Wafer edge front surface visual inspection mechanism

Abstract

The utility model discloses a kind of wafer edge front visual inspection mechanism, including mounting base plate, fixedly equipped with XY axis moving mechanism on mounting base plate, fixedly equipped with lifting material receiving mechanism and rotating material receiving mechanism on XY axis moving mechanism, and visual inspection mechanism is fixedly equipped with on the one side of rotating material receiving mechanism of mounting base plate;Lifting material receiving mechanism includes drive electric cylinder, column seat and first vacuum platform, drive electric cylinder includes slide and first guide rail, slide top and column seat are connected, a plurality of first column are equipped on column seat, first column top and first vacuum platform are connected, drive electric cylinder output end drive slide linearly along first guide rail, to drive first vacuum platform lifting, to contactless adsorption wafer and place wafer on rotating material receiving mechanism, XY axis moving mechanism drives wafer on rotating material receiving mechanism to move, to adapt the detection range of visual inspection mechanism, the utility model, with the characteristics that wafer damage risk is reduced in short clamping contact time.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor inspection equipment technology, specifically a wafer edge front visual inspection mechanism. Background Technology

[0002] In the semiconductor wafer manufacturing and inspection process, defects such as cracks, chipping, and scratches on the front edge of the wafer directly determine the wafer yield and the reliability of subsequent chip manufacturing processes. Therefore, edge vision inspection has become an important part of core quality control. The contact method and contact duration during the wafer loading process from transfer to the inspection platform have a particularly significant impact on the wafer structure.

[0003] A published Chinese patent, publication number CN215953960U, discloses a correction device for wafer inspection, including a mounting base plate, multiple XYθ axis guide modules, a driving device, and a stage assembly. The stage assembly is rotatably mounted on the mounting base plate. The multiple XYθ axis guide modules are disposed between the mounting base plate and the stage assembly and are evenly distributed on the circle where the rotation axis of the stage assembly is located. The XYθ axis guide module includes, from bottom to top, a guide module base plate, an X-axis guide module, a Y-axis guide module, and a rotation module. The guide module base plate is fixed to the mounting base plate, the rotation module is fixedly connected to the stage assembly, and the driving device is connected to the X-axis guide module of one of the XYθ axis guide modules to drive the stage assembly to rotate. The platform assembly provided by the disclosed patent lacks dynamic adjustment capability in conjunction with the detection camera, and cannot flexibly adapt to the camera's field of view according to the actual placement position of the wafer. As a result, during the process of the unloading robot placing the wafer onto the platform assembly, the unloading robot needs to slowly adjust the vertical height and horizontal position of the wafer to adapt to the camera's field of view. During this process, the grippers need to continuously apply clamping force to prevent the wafer from falling off. Excessive clamping and adjustment time may cause indentations on the wafer edge, or even cause the wafer to deform or break.

[0004] Therefore, it is essential to design a wafer edge front visual inspection mechanism that reduces the risk of wafer damage by shortening the clamping contact time. Utility Model Content

[0005] The purpose of this invention is to provide a wafer edge front visual inspection mechanism to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a wafer edge front visual inspection mechanism, including a mounting base plate, an XY axis moving mechanism fixed on the mounting base plate, a lifting receiving mechanism and a rotating receiving mechanism fixed on the XY axis moving mechanism, and a visual inspection mechanism fixed on one side of the rotating receiving mechanism on the mounting base plate. The lifting and receiving mechanism includes a drive cylinder, a column base, and a first vacuum platform. The drive cylinder includes a slide and a first guide rail. The top of the slide is connected to the column base, and the column base is provided with multiple first columns. The top of the first columns is connected to the first vacuum platform. The output end of the drive cylinder drives the slide to slide linearly along the first guide rail, thereby driving the first vacuum platform to lift and lower, so as to non-contactly adsorb the wafer and place the wafer on the rotary receiving mechanism. The XY axis moving mechanism drives the wafer on the rotary receiving mechanism to move to adapt to the detection range of the vision inspection mechanism.

[0007] In one embodiment of this utility model, the XY axis moving mechanism includes an X-axis motor and a Y-axis motor. The output ends of the X-axis motor and the Y-axis motor are each provided with a lead screw. A moving seat is provided on the lead screw. A lower moving plate and an upper moving plate are respectively connected to one side of the moving seat of the X-axis motor and the Y-axis motor. The Y-axis motor is mounted on one side of the lower moving plate. A second guide rail is fixedly provided on both the mounting base plate and the lower moving plate. A slider that slides with the second guide rail is provided at the bottom of both the lower moving plate and the upper moving plate.

