under horizontal pressure, although the root remains stationary, the upper part of the pin will bend significantly. This excessive deformation will cause the intersection area between the pin's profile after being subjected to force (initial screening profile) and the initial profile to become smaller. Only when the area of ​​the intersection area is large enough can it be said that the pin's lateral bending amplitude is within the allowable elastic range; if the area of ​​the intersection area is too small, it indicates that excessive elastic deformation has occurred.

[0094] Understandably, the intersection area of ​​the initial screening profile and the corresponding initial profile is extracted, and the area of ​​this intersection area is calculated as the initial screening area. The initial screening area is compared with a preset approved area range. If the initial screening area is within the preset approved area range, it indicates that the corresponding first detection pin has only undergone a qualified minor deformation and is included in the second intermediate result; if the initial screening area exceeds the preset approved area range, it indicates that the corresponding first detection pin is excessively bent and is marked as unqualified.

[0095] The approved area range refers to the reasonable range of the initial screening area after the qualified VDMOS pins are squeezed in the horizontal direction, which is determined in advance through a large number of experiments. It is usually set as a percentage of the initial area, such as 80%-100% of the initial area (similar to the initial screening area accounting for 80%-100% of the initial area).

[0096] S44, select the right pressure head according to the second intermediate result to obtain the fourth pressure head, and call the fourth pressure head to squeeze the first detection pin corresponding to the second intermediate result to the left based on the preset detection point and preset pressure to obtain the second detection result.

[0097] It should be noted that the lateral stability of the pins may also have directional differences. Therefore, after the left test group has completed the test, in this embodiment, the right test group is called to continue to squeeze the first detection pin (i.e., the second intermediate pin) corresponding to the second intermediate result to the left, and the qualified second intermediate pin that has passed the test of the right test group is selected as the first detection result.

[0098] The fourth pressure head refers to the right pressure head selected from the right test group, which has the same number of first detection pins as the second intermediate result.

[0099] In some embodiments, step S44 (selecting the right pressure head to obtain the fourth pressure head based on the second intermediate result, and calling the fourth pressure head to press the first detection pin corresponding to the second intermediate result to the left based on the preset detection point and preset pressure to obtain the second detection result) includes S441-S445: S441, obtain the first detection pin corresponding to the second intermediate result as the second intermediate pin, determine the number of the second intermediate pins as the second intermediate quantity, and select an equal number of right pressure heads in the right test group as the fourth pressure head based on the second intermediate quantity.

[0100] Understandably, the first detection pin corresponding to the second intermediate result is taken as the second intermediate pin, and the number of the second intermediate pins is counted to obtain the second intermediate quantity. Based on the second intermediate quantity, an equal number of right pressure heads are selected as the fourth pressure head to achieve a one-to-one match between the second intermediate pin and the fourth pressure head.

[0101] S442, according to the preset detection point and preset pressure, calls the fourth pressure head to squeeze the second middle pin to the left, and calls the image acquisition device to acquire the right test image at the end of the squeezing.

[0102] Understandably, the fourth pressure head presses the second intermediate pin to the left according to the preset detection point and preset pressure corresponding to the second intermediate pin, and maintains the pressure state at the end of the pressing and acquires the right test image.

[0103] The right test image refers to the top-view image of the VDMOS under test taken by the image acquisition device when the fourth pressure head completes the leftward compression.

[0104] S443, extract the contours of each second intermediate pin from the right test image as the right test contour, and obtain the boundary line on the right test contour that overlaps with the package body as the right test boundary.

[0105] It is easy to understand that, referring to step S321, the right test image is processed, and the edge detection operator (such as Canny or Sobel) is used to identify the edge of the second middle pin, generate a closed right test profile, and extract the boundary line that overlaps with the package body from the right test profile as the right test boundary.

[0106] The right test profile refers to the profile of a single second intermediate pin obtained based on the right test image.

[0107] S444, map the initial image onto the right test image, and select the right test contour corresponding to the right test boundary that coincides with the initial boundary as the rescreening contour.

[0108] It is understandable that both the initial image and the right test image are acquired by an image acquisition device, therefore their image sizes are identical. The same coordinate system is established for both images, and coordinate mapping is performed between them. After the initial image is mapped onto the right test image, the right test boundary of each second intermediate pin is compared with the initial boundary. If the right test boundary of the second intermediate pin does not coincide with the initial boundary, it indicates that the corresponding second intermediate pin has shifted laterally and is marked as unqualified. If the right test boundary of the second intermediate pin coincides with the initial boundary, it indicates that the root of the corresponding second intermediate pin is well fixed, and the right test contour corresponding to the right test boundary that coincides with the initial boundary is directly selected as the re-screening contour.

