Chip coplanarity detection device and method

Abstract

The invention provides a chip coplanarity detection device. The chip coplanarity detection device comprises a linear driving mechanism, a laser scanning head and a detection table, the linear driving mechanism comprises a movable part and a driving part, and the driving part is used for driving the movable part to do linear reciprocating motion along a preset motion track. The laser scanning head is fixedly connected with the movable part, and when the driving part drives the movable part to move, the movable part drives the laser scanning head to do linear reciprocating motion along a preset motion track. The detection table top is used for placing a to-be-detected chip, and the detection plane of the laser scanning head coincides with the side, close to the to-be-detected chip, of the detection table top. The linear driving mechanism is arranged to drive the laser scanning head to move along the straight line, and the chip to be detected is placed on the independent detection table board for detection, so that the chip to be detected is prevented from moving, and the detection precision is improved.

Description

Technical Field

[0001] This application relates to the technical field, and particularly to a chip coplanarity detection device. Background Art

[0002] The coplanarity of components refers to the relative height difference of the leads of components on the same plane, and this height difference directly affects the performance of the circuit. If the height difference of the leads of components is too large, it will affect the transmission of circuit signals and cause the circuit to work unstably. Therefore, during the component screening process, it is necessary to check the coplanarity of components to ensure that the circuit performance meets the requirements.

[0003] With the rapid development of microelectronics technology, the integrated circuit manufacturing process has also been continuously improved. In recent years, there has been a qualitative leap in integrated circuits in China. Integrated circuit products have gradually matured and gradually formed a mass production capacity, and the demand for screening tests has increased day by day. However, most domestic component screening units have less research on the coplanarity detection of component appearance. Usually, the coplanarity detection is carried out by directly observing with the naked eye, and the detection results of this method have large errors and are prone to misjudgment. Summary of the Invention

[0004] Based on the above purpose, this application provides a chip coplanarity detection device, including: a linear drive mechanism, a laser scanning head, and a detection table. The linear drive mechanism includes a movable part and a drive part, and the drive part is used to drive the movable part to perform a linear reciprocating motion along a preset movable trajectory. The laser scanning head is fixedly connected to the movable part. When the drive part drives the movable part to move, the movable part drives the laser scanning head to perform a linear reciprocating motion along the preset movable trajectory. The detection table is used to place the chip to be detected, and the detection plane of the laser scanning head coincides with the side of the detection table close to the chip to be detected.

[0005] In some embodiments, the chip coplanarity detection device further includes a housing. The housing includes a base, an outer shell, and a top cover. The outer shell is fixedly connected to the upper surface of the base, and the lower surface of the top cover is fixedly connected to one end of the outer shell away from the base. The linear drive mechanism is fixedly connected to the base, and the linear drive mechanism and the laser scanning head are arranged inside the outer shell. The top cover further includes a first mounting hole, and the detection table is arranged in the first mounting hole.

[0006] In some embodiments, the outer shell further includes a second mounting hole. The laser scanning head further includes a control cable, and the control cable passes through the second mounting hole and is connected to the controller.

[0007] In some embodiments, the chip coplanarity detection device further includes a rolling device. The rolling device is annular, the outer ring of the rolling device is fixedly connected to the second mounting hole, the inner ring of the rolling device abuts against the control cable, and the outer ring and the inner ring are rotatably connected.

[0008] In some embodiments, the laser scanning head is configured to: in response to a control signal output by the controller, the scanning surface of the laser scanning head performs at least two scans on the chip to be detected, and coplanarity detection is performed on the chip to be detected based on at least two scanned images.

[0009] In some embodiments, the linear drive mechanism further includes a guide rail, the movable part is arranged on the guide rail, and the driving part is arranged at one end of the guide rail. The linear drive mechanism is configured to: in response to a control signal output by the controller, the driving part drives the movable part to move from the first end of the guide rail to the second end of the guide rail, and then move from the second end of the guide rail to the first end of the guide rail.

[0010] In some embodiments, the chip coplanarity detection device further includes a fixing fixture for fixing the chip to be detected on the upper surface of the detection table.

