A wafer inspection device

Abstract

This utility model relates to the field of wafer defect detection technology, and in particular to a wafer inspection device. The device includes a housing with a wafer cassette placement area and a door. Inside the housing are a wafer moving mechanism, an edge-finding mechanism, an edge defect detection assembly, and a surface defect detection assembly. The wafer moving mechanism includes a robotic arm for gripping and picking up wafers. The robotic arm reciprocates between the door, the edge-finding mechanism, the edge defect detection assembly, and the surface defect detection assembly to transport wafers. The edge defect detection assembly includes a wafer carrying device and an edge detection device for detecting defects and morphology at wafer edges and notches. The surface detection assembly includes a surface detection device for detecting surface defects on the wafer surface. This utility model can complete the functions of surface defect detection and edge defect detection in one set of equipment, avoiding wafer contamination during transfer between different devices, while improving wafer inspection efficiency and saving equipment space.

Description

Technical Field

[0001] This utility model relates to the field of wafer defect detection technology, and in particular to a wafer inspection device. Background Technology

[0002] In the semiconductor manufacturing field, wafers serve as the carriers of integrated circuits, and their quality directly affects chip yield and reliability. Wafer defects generally include surface defects and edge defects: surface defects include particle contamination, scratches, pit residues, etc., and are diverse in type and small in size; wafer edge defects can not only cause wafer breakage, but also spread to the chip functional areas in subsequent photolithography, etching and other processes, directly reducing product yield. Therefore, detailed defect inspection of wafers is necessary.

[0003] Existing detection schemes usually have the following problems: (1) Due to the large difference between the wafer surface area and the defect size ratio, a single device is difficult to efficiently and effectively detect all defects on the wafer surface, which usually results in long detection time and low detection accuracy; (2) Multiple devices are used for multiple rounds of detection, but the wafer needs to be repositioned when it is transferred between multiple devices. The transfer process not only prolongs the detection time, but also makes it easy to have poor positioning accuracy and low detection quality. At the same time, the transfer process may also cause secondary contamination or damage to the wafer. Utility Model Content

[0004] The present invention aims to solve the above problems and provides a wafer inspection device, the technical solution of which is as follows: A wafer inspection device includes a housing with a wafer cassette placement area and a door. Inside the housing are a wafer moving mechanism, an edge-finding mechanism, an edge defect detection assembly, and a surface defect detection assembly. The wafer moving mechanism includes a robotic arm for gripping and picking up wafers. The robotic arm reciprocates between the door, the edge-finding mechanism, the edge defect detection assembly, and the surface defect detection assembly to transfer wafers. The edge defect detection assembly includes a wafer support device for supporting the wafers and an edge detection device for detecting defects and morphology at the wafer edges and notches. The surface inspection assembly includes a wafer support mechanism and a surface inspection device for detecting surface defects on the wafers. The wafer support mechanism carries the wafers to the shooting range of each camera in the surface inspection device.

[0005] Based on the above scheme, the edge detection device includes a circumferential detection unit and a marker detection unit. The circumferential detection unit is located on one side of the wafer and includes a circumferential camera and a light source for capturing images of the outer edge of the wafer. The number of circumferential cameras is multiple. The marker detection unit includes a marker camera and a light source for capturing images of the wafer notch shape. The number of marker cameras is multiple.

[0006] Based on the above scheme, the circumferential detection unit includes a first circumferential camera, a second circumferential camera, and a third circumferential camera. The first and third circumferential cameras are respectively arranged on the upper and lower sides of the wafer along the wafer axis and capture images of the wafer from the outer edge to a predetermined distance radially inward. The second circumferential camera is arranged radially along the wafer and is located on the center plane in the wafer thickness direction, capturing images of the outer edge of the wafer. The light source of the circumferential detection unit is a ring light source with its opening facing one side of the wafer, and the area of ​​the wafer to be photographed extends into the opening of the ring light source. The illumination range of the ring light source covers the shooting range of each camera in the circumferential detection unit.

[0007] Preferably, the marker detection unit includes a first marker camera, a second marker camera, a third marker camera, and a fourth marker camera. The first and fourth marker cameras are respectively disposed on the upper and lower sides of the wafer along the wafer axis. The second and third marker cameras are disposed between the first and fourth marker cameras. The second marker camera captures an image of the chamfered area on the upper side of the wafer edge, and the third marker camera captures an image of the chamfered area on the upper side of the wafer edge. The light source of the marker detection unit includes a coaxial light source, which is disposed between the marker camera lens and the wafer.

[0008] Preferably, the axes of the plurality of circular cameras are arranged in a coplanar manner, and the plane containing the axes of the circular cameras is parallel to the wafer axis; the axes of the plurality of marker cameras are arranged in a coplanar manner, and the plane containing the axes of the marker cameras is parallel to the wafer axis.

[0009] Preferably, the surface defect detection assembly includes a second fixed frame, and a detection light source, a wafer support mechanism, and a surface detection device mounted on the second fixed frame. The wafer support mechanism is used to place the wafer to be inspected, and the illumination direction of the detection light source is towards the wafer to be inspected. The surface detection device includes a primary inspection camera, a secondary inspection camera, and a depth detection sensor that act sequentially and are arranged along the X direction. The wafer support mechanism includes a second slide rail and a second sliding frame. The second slide rail extends along the X direction, and the second sliding frame is slidably mounted on the second slide rail and carries the wafer sequentially into the shooting range of the primary inspection camera, the secondary inspection camera, and the depth detection sensor.

