Wafer visual inspection device

Abstract

The utility model discloses a wafer visual inspection device, which comprises a working table, and a mechanical arm, a wafer bin group and a turnover device which are arranged on the working table, the wafer bin group and the turnover device are positioned on an operation path of the mechanical arm, and the mechanical arm and the turnover device are connected with a controller; the wafer bin group comprises a plurality of wafer bins, each wafer bin is used for storing wafers in different states, and the wafers are arranged at intervals from top to bottom; a clamping mechanism is arranged on the overturning device and is used for fixing and overturning a wafer to be detected; the suction cup is connected with the mechanical arm and is used for adsorbing a wafer; according to the device, automatic transfer of the wafer in the visual inspection process is achieved, contact between workers and the wafer is avoided, damage to the wafer in the transfer process is avoided, and meanwhile the inspection efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of wafer manufacturing, in particular to a wafer visual inspection device. Background Art

[0002] Wafer inspection and sorting is an important part of the semiconductor manufacturing process, which directly affects the quality and output of chips. Wafers need to go through multiple steps in the manufacturing process, including lithography, etching, ion implantation, chemical vapor deposition, etc. Each step may affect the performance and quality of the wafer. Therefore, it is crucial to accurately inspect and sort wafers.

[0003] Manual inspection of wafers takes a lot of time because each wafer needs to be handled individually, which limits production speed and increases production costs. Secondly, during the inspection process, vacuum pens or suction cups are used to pick up and place wafers. Wafers are stacked in multiple layers in the storage bin. When using vacuum pens to pick up wafers, they are prone to collision with the storage bin, causing physical damage to the wafers and affecting product quality. Manual inspection and handling of wafers is a labor-intensive job. Long-term operation may cause operator fatigue, further increasing the error rate. Utility Model Content

[0004] In view of the problems existing in the prior art, the utility model provides a wafer visual inspection device which adopts a mechanical arm to automatically absorb the wafer to achieve high-efficiency inspection of the wafer.

[0005] The utility model is realized by the following technical solutions:

[0006] A wafer visual inspection device comprises a workbench, and a mechanical arm, a wafer bin group and a flipping device arranged on the workbench, wherein the wafer bin group and the flipping device are located on a running path of the mechanical arm, and the mechanical arm and the flipping device are connected to a controller;

[0007] The wafer bin group includes a plurality of wafer bins, each wafer bin is used to store wafers in different states, and the wafers are arranged at intervals from top to bottom;

[0008] The flipping device is provided with a clamping mechanism for fixing and flipping the wafer to be inspected;

[0009] The suction cup is connected to the robot arm, and is used to adsorb the wafer.

[0010] Preferably, the multiple wafer bins are arranged in sequence along the edge of the workbench and are disposed opposite to the robotic arm.

[0011] Preferably, a plurality of compartments are arranged at intervals from top to bottom in the wafer warehouse, and the compartments include two card slots located at the same height, the two card slots are respectively arranged on the inner walls of the two vertical walls of the wafer warehouse, and the opening sides of the card slots are arranged opposite to each other, and the card slots pass through the front end of the wafer warehouse.

[0012] Preferably, a limiting structure is provided at the rear end of the card slot.

[0013] Preferably, an image acquisition device is provided at the front end of the wafer bin group, a light shielding plate is provided at the rear end of the wafer bin group, and the image acquisition device is connected to a controller.

[0014] Preferably, the flipping device comprises a fixing seat and a servo motor;

[0015] The lower end of the fixing seat is fixed on the table top of the workbench, the servo motor is installed on the upper end of the fixing seat, the clamping mechanism is connected to the output shaft of the servo motor, the clamping mechanism is close to one side of the mechanical arm, and a card slot for fixing the wafer is arranged on the clamping mechanism.

[0016] Preferably, the clamping mechanism is a U-shaped structure, the closed end of the clamping mechanism is connected to the servo motor, the open end of the clamping mechanism is located on the side close to the robotic arm, and a horizontal slot is provided on the inner wall of the U-shaped structure of the clamping mechanism, and part of the edge of the wafer is overlapped in the slot.

[0017] Preferably, a position detection device is provided on the fixing seat for detecting the flipping angle of the wafer.

[0018] Preferably, the position detection device is a photoelectric switch.

[0019] Preferably, the suction cup comprises a suction cup body, an air cavity and a fixed arm;

[0020] The plurality of fixed arms are arranged at the edge of the suction cup base and distributed circumferentially, and the ends of the fixed arms are provided with raised limiting blocks for limiting the edge of the wafer;

[0021] An air channel is arranged in the suction cup base, an air outlet is arranged in the air cavity, the air channel is connected with the air outlet, the air flow from the air outlet flows along the tangential direction of the inner wall of the air cavity and forms a swirling vortex in the air cavity.