[0109] S445, obtain the area of ​​the intersection region of the rescreening contour and the corresponding initial contour as the rescreening area, compare the rescreening area with the preset approved area range, and extract the second intermediate pin that is within the approved area range as the second detection result.

[0110] Understandably, the intersection area of ​​the re-screening contour and the corresponding initial contour is extracted, and the area of ​​this intersection area is calculated as the re-screening area. The re-screening area is compared with a preset approved area range. If the re-screening area is within the preset approved area range, it indicates that the corresponding second intermediate pin has only undergone a qualified minor deformation, and it is included in the second test result; if the re-screening area exceeds the preset approved area range, it indicates that the corresponding second intermediate pin is excessively bent laterally, and it is marked as unqualified.

[0111] In some embodiments, S51-S55 are also included: S51, based on the pressure monitoring device, continuously monitors the pressure value of the indenter performing the extrusion test in the left and right test groups.

[0112] It should be noted that during the left and right compression test, the indenter in the left and right test groups is inserted into the narrow gap between the pins to push laterally. Since the pin surface is usually smooth and arc-shaped, if the indenter does not penetrate deeply enough or the contact angle is not good, slippage can easily occur during the application of force, that is, the indenter slips off the side of the pin. Once slippage occurs, the test data will be invalid.

[0113] It is understood that in this embodiment, during the entire process of performing left and right compression tests in the left and right test groups, the pressure value of the compression heads (third compression head and fourth compression head) being compressed is continuously monitored by a pressure monitoring device.

[0114] Among them, the pressure monitoring device refers to the hardware device used to continuously and accurately monitor the real-time pressure value of the indenter that performs the extrusion test in the left and right test groups. It can be integrated with the indenter, such as by building a miniature pressure sensor in the end of the indenter, or by collecting pressure feedback from the relevant drive mechanism of the indenter through a pressure transmitter.

[0115] S52, when it is determined that there is a pressure head with a pressure value of zero, the corresponding pressure head is obtained as the selected pressure head, and the maximum pressure of the selected pressure head for performing the extrusion test is retrieved based on the pressure monitoring device as the critical pressure.

[0116] It should be noted that in a normal compression test, the pressure value should increase linearly with the compression time until the preset pressure is reached. If the pressure value suddenly drops sharply to zero before the test is over, it indicates that the indenter has slipped and moved to the other side.

[0117] Understandably, when the pressure monitoring device detects that the pressure value of a certain pressure head suddenly drops to 0 before reaching the preset pressure (e.g., 1N), it immediately locks that pressure head as the selected pressure head (a number can be assigned to the pressure head). Subsequently, it retrieves the pressure record of the selected pressure head before the zeroing moment and extracts the maximum pressure of the selected pressure head for performing the extrusion test as the critical pressure, for example, 0.8N.

[0118] Among them, the selected pressure head refers to the pressure head whose pressure value suddenly drops to zero during the left and right compression test, that is, the pressure head that has slipped and failed; the critical pressure refers to the maximum pressure value recorded by the pressure monitoring device before the selected pressure head drops to zero.

[0119] S53. Based on the difference between the preset pressure and the critical pressure, the critical difference is obtained, and the ratio of the critical difference to the preset pressure is calculated to obtain the pressure ratio.

[0120] It is easy to understand that the difference between the preset pressure and the critical pressure is calculated to obtain the critical difference, and the ratio of the critical difference to the preset pressure is calculated to obtain the pressure ratio. The larger the pressure ratio, the earlier the pressure head slippage occurs, and the greater the subsequent extension compensation of the pressure head is required.

[0121] S54, obtain the length of the pressure head in the left and right test groups as the initial length, and obtain the extension length based on the product of the initial length and the pressure ratio.

[0122] It is easy to understand that the length of the pressure head in the left and right test groups is taken as the initial length, and the extension length is calculated by multiplying the initial length by the pressure ratio.

[0123] The initial length refers to the original effective length of the indenter in the left and right test groups, while the extension length refers to the additional distance increment that the selected indenter needs to extend to prevent slippage again.

[0124] S55, the selected pressure head is extended based on the extension length.

[0125] Understandably, based on the calculated extension length, the selected pressure head is mechanically extended, or the length is directly extended by structural adjustment, thereby increasing the effective length of the selected pressure head extending into the pin gap.

[0126] In addition, after the selected pressure head is extended, the selected pressure head is called again to perform a compression test on the corresponding pin to ensure that the adjusted selected pressure head can stably apply the preset pressure and complete the test of the corresponding pin.

