A fully automated wafer laser marking device and method

Abstract

This invention discloses a fully automated wafer laser marking device and method, including a loading and unloading station, a CCD recognition system, a handling system, a wafer stage, and a laser marking system; it also includes a CCD positioning system and an adjustment mechanism. A hollow rotating platform is set on the P-axis linear module, with one wafer stage on the hollow rotating platform. When the moving part of the hollow rotating platform rotates around its rotation center, it can drive the wafer stage and the wafer to rotate together around the rotation center. Three sets of CCD image acquisition devices are evenly distributed around the circumference of the rotation center of the moving part of the hollow rotating platform and are fixed in place, used to collect data information on the outer contour (or edge) of the wafer. This invention is not only simple in structure, economical and practical, and highly automated, but also can first adjust the position of the wafer's straight edge to the correct position through CCD visual recognition, then calculate the position of the wafer's center, and finally control the galvanometer to automatically adjust the laser beam based on the position of the wafer's center, thereby achieving accurate marking of the wafer.

Description

Technical Field

[0001] This invention belongs to the field of wafer laser marking technology, and specifically discloses a fully automatic wafer laser marking device and method. Background Technology

[0002] Laser marking is a marking method that uses a high-energy-density laser to locally irradiate a workpiece, causing the surface material to vaporize or undergo a chemical reaction that changes color, thus leaving a permanent mark. Laser marking can create various texts, symbols, and patterns on the surface of workpieces, with character sizes ranging from millimeters to micrometers. This is particularly significant for product traceability, production classification, and anti-counterfeiting marking. The advantage of laser marking lies in its non-contact processing, which does not generate mechanical pressure or stress, resulting in minimal damage to the processed object. The focused laser beam is very small, with a small heat-affected zone, allowing for precise processing and enabling the completion of processes that are impossible using conventional methods.

[0003] Traditional wafer laser marking machines mainly use sensors to detect the reference straight edge of the wafer. If the reference straight edge is not in the correct position, the wafer position is adjusted by horizontal-vertical translation and rotation in the plane until the wafer is in the correct position. To achieve this, a very complex mechanical structure is required, and the operation is relatively cumbersome, time-consuming, and costly.

[0004] Chinese invention patent CN104385786A discloses a fully automatic wafer laser marking machine, comprising: a robotic arm system for picking up, placing, and transferring wafers, and sending wafer positioning signals to a CCD system; a CCD system for receiving the wafer positioning signals, scanning and processing real-time wafer image information, including a CCD positioning system for detecting wafer positional deviations and transmitting deviation signals to the laser marking system; and a laser marking system for adjusting the laser beam for marking based on the deviation signals from the CCD positioning system. The CCD system also includes a CCD recognition system for identifying the front and back of the wafer and determining whether the front and back information matches the information of the desired marking surface. It also includes a flipping system for controlling wafer flipping based on signals from the CCD recognition system. The laser marking system includes a galvanometer for adjusting the position of the laser beam. This invention achieves accurate marking of wafers by detecting and positioning characteristic positions of the wafer and automatically adjusting the laser beam. Compared with existing technologies, this invention eliminates the need for the complex mechanical structure of the XY-θ platform. Instead, the wafer can be accurately marked on feature positions simply by placing it directly on a standard marking platform. This results in a simple structure, convenient operation, and lower cost. The disclosed technical solution includes: a CCD positioning system for detecting wafer positional deviations and transmitting deviation signals to the laser marking system; and a laser marking system for adjusting the laser beam based on the deviation signals from the CCD positioning system. However, the laser marking system needs to compensate for the X, Y, and θ degrees of freedom of the wafer, thus requiring a high level of design expertise for the galvanometer structure. Since laser marking systems are typically purchased standard parts, modifying them is a time-consuming and labor-intensive undertaking. Therefore, this technical solution, which relies solely on the laser marking system adjusting the laser beam based on the deviation signals from the CCD positioning system, suffers from an uneconomical drawback.

[0005] Furthermore, the specification of Chinese invention patent CN114695226A discloses a fully automatic wafer back laser marking device, comprising: a mechanical system including a frame and a clamping assembly mounted on the frame for fixing and leveling the wafer to be marked; a loading and unloading system for placing the wafer to be marked and the marked wafer; a robotic arm system for picking up, placing, and transferring the wafer to be marked and the marked wafer; an automatic wafer edge-finding system for automatically calibrating the edge of the wafer to be marked transferred by the robotic arm system; a vision system for detecting the positioning data of the wafer to be marked after edge-finding calibration to obtain trial marking, and measuring the actual marking position to determine whether it exceeds the tolerance; and a dual laser system for performing trial marking based on the positioning data, and completing the marking of the wafer to be marked when the actual marking position does not exceed the tolerance. The method also discloses a fully automated wafer back laser marking method, which includes the following steps: a robotic arm system picks up a wafer to be marked from a wafer hopper on a loading and unloading system and places it on an automatic wafer edge finding system; the wafer to be marked is automatically calibrated for edge finding, and after edge finding is completed, a signal is sent to the upper vision detection component; the upper vision detection component automatically identifies the edge barcode or WAFER ID of the wafer to be marked; it determines whether the wafer to be marked can be marked, and if it can be marked, proceeds to the next step; if it cannot be marked, it is placed in an NG hopper; the wafer to be marked is placed on a wafer fixture, an electric rotary component drives the wafer to be marked to rotate, and an electric lifting platform drives the wafer pressure plate to flatten the wafer to be marked; a two-dimensional linear platform module drives a vision positioning component to locate the feature points on the front of the wafer to be marked, and obtains the positioning data for trial marking. The laser in the laser optical path assembly performs a trial marking on the wafer to be marked based on the positioning data. The lower vision inspection assembly measures the actual marking position and determines whether the marking position is out of tolerance. If it is out of tolerance, the wafer is placed in the NG (Not Tolerant) box; if it is within tolerance, marking continues. The laser optical path assembly marks all units of the wafer until marking is complete. The electric lifting assembly drives the wafer pressure plate to release the marked wafer, and the robotic arm system picks up the marked wafer and places it into the box. This prior art document discloses that the vision positioning assembly includes a lifting platform, a Z-axis electric platform mounted on the lifting platform, and a lifting platform connecting plate mounted on the Z-axis electric platform. A second CCD component is mounted on the lifting platform connecting plate via vision, and the second CCD component is aligned with the front of the wafer to be marked. The Z-axis electric platform drives the lifting platform connecting plate to move, thereby driving the second CCD component to move, facilitating its grasping of feature points on the front of the wafer to be marked and ensuring reliable positioning data.It should be noted that the comparative document has only one second CCD component. Although it can acquire feature points on the front side of the wafer, the premise for achieving laser marking using only the feature points on the front side of the wafer acquired by this single second CCD component is that the laser marking system needs to compensate for the X, Y, and θ degrees of freedom of the wafer. Therefore, the design requirements for the galvanometer structure are relatively high. However, laser marking systems are usually purchased standard parts, and processing and modifying them is a time-consuming and labor-intensive project. Therefore, this technical solution, which relies solely on the laser marking system adjusting the laser beam according to the deviation signal of the CCD positioning system for marking, has the disadvantage of being uneconomical.