[0008] In one embodiment of this utility model, the rotating receiving mechanism includes a first mounting frame, a stepper motor, a driving pulley, a driven pulley, a transmission belt, a hollow rotating disk, second columns, and a second vacuum platform. The first mounting frame is fixed to the top of the upper moving plate. The stepper motor is fixed to one side of the upper moving plate via a bracket, and the output end of the stepper motor is connected to the driving pulley. The driven pulley is located below the first mounting frame and is connected to the driving pulley via the transmission belt. The driven pulley is connected to the hollow rotating disk. A plurality of second columns are equidistantly arranged in a ring around the top surface of the hollow rotating disk, and the other end of the second column is connected to the second vacuum platform.

[0009] In one embodiment of the present invention, the visual inspection mechanism includes a second mounting frame, an inspection camera, and a light source. The second mounting frame is fixed to one side of the mounting base plate. The inspection camera and the light source are both mounted on the second mounting frame, and the light source is located below the inspection camera.

[0010] In one embodiment of this utility model, photoelectric sensors are provided on the lower moving plate, the upper moving plate, and the hollow rotating disk.

[0011] In one embodiment of the present invention, the first mounting bracket is provided with a cover above the stepper motor.

[0012] Compared with the prior art, the beneficial effects achieved by this utility model are: (1) By setting up a lifting and receiving mechanism, the first vacuum platform in the lifting and receiving mechanism can achieve non-contact fixing of the wafer through vacuum adsorption. With the lifting and lowering motion of the sliding block driven by the drive cylinder, it can receive the wafer placed by the unloading robot and smoothly descend to the same height as the second vacuum platform of the rotating receiving mechanism before completing the wafer transfer. Compared with the traditional method of directly clamping and unloading by the robot, this structure avoids long-term contact between the robot and the wafer, reduces problems such as wafer deformation and edge indentation caused by clamping force, and avoids the risk of collision between the wafer and the platform when directly unloading, effectively improving the wafer transfer yield and significantly reducing the risk of wafer damage. (2) By setting up an XY axis moving mechanism, the XY axis moving mechanism drives the lower moving plate and the upper moving plate to slide along the second guide rail through the X-axis motor and the Y-axis motor respectively. This can drive the rotating receiving mechanism and the wafer above to achieve precise displacement in the X and Y directions. It can dynamically adjust according to the actual placement position of the wafer, make up for the feeding deviation, and ensure that the edge of the wafer is always within the best field of view and focus range of the detection camera in the vision inspection mechanism, avoiding missed detection and false detection due to position offset. Attached Figure Description

[0013] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structural composition of this utility model; Figure 2 This is a schematic diagram of the lifting and receiving mechanism of this utility model; Figure 3 This is a schematic diagram of the XY axis moving mechanism of this utility model; Figure 4 This is a schematic diagram of the rotating receiving mechanism of this utility model; In the diagram: 10. Mounting base plate; 20. XY axis moving mechanism; 21. X-axis motor; 22. Y-axis motor; 23. Lead screw; 24. Moving seat; 25. Lower moving plate; 26. Upper moving plate; 27. Second guide rail; 28. Slider; 30. Lifting and receiving mechanism; 31. Drive cylinder; 311. Slide seat; 312. First guide rail; 32. Column base; 321. First column; 33. First vacuum platform; 40. Rotary receiving mechanism; 41. First mounting frame; 411. Cover; 42. Stepper motor; 43. Driving pulley; 44. Driven pulley; 45. Transmission belt; 46. Hollow rotary disk; 47. Second column; 48. Second vacuum platform; 50. Vision inspection mechanism; 51. Second mounting frame; 52. Inspection camera; 53. Light source; 60. Photoelectric sensor. Detailed Implementation