[0127] See Figure 5 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present invention. The electronic device 40 includes: a processor 41, a memory 42, and a computer program; wherein... The memory 42 is used to store the computer program, and the memory may also be flash memory. The computer program is, for example, an application program or functional module that implements the above method.

[0128] The processor 41 is configured to execute the computer program stored in the memory to implement the various steps performed by the device in the above method. For details, please refer to the relevant descriptions in the preceding method embodiments.

[0129] Alternatively, the memory 42 can be either standalone or integrated with the processor 41.

[0130] When the memory 42 is a device independent of the processor 41, the device may further include: Bus 43 is used to connect the memory 42 and the processor 41.

[0131] The present invention also provides a readable storage medium storing a computer program, which, when executed by a processor, is used to implement the methods provided in the various embodiments described above.

[0132] The readable storage medium can be a computer storage medium or a communication medium. A communication medium includes any medium that facilitates the transfer of computer programs from one location to another. A computer storage medium can be any available medium accessible to a general-purpose or special-purpose computer. For example, a readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application-Specific Integrated Circuit (ASIC). Alternatively, the ASIC can be located in a user equipment. Of course, the processor and the readable storage medium can also exist as discrete components in a communication device. The readable storage medium can be a read-only memory (ROM), random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0133] The present invention also provides a program product including executable instructions stored in a readable storage medium. At least one processor of the device can read the executable instructions from the readable storage medium, and the at least one processor executes the executable instructions to cause the device to implement the methods provided in the various embodiments described above.

[0134] In the embodiments of the above-described device, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly manifested as execution by a hardware processor, or execution by a combination of hardware and software modules within the processor.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for manufacturing a VDMOS, characterized in that, include: An initial image of the VDMOS under test is acquired using an image acquisition device, and the device model and pin count of the VDMOS under test are determined based on the initial image. According to the device model, obtain the preset detection points on each pin, and based on the preset detection points, obtain the preset pressure corresponding to the pressure head in the upper and lower test groups and the left and right test groups from the preset point pressure reference table; Based on the number of pins, preset detection points, and preset pressure, the pressure head in the upper and lower test group is controlled to perform an upper and lower squeezing test on the pins of the VDMOS under test, and the first detection result is obtained. Based on the first test result, preset test points, and preset pressure, the pressure head in the left and right test groups is called to perform left and right squeezing tests on the first test pin of the VDMOS under test, and the second test result is obtained.

2. The method according to claim 1, characterized in that, The pressure head in the upper and lower test group, based on the number of pins, preset detection points, and preset pressure, performs an upper and lower compression test on the pins of the VDMOS under test to obtain a first detection result, including: The upper and lower test groups include an upper test group and a lower test group, and the upper pressure head arranged in sequence in the upper test group and the lower pressure head arranged in sequence in the lower test group are obtained; Based on the number of pins, select an equal number of upper pressure heads as the first pressure heads in the upper test group. According to the preset detection points and preset pressure, call the first pressure heads to press the pins downwards, and call the image acquisition device to acquire the upper test image at the end of the pressing. Compare the upper test image with the initial image to obtain the first intermediate result. Based on the first intermediate result, a second pressure head is selected. Based on the preset detection point and preset pressure, the second pressure head is used to press the pin corresponding to the first intermediate result upward to obtain the first detection result.

3. The method according to claim 2, characterized in that, The comparison between the test image and the initial image yields a first intermediate result, including: The contours of each pin are extracted from the initial image as the initial contours, and the area of ​​the initial contours is obtained as the initial area. Extract the contours of each pin from the above test image as the above test contour, and obtain the area of ​​the above test contour as the above test area. Map the initial image onto the upper test image, compare the initial area of ​​each pin with the upper test area, and select the pins whose initial area is greater than or equal to the upper test area as the initial selection pins. The intersection area of ​​the initial contour of the initial selected pin and the upper test contour is obtained as the initial selection area. The area of ​​the initial selection area is determined as the initial selection area. The initial selection area is compared with the preset standard area range, and the initial selected pins whose initial selection area is within the standard area range are extracted as the first intermediate result.