[0022] Compared with the prior art, the utility model has the following beneficial technical effects:

[0023] The utility model provides a wafer visual inspection device, which arranges a wafer bin, an image acquisition device, a flipping device, a mechanical arm and a suction cup connected to the mechanical arm on a workbench, a controller connects the flipping device and the signal end of the mechanical arm, the image acquisition device acquires the image of the wafer bin, and determines the position of the wafer in combination with the image recognition and analysis method, the mechanical arm operates the suction cup to move, accurately transfers the wafer between the workstations, and simultaneously uses the flipping device to flip the wafer to achieve visual inspection of the two walls of the wafer. The device realizes automatic transportation of the wafer during the visual inspection process, avoids contact between the staff and the wafer, solves the damage to the wafer during the operation process, and improves the inspection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the wafer visual inspection device of the utility model;

[0025] Figure 2 This is a schematic diagram of the structure of the turning device of the utility model;

[0026] Figure 3 This is a schematic diagram of the structure of the servo motor of the utility model;

[0027] Figure 4 This is a schematic diagram of the structure of the wafer clamp of the utility model;

[0028] Figure 5 This is a schematic diagram of the structure of the wafer bin group of the utility model;

[0029] Figure 6 This is a schematic diagram of the structure of the wafer bin of the utility model;

[0030] Figure 7 This is a schematic diagram of the structure of the mechanical arm of the utility model;

[0031] Figure 8 It is a structural schematic diagram of the suction cup of the utility model.

[0032] In the figure: 1. workbench; 2. robotic arm; 3. wafer bin assembly; 4. flip device; 5. controller; 6. wafer; 7. suction cup; 41. servo motor; 42. wafer clamp; 43. fixing seat; 44. photoelectric switch; 45. detection board; 46. adapter; 47. card slot; 31. shading plate; 32. wafer bin; 33. bin grid; 71. air cavity; 72. fixing arm; 73. air inlet; 74. baffle. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings, which are intended to explain the present invention rather than to limit it.

[0034] See also Figure 1-8A wafer visual inspection device includes a workbench 1, and a robot arm 2, a wafer bin group 3 and a flip device 4 arranged on the workbench, the movable end of the robot arm is connected to a suction cup 7, the wafer bin group 3 and the flip device 4 are located on the operation path of the robot arm, the wafer bin group 3 is used to store wafers 6, the robot arm 2 and the flip device 4 are connected to a controller 5, and the controller is used to control the operation path of the robot arm 2 and the flip angle of the flip device 4 to the wafer.

[0035] See also Figure 5 The wafer bin group 3 includes multiple wafer bins, which are arranged on the workbench at intervals along one side edge of the workbench 1 and face the robotic arm 2. The multiple wafer bins are distinguished according to the types of wafers placed. For example, the first wafer bin is a wafer bin to be inspected, that is, the wafer bin is used to place wafers to be inspected, the second wafer bin is a wafer bin for normal wafers, that is, wafers in normal state after inspection, and the third wafer bin is a wafer bin for abnormal wafers, that is, wafers in abnormal state after inspection, and the wafers are contaminated, scratched, defective, etc.

[0036] In the present embodiment, three wafer bins are provided, and more wafer bins may be provided to classify and store wafers in normal state by model.

[0037] See also Figure 6 The wafer bin 32 is a cavity structure, and the front end of the wafer bin 32 is an open structure, that is, one end facing the robotic arm. Bins 33 are arranged on both vertical side walls of the wafer bin, and multiple bins are arranged at intervals from top to bottom. The distance between the bottom bin and the bottom surface is greater than the overall thickness of the suction cup 7, which can ensure that the suction cup 7 extends to the bottom of the bottom wafer; the bin includes two card slots at the same height, and the opening sides of the two card slots are arranged opposite to each other. At the same time, the front end of the card slot is also an open side. The distance between the inner edges of the two card slots is less than the diameter of the wafer. When the wafer is located in the bin, the edge of the wafer overlaps in the card slot.

[0038] The front end of the bin is an open end, and the rear end is an inwardly contracted arc structure, which limits the position of the wafer in the bin. Figure 6 The front part of the card slot is a straight line segment, the thickness is an arc-shaped structure and matches the wafer, and the front and rear ends of the wafer bin 32 are both open, which is convenient for observing the position of the suction cup in the wafer bin.