[0014] To enable those skilled in the art to better understand the present invention, the solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0015] This utility model provides a technical solution: a wafer edge front visual inspection mechanism, including a mounting base plate 10, an XY axis moving mechanism 20 fixed on the mounting base plate 10, a lifting receiving mechanism 30 and a rotating receiving mechanism 40 fixed on the XY axis moving mechanism 20, and a visual inspection mechanism 50 fixed on one side of the rotating receiving mechanism 40. The XY axis moving mechanism 20, the lifting receiving mechanism 30, the rotating receiving mechanism 40 and the visual inspection mechanism 50 are integrated on the same mounting base plate 10, forming a closed-loop process of receiving, transferring, positioning and inspection, without the need for additional independent equipment, avoiding signal delay and positioning deviation between multiple devices, and significantly shortening the overall time from wafer receiving to inspection. The lifting and receiving mechanism 30 includes a drive cylinder 31, a column base 32, and a first vacuum platform 33. The drive cylinder 31 includes a slide 311 and a first guide rail 312. The top of the slide 311 is connected to the column base 32. The column base 32 is provided with multiple first columns 321. The top of the first columns 321 is connected to the first vacuum platform 33. The multiple first columns 321 support the first vacuum platform 33 in a distributed manner. Compared with a single support structure, this can effectively distribute the weight of the wafer and prevent the platform from tilting or deforming due to uneven force. The output of the drive cylinder 31 drives the slide 311 to slide linearly along the first guide rail 312, thereby driving the first vacuum platform 33 to rise and fall, so as to non-contactly adsorb the wafer and place the wafer on the rotary receiving mechanism 40. The XY axis moving mechanism 20 drives the wafer on the rotary receiving mechanism 40 to move to match the detection range of the vision inspection mechanism 50. The lifting receiving mechanism 30 uses the first vacuum platform 33 as the wafer carrier and achieves non-contact fixing of the wafer through vacuum adsorption, avoiding the edge indentation and wafer deformation problems caused by traditional mechanical grippers. At the same time, the drive cylinder 31 drives the slide 311 to rise and fall smoothly along the first guide rail 312, which can precisely control the lifting speed and height of the first vacuum platform 33. When receiving the wafer, it rises to the height that matches the unloading robot, and slowly descends to be flush with the second vacuum platform 48 during transfer. There is no rigid collision between the wafer and the platform throughout the process, which effectively avoids the risk of breakage and scratches in the transfer of thin and large wafers and significantly improves the wafer transfer yield.

[0016] The XY axis moving mechanism 20 includes an X-axis motor 21 and a Y-axis motor 22. Both the X-axis motor 21 and the Y-axis motor 22 have lead screws 23 at their output ends. A movable seat 24 is mounted on the lead screw 23. A lower movable plate 25 and an upper movable plate 26 are respectively connected to one side of the movable seat 24 of the X-axis motor 21 and the Y-axis motor 22. The Y-axis motor 22 is mounted on one side of the lower movable plate 25. A second guide rail 27 is fixed on both the mounting base 10 and the lower movable plate 25. A slider 28 that slides with the second guide rail 27 is provided at the bottom of both the lower movable plate 25 and the upper movable plate 26. The X-axis motor 21 and the Y-axis motor 22... The axial motors 22 independently control the movement of the lower moving plate 25 and the upper moving plate 26. When it is necessary to adjust the position of the wafer along the X direction, only the X-axis motor 21 needs to be driven, which drives the moving seat 24 and the lower moving plate 25 to slide along the second guide rail 27 on the mounting base plate 10 via the lead screw 23. When it is necessary to adjust the position of the wafer along the Y direction, the Y-axis motor 22 can be driven separately, which drives the moving seat 24 and the upper moving plate 26 to slide along the second guide rail 27 on the lower moving plate 25, so as to accurately adjust the edge of the wafer to the optimal shooting range of the vision inspection mechanism 50 and avoid missed or incorrect inspections due to positional deviation.

[0017] The rotary receiving mechanism 40 includes a first mounting frame 41, a stepper motor 42, a driving pulley 43, a driven pulley 44, a transmission belt 45, a hollow rotary disk 46, a second column 47, and a second vacuum platform 48. The first mounting frame 41 is fixed to the top of the upper movable plate 26. The stepper motor 42 is fixed to one side of the upper movable plate 26 via a bracket, and the output end of the stepper motor 42 is connected to the driving pulley 43. The driven pulley 44 is located below the first mounting frame 41 and is connected to the driving pulley 43 via the transmission belt 45. The driven pulley 44 is connected to the hollow rotary disk 46. The disk 46 is connected, and multiple second columns 47 are equidistantly arranged on the top surface of the hollow rotating disk 46. The other end of the second column 47 is connected to the second vacuum platform 48. The stepper motor 42 forms a flexible transmission structure through the active pulley 43, the transmission belt 45 and the driven pulley 44. Compared with rigid gear transmission, belt transmission can effectively buffer the vibration when the motor is running, and avoid the vibration from being transmitted to the hollow rotating disk 46 and the second vacuum platform 48 above it. This ensures that there is no obvious shaking during the rotation of the wafer, laying the foundation for the visual inspection mechanism 50 to collect clear and unblurred edge images.