[0011] This application also provides a method for detecting chip coplanarity, including: scanning the surface of the chip to be detected to obtain a scanned dot matrix, and generating a first height map based on the scanned dot matrix. Calculating the relative heights of at least four pins of the chip to be detected according to the first height map. Calculating the height difference of the pins according to the relative heights, and if the height difference meets a preset error threshold, the chip to be detected is a qualified product.

[0012] In some embodiments, calculating the relative heights of at least four pins of the chip to be detected according to the first height map specifically includes: identifying the first height map to obtain a chip surface image and a chip pin image. Constructing a reference plane based on the chip surface image, and establishing a space rectangular coordinate system based on the reference plane. Calculating the spatial coordinates of at least four pins according to the space rectangular coordinate system and the chip pin image. Calculating the relative heights according to the spatial coordinates.

[0013] In some embodiments, scanning the surface of the chip to be detected to obtain a scanned dot matrix and generating a first height map based on the scanned dot matrix specifically includes: performing at least two scans on the chip to be detected, aligning at least two groups of scanned dot matrices to obtain a composite dot matrix. Denoising the composite dot matrix to obtain a first height map.

[0014] As can be seen from the above, the chip coplanarity detection device provided by this application drives the laser scanning head to move linearly by setting a linear drive mechanism, and places the chip to be detected on an independent detection table for detection, thereby preventing the chip to be detected from moving and improving the detection accuracy. Description of the Drawings

[0015] To more clearly illustrate the technical solutions in the present application or related technologies, the following will briefly introduce the drawings required for use in the embodiments or related technology descriptions. Obviously, the drawings in the following descriptions are only the embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0016] Figure 1 Schematic structural diagram of the chip coplanarity detection device provided by the embodiment of the present application from the first perspective;

[0017] Figure 2 Schematic structural diagram of the chip coplanarity detection device provided by the embodiment of the present application from the second perspective;

[0018] Figure 3 Schematic flow diagram of the chip coplanarity detection method provided by the embodiment of the present application;

[0019] Figure 4 Schematic flow diagram of the method for calculating the relative height of pins provided by the embodiment of the present application;

[0020] Figure 5 Schematic flow diagram of the method for obtaining the first height map provided by the embodiment of the present application;

[0021] Figure 6 Schematic software flow diagram written according to the chip coplanarity detection method provided by the embodiment of the present application.

[0022] Reference numerals: linear drive mechanism - 1; moving part - 11; drive part - 12; guide rail - 13; laser scanning head - 2; detection table - 3; housing - 4; base - 41; outer shell - 42; top cover - 43. Detailed implementation manners

[0023] To make the objectives, technical solutions, and advantages of the present application more clear and understandable, the following further details the present application in combination with specific embodiments and with reference to the accompanying drawings.

[0024] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of this application should have the ordinary meanings understood by those with ordinary skills in the field to which this application belongs. The "first", "second" and similar words used in the embodiments of this application do not denote any order, quantity or importance, but are only used to distinguish different components. Words such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "lower", "left", "right", etc. are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0025] As Figure 1 and Figure 2 shown, this application provides a chip coplanarity detection device, including:

[0026] a linear drive mechanism 1, a laser scanning head 2 and a detection table 3.

[0027] The linear drive mechanism 1 includes a movable part 11 and a drive part 12, and the drive part 12 is used to drive the movable part 11 to perform a linear reciprocating motion along a preset movable trajectory.

[0028] The laser scanning head 2 is fixedly connected to the movable part 11. When the drive part 12 drives the movable part 11 to move, the movable part 11 drives the laser scanning head 2 to perform a linear reciprocating motion along a preset movable trajectory.

[0029] The detection table 3 is used to place the chip to be detected, and the detection plane of the laser scanning head 2 coincides with the side of the detection table 3 close to the chip to be detected.

[0030] In this embodiment, scanning is performed by driving the laser scanning head 2 with the movable part 11 of the linear drive mechanism 1, thereby avoiding jitter of the chip to be measured during the scanning process and affecting the scanning accuracy.

[0031] Place the chip to be detected on the detection table 3, and fix the chip to be detected through the detection table 3 so that the chip to be detected is fixed at a preset scanning position.