[0006] Furthermore, the specification of Chinese utility model patent CN204504509U discloses a laser marking machine for marking wafers. Its features include: a marking machine body, a control component housed within the marking machine body, a feeding structure component mounted on the marking machine body, an angle correction structure component, a marking positioning and detection component, and a laser marking mechanism mounted on the marking machine body and cooperating with the marking positioning and detection component. The laser marking mechanism includes a laser generator mounted on the marking machine body, an optical path structure mounted on the laser generator for transmitting the laser emitted by the laser generator, and a marking mechanism mounted on the optical path structure for marking the wafer. The marking head for marking includes an angle correction structure component that can move back and forth along the X-axis and rotate circumferentially relative to the marking machine body. The marking positioning detection component includes a positioning detection mechanism for detecting whether the marking position of the wafer is correct and a marking support structure corresponding to the positioning detection structure for placing the wafer to be marked. The marking support structure is mounted on the marking machine body. The optical path structure includes a beam expander for expanding the laser beam, several reflectors for reflecting and transmitting the laser beam, an optical shutter for switching the laser beam, and a galvanometer. The feeding structure component can place the wafer to be marked on the angle correction component and can transfer the wafer that has been corrected on the angle correction component to the laser marking mechanism. In this utility model, the clamping structure places the wafer to be marked on the angle correction platform, the second CCD detection structure corrects the angle of the wafer to be marked, and then the clamping structure clamps the angle-corrected wafer and places it on the marking table, and presses the wafer with a pressure plate. The first CCD detection structure on the linear motion mechanism detects the marking position on the wafer and transmits it to the control component. The control component transmits the wafer position data to the marking head, and the marking head marks the wafer. The process involves rotating the wafer using a second CCD detection structure combined with an angle correction component, then transferring it to a marking table. The first CCD detection structure on the marking table detects the marking position on the wafer and transmits this information to a control component. The control component then transmits the wafer's position data to the marking head. However, during this transfer, errors from the robotic arm may still result in offset issues. Furthermore, this comparative document uses only one first CCD detection structure. While it can acquire feature points on the wafer's front side, achieving laser marking solely through this single structure requires the laser marking system to compensate for the wafer's X, Y, and θ degrees of freedom. This necessitates a high level of design expertise for the galvanometer structure. Since laser marking systems are typically purchased standard parts, modifying them is a time-consuming and labor-intensive undertaking. Therefore, this technical solution, which relies solely on the laser marking system adjusting the laser beam based on the deviation signal from the CCD positioning system, is uneconomical. Summary of the Invention

[0007] To address the technical problems existing in the prior art, this invention provides a fully automated wafer laser marking device. This device is not only simple in structure, economical and practical, and highly automated, but it also uses CCD visual recognition to first adjust the position of the wafer's straight edge to the correct position, then calculates the position of the wafer's center, and finally controls the galvanometer to automatically adjust the laser beam based on the wafer's center position, achieving accurate marking on the wafer. Compared with traditional technologies, this invention does not require a very complex mechanical mechanism; a simple and easy-to-operate mechanical structure is sufficient to achieve accurate marking on the wafer.

[0008] This invention discloses a fully automated wafer laser marking device, comprising: a loading and unloading station for placing and positioning wafer cassettes; a CCD recognition system for controlling a transport system to acquire wafers from the wafer cassettes; a transport system for transferring wafers to a wafer stage; a wafer stage for carrying wafers; a laser marking system for adjusting the laser beam via a galvanometer mechanism to mark the wafers on the wafer stage; and a CCD positioning system, including one CCD image acquisition unit for acquiring the coordinate parameters of the wafer's straight edge on the wafer stage and two CCD image acquisition units for acquiring the coordinate parameters of the wafer's circular arc on the wafer stage, the three CCD image acquisition units being evenly arranged relative to the Z-axis; and an adjustment mechanism including a P-axis linear module disposed between the CCD positioning system and the laser marking system. A hollow rotating platform rotatable around the Z-axis is mounted on the linear module. A wafer stage is fixed to the moving part of the hollow rotating platform, which can hold and hold the wafer. When the moving part of the hollow rotating platform rotates around its center of rotation, it drives the wafer stage and the wafer to rotate together around the center. Three sets of CCD image acquisition devices are evenly distributed around the circumference of the moving part of the hollow rotating platform and remain stationary. They are used to acquire data information on the outer contour (or edge) of the wafer. The line connecting the two endpoints of the wafer's straight edge on the wafer stage to the center of the hollow rotating platform is equal to the line connecting the two endpoints of the wafer's straight edge to the center of the hollow rotating platform. That is, the line connecting the two endpoints of the wafer's straight edge to the center of the hollow rotating platform forms an isosceles triangle. The wafer's straight edge forms a chord of a virtual circle. Therefore, rotating the wafer adjusts the position of the chord, ensuring that the chord is parallel to or coincides with the predefined theoretical wafer straight edge. In this invention, only one wafer is placed for each marking operation. The wafer stage is fastened to the moving part of the hollow rotating platform with screws. Three sets of light sources are fixed around the hollow rotating platform. Each light source corresponds one-to-one with one of the three CCD image acquisition units in the CCD positioning system, providing the environmental conditions for the CCD image acquisition units to operate. Another approach is to directly use a ring-shaped light source. The center of the ring-shaped light source is hollow, and the wafer stage can pass through it. Its function is the same as using three square light sources, providing the environmental conditions for the CCD image acquisition units to operate.

[0009] In a preferred embodiment of the present invention, after the transport system transfers the wafer to the wafer stage, the working steps of the CCD positioning system include:

[0010] S1, a CCD image acquisition device takes a picture of the wafer to obtain the wafer straight edge coordinate parameters and determines whether it meets the preset requirements. The preset requirements are: the wafer straight edge is parallel or coincident with the predefined theoretical wafer straight edge. If the requirements are not met, the position deviation information of the coordinate parameters of the two is transmitted to the adjustment mechanism, and the adjustment mechanism rotates the corresponding angle to make the two parallel or coincident.

[0011] S2, the three CCD image acquisition devices simultaneously take another picture of the wafer to obtain the coordinate information of the wafer edge within the field of view of each CCD image acquisition device, analyze and obtain the actual center coordinates of the wafer, and send the obtained actual center coordinates of the wafer to the laser marking system;

[0012] S3, the P-axis linear module moves the hollow rotary platform, wafer stage and wafer to the laser marking system. The galvanometer mechanism of the laser marking system corrects the deviation based on the actual center coordinates of the wafer, performs the laser marking action, and outputs the marking content to the correct position on the wafer.

[0013] In a preferred embodiment of the present invention, the loading and unloading station includes a bearing platform A, which is provided with a limiting groove capable of accommodating positioning jig plates of various sizes of material boxes, and a rectangular light source is fixedly connected to the side of the bearing platform A.

[0014] In a preferred embodiment of the present invention, the conveying system includes a multi-axis motion unit, the moving end of which is provided with a vacuum adsorption finger and a CCD recognition system, the CCD recognition system including a CCD image acquisition unit A.