[0018] The visual inspection mechanism 50 includes a second mounting bracket 51, an inspection camera 52, and a light source 53. The second mounting bracket 51 is fixed to one side of the mounting base plate 10. The inspection camera 52 and the light source 53 are both mounted on the second mounting bracket 51, and the light source 53 is located below the inspection camera 52. The light source 53, located below the inspection camera 52, can directly provide directional and uniform illumination to the wafer edge inspection area, effectively eliminating the interference of wafer surface reflection or shadow on imaging. Especially for the small depressions at the wafer edge, the illumination of the light source 53 can enhance the contrast between the defect area and the normal area, allowing the inspection camera 52 to capture defect details more clearly.

[0019] Photoelectric sensors 60 are provided on the lower moving plate 25, the upper moving plate 26, and the hollow rotating disk 46. The photoelectric sensors 60 on the lower moving plate 25 and the upper moving plate 26 can capture the sliding position of the two moving plates along the second guide rail 27 in real time, avoiding exceeding the preset sliding stroke. The photoelectric sensor 60 on the hollow rotating disk 46 can monitor the rotation angle in real time, ensuring that the wafer edge can achieve 360° scanning without dead angles, avoiding detection blind spots caused by insufficient rotation angle. The first mounting bracket 41 is provided with a cover 411 above the stepper motor 42. The cover 411 covers the outside of the stepper motor 42, which can effectively isolate dust and impurities in the detection environment and prevent debris from getting stuck in the meshing gap between the pulley and the belt, causing transmission jamming.

[0020] Working principle: The unloading robot transfers the wafer to be tested to the first vacuum platform 33 of the lifting and receiving mechanism 30. At this time, the drive cylinder 31 receives the control system command and drives the slide 311 to slide smoothly upward along the first guide rail 312, which drives the column base 32 and the first vacuum platform 33 at the top to rise to the receiving height that is compatible with the unloading robot. The first vacuum platform 33 starts vacuum adsorption of the wafer, and the unloading robot releases the wafer. The wafer is adsorbed and fixed on the surface of the first vacuum platform 33 in a non-contact state. After the material is received, the drive cylinder 31 drives the slide 311 to slide down along the first guide rail 312 again, causing the first vacuum platform 33 and the wafer to slowly descend until the first vacuum platform 33 is level with the second vacuum platform 48 of the rotating material receiving mechanism 40. At this time, the first vacuum platform 33 closes the vacuum adsorption, and the second vacuum platform 48 starts the vacuum adsorption. The wafer is smoothly transferred to the surface of the second vacuum platform 48 in a non-contact and non-collision state, completing the transfer connection. The control system dynamically adjusts the wafer's actual placement position. If adjustment is required along the X-axis, the X-axis motor 21 is started, which drives the moving base 24 and the lower moving plate 25 to slide along the second guide rail 27 on the mounting base plate 10 via the lead screw 23 until the lower moving plate 25 reaches the preset X-axis position. If adjustment is required along the Y-axis, the Y-axis motor 22 is started, which drives the moving base 24 and the upper moving plate 26 to slide along the second guide rail 27 on the lower moving plate 25 via the lead screw 23. During this process, the photoelectric sensors 60 on the lower moving plate 25 and the upper moving plate 26 capture the movement position in real time to avoid overtravel collisions. After the position adjustment is completed, the stepper motor 42 of the rotary receiving mechanism 40 starts, and drives the driven pulley 44 to rotate through the active pulley 43 and the transmission belt 45. This drives the hollow rotary disk 46 connected to the driven pulley 44 to rotate at a constant speed. The hollow rotary disk 46 drives the second vacuum platform 48 and the wafer to rotate synchronously and at a constant speed through multiple second columns 47. At the same time, the photoelectric sensor 60 on the hollow rotary disk 46 monitors the rotation angle in real time to ensure that the wafer can achieve 360° scanning without dead angles. If a suspected defect is detected, the stepper motor 42 can be triggered to pause or rotate in reverse for secondary verification. During the wafer rotation scanning process, the vision inspection mechanism 50 starts working simultaneously, the light source 53 on the second mounting bracket 51 is turned on, providing directional and uniform illumination to the wafer edge inspection area, the inspection camera 52 is aligned with the wafer edge, and the edge image during the rotation process is acquired in real time. The image data is then transmitted to the back-end analysis system. The analysis system automatically identifies and marks the defect information of the wafer edge by comparing it with the defect feature library, thus completing the inspection process.