[0032] Preferably, the detection table 3 may further include a shock absorption mechanism to prevent the vibration generated by the linear drive mechanism 1 during the scanning process from being transmitted to the chip to be detected.

[0033] As an optional implementation, the laser scanning head can be a 3D laser sensor, using LMI shelf products, with 1920 contour points, X-direction resolution of up to 13-17μm, Z-direction linearity of ±0.01%, and Z-direction repeatability of 0.4μm. The essence of the working principle of the laser sensor is that the laser diode transmitter emits a laser pulse, which is reflected to the receiver diode and records the reflection time from emission to reception. The distance and specific position are obtained by calculating the reflection time and angle. Therefore, this principle can detect the distance of all contour points in a certain surface of the object to be measured (based on the three-dimensional coordinates, the X direction is the width of the measured field of view, and the Z direction is the distance from the sensor receiver to the measured surface). Because the laser diode transmitter has a certain angle with the horizontal plane (a necessary condition for reflection), the scanning field of view is essentially a trapezoid. The specific position can be calculated according to the angle between the laser transmitter and the vertical direction, thereby forming three-dimensional point cloud data, and then the coplanarity result is obtained through image processing.

[0034] As an optional implementation, the linear drive mechanism can adopt a precision screw-type linear motion module with a length of 200mm, positioning reproducibility of ±0.005mm, positioning accuracy of 0.02mm, and parallelism of 0.01mm. The 3D laser sensor is fixed on the module motion platform and driven by a servo motor to drive the 3D laser sensor to move horizontally to perform a scanning action (based on the three-dimensional coordinates, and the Y direction is the module movement direction). The traditional design is that the 3D laser sensor remains stationary, and the object to be measured is placed on the motion module. The object to be measured is in a dynamic state for scanning. In this design, during the movement of the module, the object to be measured is easily displaced due to vibration, thereby causing imaging deformation or phantom, resulting in errors in the detection results. The design in the present invention drives the 3D laser camera to perform linear motion for scanning through the motion module. The object to be measured is completely fixed and remains stationary, and will not cause vibration and displacement. At the same time, because the servo motor drives the linear motion module, it has good smoothness and stability. The scanning during the movement of the 3D laser sensor can also remain stable, avoiding the risk of errors. Since the linear motion module can perform reciprocating linear motion in the Y direction, the present invention uses this feature to perform a second scan on the object to be detected. The motion module moves along the positive direction of the Y axis to the end of the screw rod for the first scan, and then moves back to the starting position along the reverse direction of the Y axis for the second scan, that is, two forward and reverse scans in the Y direction. The two scan results are superimposed to generate an image, thereby reducing the error caused by unidirectional scanning (the effect is more obvious for BGA packaged devices. Since the BGA package lead end is spherical and the laser emitter has a certain emission angle and is not vertical, there will be partial shadows on one side of the scanned image. Taking into account the error of the sensor itself and the positioning accuracy of the motion module, the size of the shadow area of ​​a single scan will affect the detection result. The forward and reverse scans can effectively reduce the shadow area after imaging, thereby making the detection result more accurate).

[0035] In some embodiments, the chip coplanarity detection device further includes a housing 4.

[0036] The housing 4 includes a base 41, an outer shell 42, and a top cover 43. The outer shell 42 is fixedly connected to the upper surface of the base 41, and the lower surface of the top cover 43 is fixedly connected to one end of the outer shell 42 away from the base 41.

[0037] The linear drive mechanism 1 is fixedly connected to the base 41, and the linear drive mechanism 1 and the laser scanning head 2 are disposed inside the outer shell 42.

[0038] The top cover 43 further includes a first mounting hole, and the detection table 3 is disposed in the first mounting hole.

[0039] In this embodiment, by providing the housing 4, multiple structures of the chip coplanarity detection device are integrated into a single module, facilitating the movement of the chip coplanarity detection device.

[0040] Among them, since the pins of the chip to be measured are usually located at the bottom of the chip, in this application, by disposing the linear drive mechanism 1 and the laser scanning head 2 on the base 41, and then disposing the detection table 3 on the top cover 43, when the chip to be measured is being detected, the laser scanning head 2 scans the chip to be measured upward, so that the pins of the chip to be measured are supported by the planar structure of the detection table 3, enabling most of the pins of the chip to be measured to be in the same plane, facilitating subsequent processing of the scanning results.