[0015] In a preferred embodiment of the present invention, the moving end of the multi-axis motion unit is provided with an anti-collision buffer alarm mechanism. The anti-collision buffer alarm mechanism includes a base plate fixed to the moving end of the multi-axis motion unit. A finger support plate is connected to the base plate via a rotating shaft. A finger cover plate is connected to the finger support plate via a thread. The vacuum-adsorbed finger is pressed between the finger support plate and the finger cover plate. A tension spring is connected between the finger support plate and the base plate.

[0016] In a preferred embodiment of the present invention, the upper end face of the base plate is provided with a groove arranged perpendicular to the central axis of the rotation shaft, and the lower end face of the finger support plate is provided with an extended cylindrical platform, the diameter of which corresponds to the width of the groove; the upper end face of the finger support plate is provided with a groove feature for positioning and vacuum adsorbing the finger, and the lower end face of the finger cover plate is provided with a boss feature for engaging the groove, the groove depth of which is greater than the height of which is the boss feature, a sealing gasket is provided at the bottom of the groove feature and the end face of which is the boss feature, and a pneumatic connector and a proximity sensor are provided on the upper end face of the finger cover plate.

[0017] In a preferred embodiment of the present invention, the CCD positioning system includes a CCD mounting plate, the CCD mounting plate is connected to three CCD mounting brackets B, the included angle between any two CCD mounting brackets B is 120°, and each CCD mounting bracket B is connected to a CCD image acquisition device B extending along the Z-axis.

[0018] In a preferred embodiment of the present invention, a compressed air system is further included, comprising a manual sliding valve, an air filter, an oil mist separator, and a pressure reducing valve connected in series. The manual sliding valve is connected to an air source via a pipe joint and a hose, and the pressure reducing valve is connected to a first vacuum generator located in the conveying system and a second vacuum generator located in the adjusting mechanism via a pipe joint and a hose.

[0019] This invention also discloses a fully automated wafer laser marking method, which uses a fully automated wafer laser marking device to mark wafers with straight edges, and the steps are as follows:

[0020] S1, Place the wafer cassette onto the cassette fixture plate of the loading and unloading station;

[0021] S2, the handling system moves the CCD recognition system to the appropriate position, identifies the position information of each layer of wafers in the wafer cassette, counts the wafers, records and archives the missing layer information and feeds it back to the handling system.

[0022] S3, the handling system moves, driving the vacuum adsorption fingers to the loading and unloading station to pick up the wafers. After successful adsorption, the first vacuum generator sends a completion signal to the handling system.

[0023] S4: The handling system operates by transferring the wafer to the wafer stage. The first vacuum generator breaks the vacuum, and the vacuum adsorbs the fingers from the wafer. The second vacuum generator draws in the vacuum. After the wafer stage successfully adsorbs the wafer, the second vacuum generator sends a completion signal to the CCD positioning system.

[0024] S5, a CCD image acquisition device B acquires the wafer straight edge position information and compares it with the predefined theoretical wafer straight edge position to determine whether it meets the preset requirements. The preset requirements are: the wafer straight edge is parallel or coincides with the predefined theoretical wafer straight edge. If the requirements are not met, the position deviation information of the coordinate parameters of the two is sent to the adjustment mechanism.

[0025] S6. After receiving the wafer straight edge position deviation information sent by the CCD positioning system, the adjustment mechanism starts the hollow rotation platform to rotate at a small angle to adjust the wafer straight edge position.

[0026] S7, a CCD image acquisition device B continues to acquire wafer straight edge position information, analyzes and judges whether the actual direction of the wafer straight edge coincides with or is parallel to the predefined direction, and repeats the S6 action until the actual direction of the wafer straight edge coincides with or is parallel to the predefined direction.

[0027] S8, three CCD image acquisition units B simultaneously acquire wafer arc position information, calculate the actual center position of the wafer, and send the center position to the laser marking system;

[0028] S9, adjust the movement of the P-axis linear module in the mechanism to move the wafer from the CCD positioning station to the laser marking station;

[0029] S10, after the wafer is transferred to the laser marking station, the laser marking system performs galvanometer correction based on the actual center position of the wafer sent by the CCD positioning system, executes the laser marking action, and outputs the marking content to the correct position on the wafer.

[0030] S11, After laser marking is completed, the transport system operates, the vacuum adsorption finger moves to the marking station to pick up the wafer, the second vacuum generator breaks the vacuum, the wafer is removed from the wafer carrier, at the same time the first vacuum generator draws a vacuum, the vacuum adsorption finger adsorbs the wafer, and then the transport system operates to move the wafer from the marking station to the current picking layer of the wafer cassette.

[0031] S12, based on the missing material information recorded by the CCD recognition system, automatically skip the missing material layer, sequentially go to the next layer to pick up the wafer, repeat steps 3 to 12 until all wafers are marked;

[0032] S13, the handling system returns to a safe position;

[0033] S14, Remove the wafer cassette and the marked wafers from the cassette fixture plate of the loading / unloading station.

[0034] The beneficial effects of this invention are as follows: This invention not only enables fully automated laser marking of wafers of various sizes on a single device through the design of the material box fixture plate, making it highly practical; simultaneously, this invention creatively introduces a CCD positioning system and adjustment mechanism. It first adjusts the position of the wafer's straight edge to the correct position using CCD visual recognition, then calculates the wafer's center position based on CCD visual recognition, and finally controls the galvanometer to automatically adjust the laser beam, achieving accurate marking of the wafer. Compared to existing technologies disclosed in the background art, its adjustment mechanism only needs to control the rotation angle of the hollow rotating platform by one degree of freedom to achieve precise wafer positioning. Furthermore, this invention also discloses an anti-collision buffer alarm mechanism, which effectively solves the problem of damage to fingers and wafers caused by vacuum adsorption due to malfunctions or misoperation. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of a wafer processed by a fully automated wafer laser marking device according to the present invention;

[0036] Figure 2 This is a front axonometric view of a fully automated wafer laser marking device according to the present invention;

[0037] Figure 3 This is a rear-view axonometric view of a fully automated wafer laser marking device according to the present invention;

[0038] Figure 4 This is a top view of a fully automated wafer laser marking device according to the present invention;

[0039] Figure 5 This is an isometric view of the loading and unloading station of a fully automatic wafer laser marking device according to the present invention;

[0040] Figure 6 This is an isometric view of the CCD recognition system of a fully automated wafer laser marking device according to the present invention;

[0041] Figure 7 This is an isometric view of the handling system of a fully automated wafer laser marking device according to the present invention;

[0042] Figure 8 This is an isometric view of the anti-collision buffer alarm mechanism of a fully automatic wafer laser marking device according to the present invention;

[0043] Figure 9 This is a schematic diagram of the anti-collision buffer alarm mechanism of a fully automatic wafer laser marking device according to the present invention;

[0044] Figure 10 This is an isometric view of the CCD positioning system of a fully automated wafer laser marking device according to the present invention;

[0045] Figure 11This is an isometric view of the adjustment mechanism of a fully automatic wafer laser marking device according to the present invention;

[0046] Figure 12 This is an isometric sectional view of the adjustment mechanism of a fully automatic wafer laser marking device according to the present invention;