[0039] A shading plate 31 is provided at the rear end of the wafer bin to improve the quality of the collected image. A camera (not shown in the figure) is provided at the front end of the wafer bin to obtain pictures of the wafers in the wafer bin. The controller determines the number and position of the wafers in the wafer bin based on the collected photos and in combination with the image recognition method. For example, based on the edge information detection method, a contour matching algorithm is used to identify and locate objects in the image. This method searches for edge contours of objects and matches these contours with known templates to determine the number of wafers. Since the number of wafers is taken and placed in a certain order, when the number of wafers is determined, the position of the space and the position of the wafer can be determined; or an image detection method. In this embodiment, a computer vision image analysis method is adopted. The camera captures the real-time picture of the wafer bin, and then analyzes the wafers through computer vision to calculate their positions and deviations. The controller adjusts the corresponding posture of the robotic arm to perform the wafer taking operation.

[0040] See also Figure 2 The flipping device 4 includes a fixing seat 43, a servo motor 41, a wafer clamp 42 and a position detection device.

[0041] The lower end of the fixing seat is fixed on the table top of the workbench and is located at one end of the wafer chamber group. The servo motor 41 is installed on the rear side of the upper end of the fixing seat 43, that is, the side away from the robotic arm. The wafer clamp 42 is connected to the output shaft of the servo motor through the adapter 46. The wafer clamp 42 is close to the side of the robotic arm, and the suction cup is driven to flip by the servo motor.

[0042] See also Figure 3 The wafer clamp 42 is a U-shaped structure, and its closed end is connected to one end of the adapter, and the other end of the adapter is connected to the servo motor. The open end of the wafer clamp 42 is located on the side close to the robotic arm. A horizontal slot is provided on the inner wall of the U-shaped structure of the wafer clamp 42. The structure of the slot 47 is the same as that of the bin. Part of the edge of the wafer is overlapped in the slot, so that the wafer is suspended in the wafer clamp 42. The servo motor drives the wafer clamp to rotate, and the staff visually detects whether the wafer has defects. When the wafer has defects, the instruction is input in the display of the controller, and the robotic arm places the wafer in the corresponding wafer bin.

[0043] The position detection device is arranged on the fixed seat, and is used to detect whether the flip angle of the wafer is in a horizontal state. The position detection device includes a slot-type photoelectric switch 44 and a detection plate 45. The photoelectric switch 44 is fixed at the front end of the fixed seat and is located below the adapter seat. One end of the detection plate 45 is connected to the adapter seat, and the adapter seat drives the detection plate to rotate synchronously. When the detection plate is located in the groove of the photoelectric switch 44, the servo motor stops rotating. Position detection devices can also be arranged above and below the adapter seat. The servo motor detects once every 180° rotation to realize positioning detection on both sides of the wafer. A fill light is also arranged on the workbench, and the emitted light source is used to illuminate the wafer to improve the visual illumination during the wafer detection process.

[0044] See also Figure 7 The fixed end of the robotic arm is connected to the workbench, and the moving end of the robotic arm is connected to the suction cup. The suction cup is located below the moving end of the robotic arm. The robotic arm drives the suction cup to move horizontally and up and down.

[0045] See also Figure 8 The suction cup includes a suction cup body, an air cavity 71 , a fixed arm 72 and a baffle 74 .

[0046] The multiple fixed arms 72 are arranged on the edge of the suction cup base and distributed circumferentially, and a raised limit block is provided at the end of the fixed arm for limiting the edge of the wafer. An air duct is arranged in the suction cup base, and the air inlet of the air duct is arranged on the connecting arm of the suction cup body, and the connecting arm is connected to the mechanical arm. In this embodiment, four suction cups are distributed circumferentially on the top surface of the suction cup base and form a convex ring structure. An air outlet is arranged in the air cavity, and the inner wall of the air cavity is a conical surface, and the air flow of the air outlet flows tangentially along the inner wall of the air cavity and forms a swirling vortex in the air cavity. The air flow rotates upward along the conical side wall of the air cavity and forms an air film between the base and the top surface of the conical ring. The wafer is suspended on the top of the base through the air film. At the same time, the vortex forms a negative pressure area in the center of the air cavity, which forms an adsorption effect on the wafer, so that the wafer is adsorbed on the top of the suction cup base and forms an air film between the suction cup base, thereby realizing non-contact transfer of the wafer.

[0047] The following is a detailed description of the method for using the above-mentioned wafer visual inspection device.