[0041] In some embodiments, the outer shell 42 further includes a second mounting hole.

[0042] The laser scanning head 2 further includes a control cable, and the control cable passes through the second mounting hole and is connected to the controller.

[0043] In this embodiment, since the amount of data generated by the laser scanning head 2 is large and needs to be transmitted to other devices for processing, by providing a second mounting hole in the outer shell 42 and passing the control cable of the laser scanning head 2 through the second mounting hole to be connected to an independent controller, only the laser scanning head 2, the linear drive device, and part of the control cable are accommodated inside the housing 4, thereby reducing the packaging volume of the chip coplanarity detection device and enabling the chip coplanarity detection device to be applicable to high-density production lines for coplanarity detection of a batch of chips to be measured.

[0044] As an optional implementation, the controller can be controlled by the PLC control system Modbus TCP protocol, and integrated with RS-485 interface communication. Press the detection button, the PLC controller sends a start signal, drives the servo motor to drive the motion module to move linearly along the positive direction of the Y axis, and sends a start scanning signal at the same time, which is transmitted to the 3D laser sensor through the I / O cable. The laser sensor starts scanning, and when the motion platform reaches the end of the positive direction of the Y axis, it sends a signal back to the PLC controller. The PLC controller sends a return signal, and the servo motor reverses to drive the motion platform to move linearly in the opposite direction of the Y axis. During this process, the 3D laser sensor continues to perform scanning operations. When the motion platform returns to the starting point, it sends a signal back to the PLC to reach the starting position. The PLC sends a stop signal, the servo motor stops, and sends a stop scanning signal to the 3D laser sensor. After the 3D laser sensor stops scanning, it performs image processing after two scans in the positive and reverse directions, and transmits the image to the PC screen through the Ethernet interface.

[0045] In some embodiments, the chip coplanarity detection device further includes a rolling device.

[0046] The rolling device is annular, the outer ring of the rolling device is fixedly connected to the second mounting hole, the inner ring of the rolling device abuts against the control cable, and the outer ring is rotatably connected to the inner ring.

[0047] In this embodiment, since the laser scanning head 2 needs to follow the movement of the active end of the linear drive mechanism 1, the control cable will also move relative to the shell 4 when the laser scanning head 2 is scanning. Therefore, in order to avoid damage to the insulating sheath of the control cable, a rolling device is arranged in the second mounting hole to convert the sliding friction between the control cable and the shell 4 into rolling friction, thereby improving the service life of the control cable.

[0048] Preferably, the rolling device is an annular structure with balls embedded inside, the inner ring of the rolling device includes multiple balls, the balls are embedded in the outer ring, and the balls can roll in any direction in the embedded position, the control cable passes through the rolling device and abuts against the balls, when the linear drive mechanism 1 drives the laser scanning head 2 to reciprocate along a preset active trajectory, the laser scanning head 2 drives the control cable to generate rolling friction with the balls.

[0049] In some embodiments, the laser scanning head 2 is configured to: in response to a control signal output by the controller, the scanning surface of the laser scanning head 2 scans the chip to be inspected at least twice, and performs coplanarity inspection on the chip to be inspected based on at least two scanning images.

[0050] In this embodiment, since the coverage of the chip to be tested by the scanning dot matrix of the laser scanning head 2 is low, in order to achieve high-precision scanning of the chip to be tested, scanning the chip to be tested at least twice can improve the accuracy of the scanned image.

[0051] Preferably, in order to achieve precise positioning of at least two scanned images, positioning points may also be provided on the detection table 3. By making the positioning points in at least two scanned images coincide, rapid alignment of the scanned images can be achieved.

[0052] Preferably, at least two scans may also be performed on the chip under test in two directions, thereby increasing the coverage rate of the laser dot matrix on the chip under test.

[0053] More preferably, the detection table 3 may further include a steering device. By rotating the chip under test 180° through the steering device, the laser scanning head 2 can perform scans on the chip under test from two directions by only being driven by the linear drive mechanism 1 to move horizontally.