[0047] Figure 13 This is an isometric view of the laser marking system of a fully automatic wafer laser marking device according to the present invention;

[0048] Figure 14 This is a schematic diagram of the compressed air system of a fully automatic wafer laser marking device according to the present invention;

[0049] Figure 15 This is a schematic diagram of the dust extraction and purification system of a fully automatic wafer laser marking device according to the present invention;

[0050] Figure 16 This is a schematic diagram of the material box fixture plate of a fully automatic wafer laser marking device according to the present invention;

[0051] Figure 17 This is a schematic diagram illustrating the working condition of the present invention without wafer adjustment;

[0052] Figure 18 This is a schematic diagram of the first type of working condition requiring wafer rotation adjustment according to the present invention;

[0053] Figure 19 This is a schematic diagram of the second type of working condition requiring wafer rotation adjustment according to the present invention;

[0054] Figure 20 This is a schematic diagram of the third working condition of the present invention that requires adjustment of the rotating wafer;

[0055] In the diagram, 10-loading / unloading station, 101-wafer cassette; 102-cassette fixture plate, 103-carrying platform A, 20-CCD recognition system, 201-CCD image acquisition unit A, 202-CCD mounting bracket A, 203-rectangular light source, 204-rectangular light source mounting plate, 30-transfer system, 301-X-axis linear module, 302-Y-axis linear module, 303-Z-axis linear module, 304-anti-collision buffer alarm mechanism, 305-vacuum adsorption finger, 40-CCD positioning system, 401-CCD image acquisition unit B (numbered B1 / B2 / B3), 402-CCD mounting bracket B, 403-CCD mounting plate, 404-square light source, 405-square light source mounting plate, 406- Sheet metal bracket, 50-adjustment mechanism, 501-P-axis linear module, 502-hollow rotary platform, 503-wafer stage, 504-fluid slip ring, 505-wafer stage mounting base, 60-laser marking system, 601-field lens, 602-galvanometer, 603-optical path module, 604-lifting slide, 605-bearing platform B, 606-laser, 70-compressed air system, 701-hand slide valve, 702-air filter, 703-oil mist separator, 704-pressure reducing valve, 705-pipe fittings and hoses, 706-first vacuum generator, 707-second vacuum generator, 80-dust extraction and purification system, 801-dust hood, 802-non-metallic corrugated pipe, 803-dust extraction bracket, 804-bracket mounting plate. Detailed Implementation

[0056] The technical solutions (including preferred technical solutions) of the present invention will be further described in detail below with reference to the accompanying drawings and by way of listing some optional embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0057] like Figure 1-6 As shown, this invention discloses a fully automated wafer laser marking device, including...

[0058] The loading / unloading station 10 is used for placing and positioning wafer cassettes, sending material arrival signals to the handling system so that the system can remove unmarked wafers from the cassettes and place marked wafers into them. It mainly includes wafer cassettes and cassette fixtures, which are equipped with limiting slots of different shapes (compatible with different sizes of wafer cassette designs) for placing and positioning wafer cassettes, and a support platform A (for supporting the wafer cassette fixture and other components).

[0059] The CCD recognition system 20 is used to identify which layer in the wafer cassette is missing material, record and archive the missing layer information, and feed it back to the handling system to guide the handling system to retrieve material from the wafer cassette. It automatically skips the missing layer when it reaches it. It mainly includes a set of CCD image acquisition units, a CCD mounting base, a rectangular light source, a backlight for the CCD recognition system, and a rectangular light source mounting plate.

[0060] The handling system 30 is used for picking up, placing, and transferring wafers. It mainly includes X, Y, and Z axis linear modules for translational movement in three directions during wafer handling; an anti-collision buffer alarm mechanism to solve the problem of vacuum adsorption fingers and wafers colliding and breaking due to malfunctions or misoperation; and vacuum adsorption fingers with ventilation slots to support the wafers during handling.

[0061] Wafer stage 503 is used to support wafers;

[0062] The laser marking system 60 is used to mark the wafer located on the wafer stage by adjusting the laser beam through the galvanometer mechanism;

[0063] Also includes

[0064] The CCD positioning system 40 is used to acquire wafer edge position information and feed it back to the adjustment mechanism. With the assistance of the adjustment mechanism, the direction of the wafer's straight edge is adjusted to be consistent with (coinciding with or parallel to) the preset direction, and finally the actual center position of the wafer is analyzed and calculated. It mainly includes three sets of CCD image acquisition units, a CCD mounting bracket, a CCD mounting plate, a square light source, a square light source mounting plate, and a sheet metal bracket.

[0065] The adjustment mechanism 50, upon receiving the wafer straight edge position information, activates the hollow rotary platform, rotating at a small angle to adjust the direction of the wafer straight edge until it is in the correct orientation. The wafer is then moved from the CCD positioning station to the marking station via the P-axis linear module, sending a transfer signal to the laser marking system. The mechanism mainly includes: a P-axis linear module for translating the wafer between the CCD positioning station and the marking station; a hollow rotary platform for rotating and adjusting the wafer's position; a wafer stage for supporting the wafer for positioning and marking; a fluid slip ring for connecting the wafer stage to compressed air; and a wafer stage mounting base.

[0066] The CCD positioning system 40 includes a CCD image acquisition unit B for acquiring the wafer straight edge coordinate parameters of the wafer located on the wafer stage 503 and two CCD image acquisition units B for acquiring the wafer arc coordinate parameters of the wafer located on the wafer stage 503. The three CCD image acquisition units B are evenly arranged relative to the Z-axis.

[0067] The adjustment mechanism 50 includes a P-axis linear module 501 positioned between the CCD positioning system 40 and the laser marking system 60. The P-axis linear module 501 has a hollow rotating platform 502 that can rotate around the Z-axis. A wafer stage 503 is mounted on the hollow rotating platform 502, which can hold and hold a wafer. When the moving part of the hollow rotating platform 502 rotates around its rotation center, it can drive the wafer stage 503 and the wafer to rotate together around the rotation center. Three sets of CCD image acquisition units B are evenly distributed around the circumference of the moving part of the hollow rotating platform and remain stationary, used to acquire data information on the outer contour (or edge) of the wafer. The line connecting the two endpoints of the straight edge of the wafer on the wafer stage 503 to the center of the hollow rotating platform 502 is equal. Only one wafer is placed for each marking operation, and the wafer stage is fastened to the moving part of the hollow rotating platform with screws. Three sets of light sources are fixed around the hollow rotating platform. Each light source corresponds one-to-one with one of the three CCD image acquisition units in the CCD positioning system, providing the environmental conditions for the CCD image acquisition units to operate. (Another approach is to use a ring-shaped light source. The center of the ring-shaped light source is hollow, allowing the wafer stage to pass through it. Its function is the same as using three square light sources, providing the environmental conditions for the CCD image acquisition units to operate.)

[0068] The laser marking system 60, after receiving the actual center position information of the wafer from the CCD positioning system, automatically corrects the deviation of the laser beam by combining the predefined marking content with the relative position deviation of the theoretical straight edge of the wafer using the galvanometer mechanism, and performs marking. It mainly includes a field lens; a galvanometer; an optical path module; a lifting slide; a support platform B; and a laser.