[0048] First, move the full wafer bin to the workbench and fix it, that is, place a wafer in each bin of the wafer bin, and the camera acquires the image of the wafer bin and the position of the bottom wafer. At the same time, the operator inputs the instruction to take the wafer in the display of the controller, and the robot arm extends the suction cup to the lower part of the bottom wafer of the wafer bin, and then moves upward so that the wafer is located between multiple fixed arms. Then the robot arm controls the suction cup to move horizontally and separate from the wafer bin. At this time, the wafer is suspended on the suction cup, and the robot arm moves the suction cup to the flipping device, and inserts the deviation of the wafer into the card slot. The suction cup and the wafer are Separated, the wafer is fixed on the flipping device, the servo motor rotates to achieve 180° flipping of the wafer, the staff conducts visual inspection on both sides of the wafer, enters the corresponding storage instruction in the display of the controller according to the inspection result, and the robotic arm repeats the above action to insert the wafer into the corresponding wafer bin. It should be noted that during the process of inserting the wafer into the wafer bin, the wafers are inserted from top to bottom in sequence. Through the above process, the automatic transportation of the wafer during the visual inspection process is realized, the contact between the staff and the wafer is avoided, the damage to the wafer during the operation process is solved, and the inspection efficiency is improved.

[0049] The above content is only for explaining the technical idea of ​​the utility model, and cannot be used to limit the protection scope of the utility model. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the utility model shall fall within the protection scope of the claims of the utility model.

Claims

1. A wafer visual inspection device, characterized in that: It includes a workbench, and a mechanical arm, a wafer bin group and a flipping device arranged on the workbench, wherein the wafer bin group and the flipping device are located on the operation path of the mechanical arm, and the mechanical arm and the flipping device are connected to a controller; The wafer bin group includes a plurality of wafer bins, each wafer bin is used to store wafers in different states, and the wafers are arranged at intervals from top to bottom; The flipping device is provided with a clamping mechanism for fixing and flipping the wafer to be inspected; The mechanical arm is connected to a suction cup, and the suction cup is used to adsorb the wafer.

2. A wafer visual inspection device according to claim 1, characterized in that: The multiple wafer bins are arranged in sequence along the edge of the workbench and are arranged opposite to the robot arm.

3. A wafer visual inspection device according to claim 1, characterized in that: A plurality of bins are arranged at intervals from top to bottom in the wafer bin, and the bins include two card slots located at the same height, the two card slots are respectively arranged on the inner walls of the two vertical walls of the wafer bin, and the opening sides of the card slots are arranged opposite to each other, and the card slots run through the front end of the wafer bin.

4. A wafer visual inspection device according to claim 3, characterized in that: A limiting structure is arranged at the rear end of the card slot.

5. The wafer visual inspection device according to claim 1, characterized in that: An image acquisition device is arranged at the front end of the wafer bin group, a light shielding plate is arranged at the rear end of the wafer bin group, and the image acquisition device is connected to a controller.

6. The wafer visual inspection device according to claim 1, characterized in that: The flipping device comprises a fixing seat and a servo motor; The lower end of the fixing seat is fixed on the table top of the workbench, the servo motor is installed on the upper end of the fixing seat, the clamping mechanism is connected to the output shaft of the servo motor, the clamping mechanism is close to one side of the mechanical arm, and a card slot for fixing the wafer is arranged on the clamping mechanism.

7. The wafer visual inspection device according to claim 6, characterized in that: The clamping mechanism is a U-shaped structure, the closed end of the clamping mechanism is connected to the servo motor, the open end of the clamping mechanism is located on the side close to the robotic arm, and a horizontal slot is provided on the inner wall of the U-shaped structure of the clamping mechanism, and part of the edge of the wafer is overlapped in the slot.

8. The wafer visual inspection device according to claim 6, characterized in that: The fixing seat is provided with a position detection device for detecting the flipping angle of the wafer.

9. The wafer visual inspection device according to claim 8, characterized in that: The position detection device is a photoelectric switch.

10. A wafer visual inspection device according to any one of claims 1 to 9, characterized in that: The suction cup comprises a suction cup body, an air cavity and a fixed arm; The plurality of fixed arms are arranged at the edge of the suction cup base and distributed circumferentially, and the ends of the fixed arms are provided with raised limiting blocks for limiting the edge of the wafer; An air channel is arranged in the suction cup base, an air outlet is arranged in the air cavity, the air channel is connected with the air outlet, the air flow from the air outlet flows along the tangential direction of the inner wall of the air cavity and forms a swirling vortex in the air cavity.

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