[0054] More preferably, the laser scanning head 2 may include two scanning surfaces, and two scans of the chip under test can be achieved through one stroke of the linear drive mechanism 1, shortening the scanning time.

[0055] In some embodiments, the linear drive mechanism 1 further includes a guide rail 13. The movable part 11 is arranged on the guide rail 13, and the driving part 12 is arranged at one end of the guide rail 13.

[0056] The linear drive mechanism 1 is configured to: in response to a control signal output by the controller, the driving part 12 drives the movable part 11 to move from the first end of the guide rail 13 to the second end of the guide rail 13, and then move from the second end of the guide rail 13 to the first end of the guide rail 13.

[0057] In this embodiment, by driving the movable part 11 by the driving part 12 to move from the first end of the guide rail 13 to the second end of the guide rail 13, and then move from the second end of the guide rail 13 to the first end of the guide rail 13, and making the laser scanning head 2 perform one scan during both the process of the movable part 11 moving from the first end of the guide rail 13 to the second end of the guide rail 13 and the process of moving from the second end of the guide rail 13 to the first end of the guide rail 13. Since there is a certain tolerance in the stroke of the linear drive mechanism 1 and there are gaps in the scanning dot matrix of the laser scanning head 2, there are certain differences in the two scan results. By superimposing the two scan results, a higher-density scan dot matrix image can be formed.

[0058] In some embodiments, the chip coplanarity detection device further includes a fixed fixture for fixing the chip to be detected on the upper surface of the detection table 3.

[0059] In this embodiment, to ensure that the positions of the scanned images of multiple chips under test are the same, the chips under test can be fixed on the detection table 3 by setting a fixed fixture matching the shape of the chips under test, thereby reducing the recognition time for the coplanarity of the chips under test.

[0060] As an alternative embodiment, the fixed fixture can use a tooling in a hollowed-out form for positioning, including various package sizes such as SOP / SSOP / TSSOP / QFP / BGA, etc. For different package sizes, a single tooling can have 2 - 8 stations, which can effectively increase the number of devices scanned at one time, thereby effectively improving the detection efficiency.

[0061] As can be seen from the above embodiments of the present application, the chip coplanarity detection device provided by the present application drives the laser scanning head 2 to move linearly through the setting of the linear drive mechanism 1, and places the chip to be tested on an independent detection table 3 for detection, thereby preventing the chip to be tested from moving and improving the detection accuracy.

[0062] As Figure 3 shown, the present application also provides a chip coplanarity detection method, including:

[0063] Step S1, scan the surface of the chip to be tested to obtain a scanned dot matrix, and generate a first height map according to the scanned dot matrix.

[0064] Step S2, calculate the relative heights of at least 4 pins of the chip to be tested according to the first height map.

[0065] Step S3, calculate the height difference between the pins according to the relative heights. In response to the height difference meeting a preset error threshold, the chip to be tested is a qualified product.

[0066] In this embodiment, by obtaining the scanned dot matrix on the surface of the chip to be tested and generating a first height map according to the scanned dot matrix, the surface of the chip to be tested can be modeled, and thus the coplanarity of the chip to be tested can be evaluated according to the model.

[0067] By calculating the relative heights of the pins of the chip to be tested and calculating the height difference between the two pins with the largest height difference according to the relative heights, the chip to be tested is screened according to production requirements. When the height difference meets the error threshold provided by the production requirements, the chip is marked as a qualified product and enters the next production process.

[0068] In some embodiments, as Figure 4 shown, wherein, step S2 specifically includes:

[0069] Step S21, identify the first height map to obtain the chip surface image and the chip pin image.

[0070] Step S22, construct a reference plane according to the chip surface image, and establish a space rectangular coordinate system based on the reference plane.

[0071] Step S23, calculate the spatial coordinates of at least 4 pins according to the space rectangular coordinate system and the chip pin image.

[0072] Step S24, calculate the relative height based on the spatial coordinates.

[0073] In some embodiments, as Figure 5 shown, wherein, step S1 specifically includes:

[0074] Step S11, perform at least 2 scans on the chip to be measured, align at least 2 groups of scanned dot matrices to obtain a synthesized dot matrix.

[0075] Step S12, perform noise reduction on the synthesized dot matrix to obtain a first height map.