[0069] Compressed air system 70: Used to generate vacuum suction force for vacuum suction fingers and wafer stage adsorption. Mainly includes a hand slide valve; air filter; oil mist separator; pressure reducing valve; several pipe fittings and hoses; vacuum generator 1, used to provide vacuum suction force to vacuum suction fingers; and air generator 2, used to provide vacuum suction force to the wafer stage.

[0070] Dust extraction and purification system 80: Used to purify the fumes generated during laser marking, preventing dust contamination of wafers and the working environment. Main components include a dust extraction hood; non-metallic corrugated pipe; dust extraction bracket; and bracket mounting plate.

[0071] The method for acquiring wafer parameters based on the CCD positioning system 40 of this invention is as follows: Three sets of CCD image acquisition units B (each assigned a number B1 / B2 / B3) in the CCD positioning system construct a coordinate system according to the actual mechanical component installation position. B1 is used to acquire the wafer's straight edge direction parameters, and B2 / B3 are used to acquire the wafer's arc parameters at the corresponding orientation. First, when the wafer is placed on the wafer stage 503 of the CCD positioning station, the CCD image acquisition unit B1 takes its first photograph to acquire the wafer's edge coordinate parameters. It then determines whether the wafer's straight edge direction is consistent with the straight edge direction of the set standard state. If not, the position deviation information is transmitted to the adjustment mechanism. Then, the hollow rotating platform rotates at a small angle. After rotation, the CCD image acquisition unit B1 takes its second photograph to acquire the wafer's edge coordinate parameters and again determines whether the wafer's straight edge direction is consistent with the straight edge direction of the set standard state. If still not consistent, the hollow rotating platform continues to rotate at a small angle. This process is repeated until the direction of the wafer's straight edge is consistent with the straight edge direction of the set standard state (the straight edges coincide or are parallel). Once the wafer's straight edge reaches the required state, the three sets of CCD image acquisition devices B (B1 / B2 / B3) begin taking pictures to obtain the coordinate information of the wafer edge within their respective fields of view, and analyze and calculate the actual center coordinates of the wafer.

[0072] The method for adjusting a wafer by combining the CCD positioning system and the adjustment mechanism is as follows: With the assistance of the hollow rotating platform of the adjustment mechanism, the CCD positioning system adjusts the direction of the wafer's straight edges until the required position is achieved. The CCD positioning system sends the wafer's center coordinates to the laser marking system, while simultaneously, the P-axis linear module of the adjustment mechanism moves the wafer from the CCD identification station to the laser marking station. After receiving the wafer's center position obtained from the CCD positioning system, the laser marking system uses the correction function of the galvanometer mechanism to actually correct the marking content relative to the wafer's center positioning position, ensuring that the marking content is output in the correct position.

[0073] Preferably, after the transport system 30 transfers the wafer to the wafer stage 503, the working steps of the CCD positioning system 40 include:

[0074] S1, a CCD image acquisition device B takes a picture of the wafer to obtain the wafer straight edge coordinate parameters and determines whether it meets the preset requirements. The preset requirements are: the wafer straight edge is parallel or coincident with the predefined theoretical wafer straight edge. If the requirements are not met, the position deviation information of the coordinate parameters of the two is transmitted to the adjustment mechanism 50. The adjustment mechanism 50 rotates the corresponding angle to make the two parallel or coincident.

[0075] S2, the three CCD image acquisition devices B simultaneously take pictures of the wafer again to obtain the coordinate information of the wafer edge within the field of view of each CCD image acquisition device B, analyze and obtain the actual center coordinates of the wafer, and send the obtained actual center coordinates of the wafer to the laser marking system 60.

[0076] S3, the P-axis linear module 501 translates the hollow rotary platform 502 to the laser marking system 60. The galvanometer mechanism of the laser marking system 60 corrects the deviation based on the actual center coordinates of the wafer, performs the laser marking action, and outputs the marking content to the correct position on the wafer.

[0077] like Figure 17-20 As shown, it discloses various operating conditions for wafer rotation adjustment:

[0078] exist Figure 17 In this process, the initial state of the wafer is consistent with the ideal state of the wafer, so no adjustment is needed and it can be marked directly;

[0079] exist Figure 18 In this context, the relationship between the initial state of the wafer and the ideal state of the wafer is as follows: the theoretical wafer center does not coincide with the theoretical wafer center, but the straight edge of the wafer is parallel to the theoretical straight edge. Therefore, the wafer needs to be rotated around the center of the wafer stage for marking.

[0080] exist Figure 19 In this context, the relationship between the initial state and the ideal state of the wafer is as follows: the theoretical center of the wafer coincides with the center of the wafer, but the straight edges are not parallel. Therefore, the wafer does not need to rotate around the center of the wafer stage. Only the actual center position of the wafer is identified and marked.

[0081] exist Figure 20 In the process, the relationship between the initial state of the wafer and the ideal state of the wafer is as follows: the theoretical wafer center does not coincide with the wafer center position, and the wafer straight edge is not parallel to the theoretical straight edge. Therefore, the wafer first needs to be rotated around the center of the wafer stage by a certain angle to analyze and determine whether it is parallel to the theoretical wafer straight edge. The second step shown in the figure is that it is still not parallel after rotation, so it needs to be rotated around the center of the wafer stage by a certain angle again to ensure that the straight edges of the two are parallel, and then marked.

[0082] Preferably, the loading / unloading station 10 includes a support platform A103, on which a limiting groove is provided that can accommodate positioning jig plates 102 of various sizes of material boxes. A rectangular light source 203 is fixedly connected to the side of the support platform A103. The limiting groove is as follows: Figure 16As shown, different shaped limiting slots are available to accommodate the positioning and installation of 4-inch / 5-inch / 6-inch wafer cassettes. A rectangular light source mounting plate 204 is installed at an appropriate distance on the back of the wafer cassette 101 to fix the rectangular light source 203. The rectangular light source 203 provides backlight illumination for the CCD recognition system 20 during the wafer counting process of the wafer cassette 101, assisting the CCD image acquisition unit A201 in identifying wafers. The rectangular light source mounting plate has adjustable holes for easy adjustment of the position of the rectangular light source 203.

[0083] Preferably, the conveying system 30 includes a multi-axis motion unit, and the moving end of the multi-axis motion unit is provided with a vacuum adsorption finger 305 and a CCD recognition system 20, which includes a CCD image acquisition unit A201.