[0021] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation or specific orientation structure and operation, and therefore should not be construed as a limitation of this utility model; the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In addition, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0022] In the description of this utility model, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this utility model, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, those skilled in the art can combine different embodiments or examples and features of different embodiments or examples described in this utility model without contradiction.

[0023] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wafer edge front visual inspection mechanism, comprising a mounting base plate (10), wherein an XY axis moving mechanism (20) is fixedly mounted on the mounting base plate (10), wherein a lifting receiving mechanism (30) and a rotating receiving mechanism (40) are fixedly mounted on the XY axis moving mechanism (20), and a visual inspection mechanism (50) is fixedly mounted on one side of the rotating receiving mechanism (40) on the mounting base plate (10). Its features are: The lifting and receiving mechanism (30) includes a drive cylinder (31), a column base (32), and a first vacuum platform (33). The drive cylinder (31) includes a slide (311) and a first guide rail (312). The top of the slide (311) is connected to the column base (32). The column base (32) is provided with a plurality of first columns (321). The top of the first columns (321) is connected to the first vacuum platform (33). The output end of the drive cylinder (31) drives the slide (311) to slide linearly along the first guide rail (312), thereby driving the first vacuum platform (33) to lift and lower, so as to non-contactly adsorb the wafer and place the wafer on the rotating receiving mechanism (40). The XY axis moving mechanism (20) drives the wafer on the rotating receiving mechanism (40) to move to adapt to the detection range of the vision inspection mechanism (50).

2. The wafer edge front visual inspection mechanism according to claim 1, characterized in that: The XY axis moving mechanism (20) includes an X-axis motor (21) and a Y-axis motor (22). Both the X-axis motor (21) and the Y-axis motor (22) have lead screws (23) at their output ends. The lead screws (23) have moving seats (24). The moving seats (24) of the X-axis motor (21) and the Y-axis motor (22) are respectively connected to a lower moving plate (25) and an upper moving plate (26). The Y-axis motor (22) is mounted on one side of the lower moving plate (25). The mounting base plate (10) and the lower moving plate (25) are both fixed with second guide rails (27). The bottom of the lower moving plate (25) and the upper moving plate (26) are both provided with sliders (28) that slide with the second guide rails (27).

3. The wafer edge front visual inspection mechanism according to claim 2, characterized in that: The rotating receiving mechanism (40) includes a first mounting frame (41), a stepper motor (42), a driving pulley (43), a driven pulley (44), a transmission belt (45), a hollow rotating disk (46), a second column (47), and a second vacuum platform (48). The first mounting frame (41) is fixed on the top of the upper moving plate (26). The stepper motor (42) is fixed on one side of the upper moving plate (26) through a bracket, and the output end of the stepper motor (42) is connected to the driving pulley (43). The driven pulley (44) is located below the first mounting frame (41) and is connected to the driving pulley (43) through the transmission belt (45). The driven pulley (44) is connected to the hollow rotating disk (46). A plurality of second columns (47) are equidistantly arranged in a ring on the top surface of the hollow rotating disk (46), and the other end of the second column (47) is connected to the second vacuum platform (48).

4. The wafer edge front visual inspection mechanism according to claim 1, characterized in that: The visual inspection mechanism (50) includes a second mounting bracket (51), an inspection camera (52) and a light source (53). The second mounting bracket (51) is fixed on one side of the mounting base plate (10). The inspection camera (52) and the light source (53) are both mounted on the second mounting bracket (51), and the light source (53) is located below the inspection camera (52).

5. A wafer edge front visual inspection mechanism according to claim 2 or 3, characterized in that: Photoelectric sensors (60) are provided on the lower moving plate (25), the upper moving plate (26), and the hollow rotating disk (46).

6. The wafer edge front visual inspection mechanism according to claim 3, characterized in that: The first mounting bracket (41) has a cover (411) above the stepper motor (42).

Images