[0076] As a preferred implementation manner of the present application, the chip coplanarity detection device provided by the present application can be implemented in the following manner:

[0077] By fixing the 3D laser sensor on the slider of the linear motion module, the slider drives the laser sensor to perform reciprocating linear motion, performs 3D scanning on the chips within the field of view, uses an algorithm to convert the obtained 3D image into a 2D image, and then compares it with the standard error value, so as to realize appearance defect recognition and pin coplanarity detection, and the qualified and unqualified images will be differentially marked.

[0078] For the chip coplanarity detection device provided by the present application, it can be operated by the following method:

[0079] Step S10, 3D point cloud acquisition, the 3D laser sensor scans the chips within the field of view, and generates a scanned height / brightness image after obtaining the positions of the silk printing and pins on the chip surface;

[0080] According to the working principle of the laser sensor, the laser diode emitter on the inclined plane emits laser pulses, irradiates the device to be measured in the test area, forms reflections through the device body and the lead-out ends, irradiates the vertical receiver, and the receiver receives the reflected light and records the reflection time from emission to reception. According to the principle of the constancy of the speed of light, through the reflection time and the angle at which the laser is emitted, the distances and positions of all points below the device to be measured to the laser sensor can be obtained, thereby forming three-dimensional point cloud data. The 3D point cloud image function of the sensor can form a 3D image of all the scanned points within the field of view. Since there is a height difference between the lead-out ends of the device to be measured and the plane below the main body, after coloring processing, there will be obvious color differentiation in the 3D image according to the height difference, and the lead-out end area to be detected can be clearly identified, and then the next image processing can be carried out.

[0081] Step S20, image preprocessing, remove the images of the parts other than the chip pins and the surface to prevent interference during the subsequent algorithm operation;

[0082] The image preprocessing step is used to remove the images of the parts other than the device leads and the surface to prevent interference during the subsequent algorithm. Since the components are only welded at the ends of the leads in the final soldering step, only the ends of the leads need to be detected. In the image preprocessing step, through the filtering function, the connection part between the leads and the device body and the shadow parts existing in the image after 3D point cloud acquisition are eliminated, and only the ends of the device leads and the bottom surface of the device body are retained (the significance of retaining the bottom surface of the body is to establish a reference plane based on this plane for matrix transformation). Only the leads and the bottom surface of the body are retained in the preprocessed image.

[0083] Step S30, plane fitting. Based on the XYZ three-dimensional coordinate system, a reference plane is established, and all pin coordinates are determined to obtain the pin coordinate plane.

[0084] In the plane fitting step, based on the XYZ three-dimensional coordinate system, with the bottom surface of the device under test as the reference, a reference plane is established, and all the detected lead coordinates are determined to obtain the coordinates of the leads of the detected device. Since the leads and the device body under test are physically connected, the XY plane coordinate system established with the center of the bottom surface of the body as the origin can map the XY coordinates of each lead. At this time, the Z-axis coordinate of the lead is the coplanarity height to be measured. Color processing is performed on this height coordinate to clearly identify the specific problematic leads.

[0085] Step S40, matrix transformation. Through matrix transformation, the 3D image is converted into a 2D image, plane correction is performed to eliminate the error between the reference plane and the XY plane, the pin coordinates are two-dimensionalized, so that the lead plane is completely in the XY plane, and the height coordinate is retained.

[0086] Step S50, display the image. Color processing is performed on all coordinates, and the image is displayed on the screen.

[0087] The image after matrix transformation can identify the problematic leads either through color difference or position. At the same time, the height coordinate will also be displayed on the right. When the subsequent results are output, this height coordinate will be brought into the set upper and lower limits for comparison and calculation.

[0088] Step S60, result calculation. Calculate the height difference of the pins, output the scanned result and compare it with the preset error value to determine whether the coplanarity of the chip pins is qualified.

[0089] In this application, to achieve the control of the chip coplanarity detection device, this application also provides a control and scan result processing software for the chip coplanarity detection device.

[0090] The application software of the chip coplanarity detection module is designed for the chip pin coplanarity measurement standard in combination with 3D laser vision detection technology. The user interface based on web technology is used for sensor parameter setting and debugging.