[0084] Preferably, the multi-axis motion unit includes an X-axis linear module 301, a Y-axis linear module 302, and a Z-axis linear module 303. All three modules—X-axis, Y-axis, Z-axis, and P-axis—are high-precision, dustproof linear modules equipped with servo motors to prevent contamination of the working environment. X / Y / Z / P directional indicators are used to distinguish the movement direction of the slide on the linear module. An anti-collision buffer alarm mechanism 304 is mounted on the slide of the Y-axis linear module 302 using pin-mounted positioning screws. Tension springs are provided on both sides of the anti-collision buffer alarm mechanism 304 to prevent wafer breakage while simultaneously issuing an alarm signal and controlling the Z-axis linear module to stop in time. The vacuum adsorption finger 305 has tiny annular air grooves with internal ventilation holes, allowing compressed air to be guided from the head end to the tail end for adsorption and wafer support. The second vacuum generator 707 is connected to the anti-collision buffer alarm mechanism 304 via an air pipe and connector. The air inlet at the tip of the vacuum adsorption finger 305 is sealed to the anti-collision buffer alarm mechanism 304 to prevent air leakage. The surface of the vacuum adsorption finger 305 is coated with conductive Teflon material to release static electricity that may be generated on the wafer. When the vacuum adsorption finger 305 malfunctions and collides with the wafer stage 503, the finger support plate 30404, the finger cover plate 30409, and the vacuum adsorption finger will deflect. The tension spring 30403 will be further stretched, increasing the distance between the proximity sensor 30411 and the base plate 30401. This will then output an alarm signal to the handling system 30 to stop the Z-axis linear module 303, thereby preventing the vacuum adsorption finger 305 from breaking due to hard impact and damaging the wafer. After the reset operation, under the action of the tension spring 30403, the finger support plate 30404, finger cover plate 30409, vacuum adsorption finger 305 and proximity sensor 30411 can be returned to their original state, and the alarm signal can be released.

[0085] Preferably, the moving end of the multi-axis motion unit is provided with an anti-collision buffer alarm mechanism 304. The anti-collision buffer alarm mechanism 304 includes a base plate 30401 fixed to the moving end of the multi-axis motion unit. A finger support plate 30404 is connected to the base plate 30401 via a rotating shaft 30406. A finger cover plate 30409 is connected to the finger support plate 30404 via a thread. A vacuum-adsorbed finger 305 is pressed between the finger support plate 30404 and the finger cover plate 30409. A tension spring 30403 is connected between the finger support plate 30404 and the base plate 30401.

[0086] Preferably, the upper end face of the base plate 30401 is provided with a groove arranged perpendicularly to the central axis of the rotation shaft 30406, and the lower end face of the finger support plate 30404 is provided with an extended cylindrical platform, the diameter of which corresponds to the width of the groove; the upper end face of the finger support plate 30404 is provided with a groove feature for positioning the vacuum adsorption finger 305, and the lower end face of the finger cover plate 30409 is provided with a boss feature for engaging the groove, the groove depth being greater than the height of the boss feature, and sealing gaskets being provided at the bottom of the groove feature and the end face of the boss feature; and a pneumatic connector 30410 and a proximity sensor 30411 are provided on the upper end face of the finger cover plate 30409.

[0087] Specifically, the base plate 30401 has a groove whose width matches the diameter of the bottom cylinder of the finger support plate 30404, forming a small clearance fit. This restricts the left and right movement of the finger support plate when it rotates around 30404, allowing it to move only vertically along the groove. The top of the finger support plate 30404 has a recessed groove, and the lower part of the finger cover plate 30409 has a protrusion. The two are fixed by positioning pins and screws, and there is a certain space between the protrusion and the recessed groove for clamping the vacuum-adsorbed finger 305. A sealing gasket is provided between the vacuum-adsorbed finger 305 and the finger cover plate 30409 and the finger support plate 30404 to ensure good airway sealing. The top of the finger cover plate 30409 has a threaded interface for installing a pneumatic connector 30410 to achieve compressed air input. Supports 30402 for tension springs are installed at corresponding positions on both sides of the base plate 30401 and the finger support plate 30404 for installing tension springs 30403. The finger support plate 30404 and the finger cover plate 30409 have through holes to facilitate the installation of the proximity sensor 30411 by locking it in place with a thin hexagonal nut. The sensing side of the proximity sensor 30411 is close to the top surface of the base plate 30401.

[0088] Under normal operating conditions, the cylinder at the bottom of the finger support plate 30104 will fit into the groove of the base plate 30401, the tension spring 30403 will be in a pre-stretched state, the vacuum-adsorbed finger 305 will be usable and will not deflect, and the distance between the proximity sensor 30411 and the base plate will be within the set sensing range, and no alarm signal will be output.

[0089] When the vacuum suction finger 305 malfunctions and collides with the wafer stage 503, the finger support plate 30404, finger cover plate 30409, and vacuum suction finger 305 will deflect. The tension spring 30403 will be further stretched, increasing the distance between the proximity sensor 30411 and the substrate 30401. This triggers an alarm signal to the handling system 30, stopping the Z-axis linear module 303 to prevent the vacuum suction finger 305 from breaking due to a hard impact and damaging the wafer. After a reset operation, the tension spring 30403 will return the finger support plate 30404, finger cover plate 30409, vacuum suction finger 305, and proximity sensor 30411 to their original state, thus clearing the alarm signal.

[0090] Preferably, the CCD positioning system 40 includes a CCD mounting plate 403, which is connected to three CCD mounting brackets B402. The included angle between any two CCD mounting brackets B402 is 120°, and each CCD mounting bracket B402 is connected to a CCD image acquisition device B extending along the Z-axis.

[0091] Preferably, it also includes a compressed air system 70, which includes a manual slide valve 701, an air filter 702, an oil mist separator 703 and a pressure reducing valve 704 connected in series. The manual slide valve 701 is connected to an air source through a pipe joint and a hose 705, and the pressure reducing valve 704 is connected to a first vacuum generator 706 located in the conveying system 30 and a second vacuum generator 707 located in the adjustment mechanism 50 through a pipe joint and a hose 705.

[0092] Preferably, the system also includes a dust extraction and purification system 80, which includes a dust extraction hood 801. The dust extraction hood 801 is a sheet metal part in the shape of a flared mouth. One end of the dust extraction hood 801 is sealed and connected to a non-metallic corrugated pipe 802, and the other end of the dust extraction hood 801 is connected to an external independent purification device or a negative pressure dust removal pipe in the production area. A dust extraction bracket 803 with adjustable height is connected to the dust extraction hood 801, and the dust extraction bracket 803 is fixed by a bracket mounting plate 804.

[0093] Preferably, the hollow rotating platform 502 of the adjustment mechanism 50 of the present invention is fixed to the slider of the P-axis linear module 501 by screws. The center of the rotating platform 502 has a through hole that allows a compressed air hose to pass through. The wafer stage mounting base 505 also has a central through hole and is fixed to the hollow rotating platform 502 by screws. The bottom of the wafer stage 503 has a boss with a threaded hole for connecting the moving end of the fluid slip ring 504. The other end of the fluid slip ring 504 is a stator end, which is connected to the air pipe from the vacuum port of the vacuum generator 2 relative to the air pipe connector. The fluid slip ring 504 has a through hole in the center, allowing compressed air to pass freely. The moving end of the fluid slip ring 504 can rotate relative to the center of the stator end. The wafer stage 503 has a large diameter hole in the center and several regularly arranged small holes on the top to increase the contact area between the wafer stage 503 and the wafer. The wafer stage 503 is made of 316L material, and the top surface has a glossy finish.

[0094] Preferably, in the laser marking system 60 of the present invention, the field lens 601 and the galvanometer 602 are connected by threads. The optical path module 603 is a series of components that the laser passes through during its transmission after being emitted from the laser 606. The optical path module 603 is mounted on the support plate of the lifting slide 604, which is mainly used to adjust the working distance between the field lens 601 and the wafer marking surface. It is mounted on the support platform B605 and fastened with screws.