4. The method according to claim 3, characterized in that, The first intermediate result selects a second pressure head. Based on a preset detection point and a preset pressure, the second pressure head is used to press the pin corresponding to the first intermediate result upwards to obtain a first detection result, including: The initial pins corresponding to the first intermediate results are obtained as the first intermediate pins. The number of the first intermediate pins is determined as the first intermediate number. Based on the first intermediate number, an equal number of pressure heads are selected in the next test group as the second pressure heads. According to the preset detection points and preset pressure, the second pressure head is called to squeeze the first intermediate pin upward, and the image acquisition device is called to acquire the lower test image at the end of the squeezing. Based on the lower test image, the contour of each first intermediate pin is extracted as the lower test contour, and the area of ​​the lower test contour is obtained as the lower test area. The initial image is mapped onto the next test image. The initial area of ​​the first intermediate pin and the area of ​​the next test are compared. The first intermediate pin with an initial area greater than or equal to the area of ​​the next test is selected as the next selected pin. The intersection of the initial contour and the lower test contour of the reselected pin is obtained as the reselected region. The area of ​​the reselected region is determined as the reselected area. The reselected area is compared with the preset standard area range. The reselected pins whose reselected area is within the standard area range are extracted as the first detection result.

5. The method according to claim 4, characterized in that, The process involves calling the pressure head in the left and right test groups to perform a left and right compression test on the first detection pin of the VDMOS under test based on the first detection result, preset detection points, and preset pressure, to obtain a second detection result, including: The left and right test groups include a left test group and a right test group, and the left pressure head arranged in sequence in the left test group and the right pressure head arranged in sequence in the right test group are obtained; The reselected pin corresponding to the first detection result is used as the first detection pin, and the number of the first detection pins is determined as the first detection quantity. Based on the first detection quantity, select an equal number of left pressure heads in the left test group as the third pressure heads. According to the preset detection point and preset pressure, call the third pressure head to squeeze the first detection pin to the right, and call the image acquisition device to acquire the left test image at the end of the squeezing. Compare the left test image with the initial image to obtain the second intermediate result. Based on the second intermediate result, the right pressure head is selected to obtain the fourth pressure head. Based on the preset detection point and preset pressure, the fourth pressure head is called to squeeze the first detection pin corresponding to the second intermediate result to the left to obtain the second detection result.

6. The method according to claim 5, characterized in that, The comparison between the left test image and the initial image yields a second intermediate result, including: The contours of each first detection pin are extracted from the left test image as the left test contours; Obtain the boundary line on the left test contour that overlaps with the package body as the left test boundary, and extract the boundary line on the initial contour that overlaps with the package body as the initial boundary. The initial image is mapped onto the left test image, and the left test contour corresponding to the left test boundary that coincides with the initial boundary is selected as the initial screening contour. The area of ​​the intersection region between the initial screening profile and the corresponding initial profile is obtained as the initial screening area. The initial screening area is compared with the preset approved area range, and the first detection pin whose initial screening area is within the approved area range is extracted as the second intermediate result.

7. The method according to claim 6, characterized in that, The process involves selecting a fourth pressure head based on the second intermediate result, and then, based on a preset detection point and a preset pressure, using the fourth pressure head to press the first detection pin corresponding to the second intermediate result to the left to obtain a second detection result, including: The first detection pin corresponding to the second intermediate result is obtained as the second intermediate pin, the number of the second intermediate pins is determined as the second intermediate number, and based on the second intermediate number, an equal number of right pressure heads are selected in the right test group as the fourth pressure head. According to the preset detection points and preset pressure, the fourth pressure head is called to squeeze the second middle pin to the left, and the image acquisition device is called to acquire the right test image at the end of the squeezing. The contours of each second intermediate pin are extracted from the right test image as the right test contours, and the boundary lines that overlap with the package body on the right test contours are obtained as the right test boundaries. Map the initial image onto the right test image, and select the right test contour corresponding to the right test boundary that coincides with the initial boundary as the rescreening contour; The area of ​​the intersection region between the rescreening contour and the corresponding initial contour is obtained as the rescreening area. The rescreening area is compared with the preset approved area range, and the second intermediate pin that is within the approved area range is extracted as the second detection result.

8. The method according to claim 1, characterized in that, Also includes: The pressure value of the indenter performing the extrusion test in the left and right test groups is continuously monitored by the pressure monitoring device. When it is determined that there is a pressure head with a pressure value of zero, the corresponding pressure head is obtained as the selected pressure head, and the maximum pressure of the selected pressure head for performing the extrusion test is retrieved based on the pressure monitoring device as the critical pressure; The critical difference is obtained by calculating the ratio of the critical difference to the preset pressure and the critical pressure. The length of the pressure head in the left and right test groups is used as the initial length. The extension length is obtained by multiplying the initial length by the pressure ratio. The selected pressure head is extended based on the stated extension length.

9. An electronic device, characterized in that, include: The method comprises a memory, a processor, and a computer program, the computer program being stored in the memory, and the processor executing the computer program to perform the method according to any one of claims 1 to 8.

10. A storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, is used to implement the method described in any one of claims 1 to 8.

Images