[0091] ① 3D laser vision sensor operation function

[0092] The 3D laser vision sensor provides a sensor calibration function, and the sensor can be easily calibrated and perform accurate and stable measurements. The 3D laser vision sensor supports multi-dimensional (2D / 3D) measurement functions, can acquire 3D shape and 2D intensity data and apply various measurement tools to it to achieve powerful detection. Measurement algorithms with preset measurement tools and filtering functions solve application problems. Powerful measurement tools as well as filters, part detection, part matching, part profiling, part segmentation, point cloud trajectory and more tools

[0093] Apply the measurement results to 2D and 3D data, which can be applied to multi-dimensional data, including 3D contours, 3D point clouds and 2D intensity data. 2D and 3D data and measurement results can be generated from one device at the same time. Perform contrast-based detection and conduct advanced 3D shape-based detection on various chip pins.

[0094] ② The software supports multiple communication protocols

[0095] Support all standard industrial protocols to communicate with factory networks and devices for reporting results, diagnosis and monitoring, software upgrade, and exchanging or merging data with other network devices. It can communicate via Ethernet (TCP / IP), and available protocols include Gocator, EtherNet / IP, Modbus, PROFINET, and ASCII, etc.

[0096] ③ Customized human-machine interface design

[0097] Separate design and remote deployment of a customized human-machine interface for remote user operation, setting the sensor, reporting output data to remote users and visualizing the scanned data. It can be deployed on the sensor or industrial control computer and accessed through any computer, touch screen or mobile device connected to the sensor network.

[0098] Among them, the software algorithm process is as Figure 6 shown.

[0099] The 3D laser vision sensor provides a sensor calibration function, and the sensor can be easily calibrated and perform accurate and stable measurements. The 3D laser vision sensor supports multi-dimensional (2D / 3D) measurement functions, can acquire 3D shape and 2D intensity data and apply various measurement tools to them to achieve powerful detection. The measurement algorithm with preset measurement tools and filtering functions solves application problems. Powerful measurement tools and more tools such as filters, part detection, part matching, part profiling, part segmentation, and point cloud trajectory.

[0100] Applying the measurement results to 2D and 3D data, it can be applied to multi-dimensional data, including 3D contours, 3D point clouds, and 2D intensity data. 2D and 3D data and measurement results can be generated simultaneously from one device, and contrast-based detection is performed for advanced detection of various chip pins based on 3D shapes.

[0101] Supports all standard industrial protocols to communicate with factory networks and devices for reporting results, diagnosis and monitoring, software upgrade, and exchanging or merging data with other network devices. It can communicate via Ethernet (TCP / IP), and available protocols include Gocator, EtherNet / IP, Modbus, PROFINET, and ASCII, etc.

[0102] Separate design and remote deployment of a customized human-machine interface for remote user operation, setting the sensor, reporting output data to remote users, and visualizing scan data. It can be deployed on the sensor or industrial control computer and accessed through any computer, touch screen, or mobile device connected to the sensor network.

[0103] Considering that the part of the cable in contact with the housing will cause wear as the camera moves, a circular ring with an arc chamfer is installed at the position where the housing is perforated, and a universal roller screw is installed inside the circular ring, so that the frictional force of the cable during movement is converted from sliding friction to rolling friction, reducing the friction coefficient, thereby reducing external wear of the cable and extending its service life.

[0104] The present invention solves the problem of large result errors caused by coplanarity detection by the human eye, can accurately scan the pins of the device and identify coplanarity, with an accuracy rate of up to 99.9%, a test efficiency of 900 pcs / h, and can greatly improve the appearance detection efficiency, laying a foundation for the automation and intelligence of coplanarity detection.

[0105] Those of ordinary skill in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present application (including the claims) is limited to these examples; within the concept of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the embodiments of the present application as described above, and they are not provided in detail for the sake of brevity.