[0095] Preferably, the purpose of the compressed air system 70 of the present invention is to provide clean positive pressure gas for the first vacuum generator 706 and the second vacuum generator 707 to generate a vacuum negative pressure to adsorb wafers when needed. A manual sliding valve 701 is used to control the on / off of compressed air input from the air source. An air filter 702 and an oil mist separator 703 are used to filter the compressed air. A pressure reducing valve 704 is used to regulate the input compressed air pressure. Pipe fittings and hoses 705 are common air circuit connection components. The first vacuum generator 706 and the second vacuum generator 707 are integrated vacuum generators, small in size and fully functional.

[0096] The dust hood 801 described in this invention is a flared sheet metal part made of stainless steel. One end of a non-metallic corrugated pipe 802 is fitted onto the small end of the flared pipe of the dust hood and is sealed to prevent air leakage. The other end is connected to an external independent purification device or a negative pressure dust removal pipe in the production area. The dust collection bracket 803 is height-adjustable and is mounted on a bracket mounting plate 804.

[0097] This invention also discloses a fully automated wafer laser marking method, which uses a fully automated wafer laser marking device to mark wafers with straight edges, and the steps are as follows:

[0098] S1, place the wafer cassette 101 onto the cassette fixture plate 102 of the loading and unloading station 10;

[0099] S2, the handling system 30 moves the CCD recognition system 20 to a suitable position, identifies the position information of each layer of wafers in the wafer cassette 101, counts the wafers, records and archives the missing layer information and feeds it back to the handling system 30.

[0100] S3, the conveying system 30 operates, driving the vacuum adsorption finger 305 to the loading and unloading station 10 to pick up the wafer. After successful adsorption, the first vacuum generator 706 sends a completion signal to the conveying system 30.

[0101] S4: The handling system 30 operates, transferring the wafer to the wafer stage 503. The first vacuum generator 706 breaks the vacuum, the vacuum adsorption finger 305 detaches from the wafer, the second vacuum generator 707 draws in the vacuum, and after the wafer stage 503 successfully adsorbs the wafer, the second vacuum generator 707 sends a completion signal to the CCD positioning system 40.

[0102] S5, a CCD image acquisition device B acquires the wafer straight edge position information and compares it with the predefined theoretical wafer straight edge position to determine whether it meets the preset requirements. The preset requirements are: the wafer straight edge is parallel or coincides with the predefined theoretical wafer straight edge. If the requirements are not met, the deviation information is sent to the adjustment mechanism.

[0103] S6, after receiving the wafer straight edge position deviation information sent by the CCD positioning system, the adjustment mechanism 50 starts the hollow rotation platform to rotate at a small angle to adjust the wafer straight edge position.

[0104] S7, a CCD image acquisition device B continues to acquire wafer straight edge position information, analyzes and judges whether the actual direction of the wafer straight edge coincides with or is parallel to the predefined direction, and repeats the S6 action until the actual direction of the wafer straight edge coincides with or is parallel to the predefined direction.

[0105] S8, three CCD image acquisition units B simultaneously acquire wafer arc position information, calculate the actual center position of the wafer, and send the center position to the laser marking system;

[0106] S9, adjust the action of the P-axis linear module 501 in the adjustment mechanism 50 to move the wafer from the CCD positioning station to the laser marking station;

[0107] S10, after the wafer is transferred to the laser marking station, the laser marking system 60 performs galvanometer correction based on the actual center position of the wafer sent by the CCD positioning system, executes the laser marking action, and outputs the marking content to the correct position on the wafer.

[0108] S11, after laser marking is completed, the transport system 30 is activated, the vacuum adsorption finger 305 moves to the marking station to pick up the wafer, the second vacuum generator 707 breaks the vacuum, the wafer is separated from the wafer carrier 503, at the same time the first vacuum generator 706 draws in the vacuum, the vacuum adsorption finger 305 adsorbs the wafer, and then the transport system is activated to move the wafer from the marking station to the current picking layer of the wafer cassette 101;

[0109] S12, based on the missing material information recorded by the CCD recognition system, automatically skip the missing material layer, sequentially go to the next layer to pick up the wafer, repeat steps 3 to 12 until all wafers are marked;

[0110] S13, the handling system returns to a safe position;

[0111] S14, the wafer cassette 101 and the marked wafers are removed from the cassette fixture plate 102 of the loading and unloading station.

[0112] In this invention, CCD is an abbreviation for Charge-coupled Device, also known as an image sensor. It is a semiconductor device that can directly convert optical signals into analog current signals. After amplification and analog-to-digital conversion, the current signal can be used to acquire, store, transmit, process, and reproduce images. The CCD recognition system 20 and CCD positioning system 40 are named differently because the CCD ultimately serves different purposes. CCD image acquisition device A 201 and CCD image acquisition device B 401 are both types of CCD image sensors and can be the same model in practical applications. CCD mounting bracket A 202 has a Y-axis adjustable function, which facilitates the adjustment of the focus of CCD image acquisition device A 201 to a suitable position after installation. In this example, three sets of CCD image acquisition devices B 401 are used, which are installed on three CCD mounting brackets B 402 respectively. The three sets of CCD mounting brackets B 402 are evenly distributed at 120° intervals on the CCD mounting plate 403 and can be adjusted in a small range around the center of the CCD mounting plate 403. The CCD positioning system 40 is installed next to the laser marking system 60, forming a paraxial relationship with its upper field mirror 601. Three square light sources 404 are directly opposite the three CCD image acquisition units B401, mounted at a 120° angle to each other on the square light source mounting plate 405, providing backlighting for the CCD image acquisition units B401. The sheet metal bracket 406 connects the P-axis linear module 501 to the square light source mounting plate 405.

[0113] Those skilled in the art will readily understand that the above are merely preferred embodiments of the present invention and are not intended to limit the invention. Any modifications, combinations, substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A full-automatic wafer laser marking device, comprising a loading and unloading work station (10) for placing and positioning a wafer magazine; a CCD recognition system (20) for controlling a handling system (30) to obtain a wafer from the wafer magazine; the handling system (30) for transferring the wafer to a wafer table; the wafer table (503) for carrying the wafer; a laser marking system (60) for marking the wafer on the wafer table by adjusting a laser beam through a galvanometer mechanism; characterized in that it further comprises an adjustment mechanism (50) comprising a P-axis linear module (501) disposed between the CCD positioning system (40) and the laser marking system (60), the P-axis linear module (501) being provided with a hollow rotating platform (502) rotatable around a Z-axis, the hollow rotating platform (502) being provided with a wafer table (503), and when the mover part of the hollow rotating platform (502) rotates around its rotation center, the wafer table (503) and the wafer on the wafer table (503) can rotate around the rotation center of the hollow rotating platform (502); the CCD positioning system (40) comprising one CCD image collector B for obtaining wafer straight edge coordinate parameters of the wafer on the wafer table (503) and two CCD image collectors B for obtaining wafer arc coordinate parameters of the wafer on the wafer table (503), the three CCD image collectors B being circumferentially distributed around the rotation center of the mover part of the hollow rotating platform (502); after the handling system (30) transfers the wafer to the wafer table (503), the working steps of the CCD positioning system (40) include S1, one CCD image collector B photographs the outer contour of the wafer to obtain wafer straight edge coordinate parameters of the wafer, and judges whether the wafer straight edge is parallel to or coincides with a pre-defined theoretical wafer straight edge, if not, the positional deviation information of the two coordinate parameters is transmitted to the adjustment mechanism (50), and the adjustment mechanism (50) rotates by a corresponding angle to realize parallelism or coincidence of the two; S2, the three CCD image collectors B simultaneously photograph the wafer again to obtain coordinate information of the wafer edge in the corresponding field of view of each CCD image collector B, analyze and obtain the actual center coordinate of the wafer, and send the obtained actual center coordinate of the wafer to the laser marking system (60); S3, the P-axis linear module (501) translates the hollow rotating platform (502), the wafer table (503) and the wafer to the laser marking system (60), the galvanometer mechanism of the laser marking system (60) corrects deviation based on the actual center coordinate of the wafer, performs laser marking action, and outputs the marking content to the correct position on the wafer.