[0106] In addition, for simplicity of explanation and discussion, and in order not to make the embodiments of the present application difficult to understand, the well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Further, the devices may be shown in block diagram form in order to avoid making the embodiments of the present application difficult to understand, and this also takes into account the fact that the details of the implementation of these block diagram devices are highly dependent on the platform on which the embodiments of the present application are to be implemented (i.e., these details should be entirely within the understanding of those skilled in the art). In cases where specific details (such as circuits) are set forth to describe exemplary embodiments of the present application, it will be apparent to those skilled in the art that the embodiments of the present application may be implemented without these specific details or with variations of these specific details. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0107] Although the present application has been described in connection with specific embodiments of the present application, many alternatives, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art based on the foregoing description. For example, other memory architectures (such as dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0108] The embodiments of the present application are intended to cover all such alternatives, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the embodiments of the present application shall be included within the protection scope of the present application.

Claims

1. A chip coplanarity detection device, comprising: Linear drive mechanism, laser scanning head and detection table; The linear drive mechanism comprises a movable part and a driving part, wherein the driving part is used to drive the movable part to perform linear reciprocating motion along a preset movable trajectory; The laser scanning head is fixedly connected to the movable part, and when the driving part drives the movable part to move, the movable part drives the laser scanning head to perform linear reciprocating motion along a preset moving track; The detection table is used to place the chip to be detected, and the detection plane of the laser scanning head coincides with a side of the detection table close to the chip to be detected.

2. The chip coplanarity detection device according to claim 1, further comprising a housing; The housing comprises a base, an outer shell and a top cover, wherein the outer shell is fixedly connected to the upper surface of the base, and the lower surface of the top cover is fixedly connected to an end of the outer shell away from the base; The linear drive mechanism is fixedly connected to the base, and the linear drive mechanism and the laser scanning head are arranged inside the housing; The top cover also includes a first mounting hole, and the detection table is arranged in the first mounting hole.

3. The chip coplanarity detection device according to claim 2, wherein the housing further comprises a second mounting hole; The laser scanning head also includes a control cable, and the control cable passes through the second mounting hole and is connected to the controller.

4. The chip coplanarity detection device according to claim 3, further comprising a rolling device; The rolling device is annular, the outer ring of the rolling device is fixedly connected to the second mounting hole, the inner ring of the rolling device abuts against the control cable, and the outer ring is rotatably connected to the inner ring.

5. According to the chip coplanarity detection device according to claim 3, the laser scanning head is configured as follows: in response to the control signal output by the controller, the scanning surface of the laser scanning head scans the chip to be detected at least twice, and performs coplanarity detection on the chip to be detected based on at least two scanning images.

6. The chip coplanarity detection device according to claim 5, wherein the linear drive mechanism further comprises a guide rail, the movable part is arranged on the guide rail, and the drive part is arranged at one end of the guide rail; The linear drive mechanism is configured such that, in response to a control signal output by the controller, the drive unit drives the movable unit to move from the first end of the guide rail to the second end of the guide rail, and then from the second end of the guide rail to the first end of the guide rail. 7 . The chip coplanarity detection device according to claim 1 , further comprising a fixing fixture, wherein the fixing fixture is used to fix the chip to be detected on the upper surface of the detection table.

8. A chip coplanarity detection method, comprising: Scanning the surface of the chip to be tested to obtain a scanning dot matrix, and generating a first height map according to the scanning dot matrix; Calculating relative heights of at least four pins of the chip to be tested according to the first height map; The height difference of the pins is calculated according to the relative height, and in response to the height difference satisfying a preset error threshold, the chip to be tested is a qualified product.

9. The chip coplanarity detection method according to claim 8, wherein: Calculating the relative heights of at least four pins of the chip to be tested according to the first height map specifically includes: Identify the first height map to obtain a chip surface image and a chip pin image; Constructing a reference plane according to the chip surface image, and establishing a spatial rectangular coordinate system based on the reference plane; Calculating the spatial coordinates of the at least four pins according to the spatial rectangular coordinate system and the chip pin image; The relative height is calculated according to the spatial coordinates.

10. The chip coplanarity detection method according to claim 8, wherein: Scanning the surface of the chip to be tested to obtain a scanning dot matrix, and generating a first height map according to the scanning dot matrix specifically includes: Scanning the chip to be tested at least twice, aligning at least two groups of the scanning dot arrays to obtain a synthetic dot array; De-noising the synthetic point matrix to obtain the first height map.

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