2. The full-automatic wafer laser marking device according to claim 1, characterized in that: The loading and unloading work station (10) comprises a carrying platform A (103) provided with a limiting groove capable of positioning a variety of size magazine jig plates (102), and a rectangular light source (203) is fixed beside the carrying platform A (103).

3. The fully automatic wafer laser marking device according to claim 1, characterized in that: The carrying system (30) comprises a multi-axis motion unit, a vacuum suction finger (305) and a CCD identification system (20) are arranged on the moving end of the multi-axis motion unit, and the CCD identification system (20) comprises a CCD image collector A (201).

4. The fully automatic wafer laser marking device according to claim 3, characterized in that: The moving end of the multi-axis motion unit is provided with a collision prevention and buffering alarm mechanism (304), the collision prevention and buffering alarm mechanism (304) comprises a base plate (30401) fixed to the moving end of the multi-axis motion unit, a finger supporting plate (30404) is connected to the base plate (30401) through a rotating shaft (30406), a finger cover plate (30409) is connected to the finger supporting plate (30404) through screw threads, the vacuum suction finger (305) is pressed between the finger supporting plate (30404) and the finger cover plate (30409), and a tension spring (30403) is connected between the finger supporting plate (30404) and the base plate (30401).

5. The fully automatic wafer laser marking device according to claim 4, characterized in that: The upper end surface of the base plate (30401) is provided with a groove perpendicular to the central axis of the rotating shaft (30406), the lower end surface of the finger supporting plate (30404) is provided with an epitaxial cylindrical table, the diameter of the cylindrical table corresponds to the width of the groove, the upper end surface of the finger supporting plate (30404) is provided with a sink feature for positioning the vacuum suction finger (305), the lower end surface of the finger cover plate (30409) is provided with a boss feature for sink cooperation, the groove depth of the sink feature is greater than the height of the boss feature, and sealing pads are arranged on the groove bottom of the sink feature and the end surface of the boss feature, and a pneumatic connector (30410) and a proximity sensor (30411) are arranged on the upper end surface of the finger cover plate (30409).

6. The fully automatic wafer laser marking device according to claim 1, characterized in that: The CCD positioning system (40) comprises a CCD mounting plate (403), three CCD mounting supports B (402) are connected to the CCD mounting plate (403), the included angle between any two CCD mounting supports B (402) is 120°, and one CCD image collector B (401) extending along the Z axis is connected to each CCD mounting support B (402).

7. The fully automatic wafer laser marking device according to claim 1, characterized in that: The compressed air system (70) comprises a hand slide valve (701), an air filter (702), an oil mist separator (703) and a pressure reducing valve (704) connected in series, the hand slide valve (701) is connected to an air source through a pipe joint and a hose (705), and the pressure reducing valve (704) is connected to a first vacuum generator (706) located in the carrying system (30) and a second vacuum generator (707) located in the adjusting mechanism (50) through a pipe joint and a hose (705).

8. A fully automatic wafer laser marking method, characterized by: The full-automatic wafer laser marking device is used for marking a wafer with a straight edge, and the steps are as follows: S1, placing a wafer box (101) on a box jig plate (102) of a loading and unloading work station (10); S2, the handling system (30) moves the CCD recognition system (20) to the appropriate position, identifies the position information of each layer of wafers in the wafer magazine (101), counts the wafers, records the information of the wafer-lacking layer and feeds back to the handling system (30); S3, the handling system (30) moves the vacuum suction fingers (305) to the wafer taking station (10) to take wafers, and after successful suction, the first vacuum generator (706) sends a completion signal to the handling system (30); S4: the handling system (30) moves the wafer to the wafer loading platform (503), the first vacuum generator (706) breaks the vacuum, the vacuum suction fingers (305) are separated from the wafer, the second vacuum generator (707) is vacuumized, and after the wafer loading platform (503) successfully sucks the wafer, the second vacuum generator (707) sends a completion signal to the CCD positioning system (40); S5, a CCD image collector B (401) collects the straight edge position information of the wafer, and compares it with the position of the predefined theoretical wafer straight edge to determine whether the actual direction of the wafer straight edge coincides with or is parallel to the predefined direction. If it does not meet the requirements, the deviation information is sent to the adjustment mechanism; S6, after receiving the wafer straight edge position deviation information sent by the CCD positioning system, the adjustment mechanism (50) starts the hollow rotating platform to rotate at a small angle to adjust the wafer straight edge position; S7, a CCD image collector B (401) continues to collect the wafer straight edge position information, analyzes and determines whether the actual direction of the wafer straight edge coincides with or is parallel to the predefined direction, and repeats S6 until the actual direction of the wafer straight edge coincides with or is parallel to the predefined direction; S8, three CCD image collectors B (401) simultaneously collect wafer arc position information, calculate the actual wafer center position, and send the wafer center position to the laser marking system; S9, the P-axis linear module (501) of the adjustment mechanism (50) moves the wafer from the CCD positioning station to the laser marking station; S10, after the wafer is moved to the laser marking station, the laser marking system (60) performs mirror deviation correction according to the actual wafer center position sent by the CCD positioning system, executes the laser marking action, and outputs the marking content to the correct position on the wafer; S11, after the laser marking is completed, the handling system (30) moves the vacuum suction fingers (305) to the marking station to take the wafer, the second vacuum generator (707) breaks the vacuum, the wafer is separated from the wafer loading platform (503), and at the same time, the first vacuum generator (706) is vacuumized, the vacuum suction fingers (305) are adsorbed, and then the handling system moves the wafer from the marking station to the current wafer taking layer in the wafer magazine (101); S12, according to the wafer-lacking layer information recorded by the CCD recognition system, automatically skip the wafer-lacking layer, sequentially take the wafer of the next layer, and repeat steps 3 to 12 until all wafer marking is completed; S13, the handling system returns to the safe position; S14, the wafer magazine (101) and the completed wafer marking are removed from the magazine jig plate (102) of the wafer loading and unloading station.

Images