[0010] Based on the above scheme, the detection light source includes a first detection light source and a second detection light source. The first detection light source is disposed above the wafer and the illumination direction is towards the upper surface of the wafer. The second detection light source is disposed below the wafer and the illumination direction is towards the lower surface of the wafer. The surface detection device includes a first surface detection device and a second surface detection device. The first surface detection device is disposed above the wafer, and the second surface detection device is disposed below the wafer. The camera shooting direction of both the first surface detection device and the second surface detection device is along the Z direction and towards the wafer.

[0011] Preferably, the surface detection device further includes a third slide rail and a third sliding frame. The third slide rail extends along the Y direction, and the third sliding frame is movably mounted on the third slide rail and slides along the Y direction. The initial inspection camera, the re-inspection camera, and the depth detection sensor are mounted on the third sliding frame.

[0012] Preferably, the wafer support mechanism further includes a support unit, which is fixedly mounted on the second sliding frame. There are multiple support units, which are symmetrically arranged about the center of the wafer. The support unit is provided with support fingers, and the end of the support fingers near the center of the wafer is provided with a stepped support portion, on which the wafer rests.

[0013] Based on the above scheme, the support unit also includes a sliding drive, a sliding action, and a sliding guide rail. The sliding guide rail is fixedly installed on the second sliding frame along the wafer radial direction. The sliding action is slidably disposed on the sliding guide rail and moves along the wafer radial direction. The sliding drive drives the sliding action to move. The support finger is fixedly installed on the sliding action.

[0014] Preferably, the housing has a first placement position and a second placement position next to the edge defect detection assembly and the surface defect detection assembly, respectively. The wafer moving mechanism also includes a moving slide rail, the robotic arm is movably mounted on the moving slide rail, the edge finding mechanism is located at the end of the moving slide rail, the compartment door is located on one side of the moving slide rail, and the first placement position and the second placement position are located on the other side of the moving slide rail.

[0015] The beneficial effects of this utility model are as follows: 1. Integrating the wafer edge defect detection assembly and the surface defect detection assembly into one set of equipment allows for the completion of both surface defect detection and edge defect detection functions in a single device. This avoids contamination of wafers during transport between different devices, while also improving wafer inspection efficiency and saving equipment space. 2. The wafer edge defect detection assembly, by setting up a circumferential detection unit and a marker detection unit on the side of the wafer, can complete the detection of edge defects and notch morphology around the entire circumference within one rotation cycle of the wafer, effectively improving the edge detection efficiency of the wafer; it uses a camera to acquire images of the wafer edge area and performs defect detection and identification, avoiding secondary damage to the wafer during the detection process through non-contact measurement; both the circumferential detection unit and the marker detection unit are equipped with multiple cameras on the side of the wafer, so that complete image acquisition can be performed at different positions on the curved surface of the wafer edge, avoiding problems such as image distortion or incomplete acquisition; 3. The surface defect detection assembly integrates a primary inspection camera, a secondary inspection camera, and a depth detection sensor, enabling wafers to complete three rounds of inspection—rapid coarse inspection, fine secondary inspection, and defect depth detection—on a single device, efficiently meeting the accuracy and reliability requirements for surface defect detection. By placing the surface inspection device on the top and bottom sides of the wafer, comprehensive inspection of surface defects on both sides of the wafer can be completed in a single inspection, resulting in high inspection efficiency. Furthermore, the inspection results from both sides do not interfere with each other, ensuring the accuracy and reliability of the inspection results. Attached Figure Description

[0016] Figure 1 : A schematic diagram of the structure of this utility model; Figure 2 : Schematic diagram of the internal structure of the box body of this utility model; Figure 3 : A schematic diagram of the structure of this utility model after removing the box body; Figure 4 : A schematic diagram of the structure of this utility model from another perspective after removing the box body; Figure 5 : Schematic diagram of the edge defect detection assembly of this utility model; Figure 6 : Another perspective structural schematic diagram of the edge defect detection assembly of this utility model; Figure 7 Front view of the circumferential detection unit of this utility model; Figure 8 Front view of the flag detection unit of this utility model; Figure 9 : Schematic diagram of the surface defect detection assembly of this utility model; Figure 10 : Another structural schematic diagram of the surface defect detection assembly of this utility model; Figure 11 : Schematic diagram of the installation position of the surface detection device of this utility model; Figure 12 : Schematic diagram of the wafer support mechanism of this utility model; Figure 13 This utility model Figure 12 Enlarged view of part A in the middle. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments: In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between 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.

[0018] In the description of this utility model, it should be understood that the terms "center," "length," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," and "inner," 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 be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0019] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0020] like Figures 1 to 12 As shown, a wafer inspection device includes a housing 11. The housing 11 has a wafer cassette placement position 12 and a door 13. The wafer cassette placement position 12 is used to hold wafer cassettes containing wafers to be inspected. The door 13 is openable and closable. When the door 13 is open, the space inside the wafer cassette in the wafer cassette placement position 12 is connected to the internal space of the housing 11. The housing 11 also has an operation equipment placement position 14 for placing central control equipment and display equipment for operating the inspection equipment or observing the inspection results.

[0021] The housing 11 is equipped with a wafer moving mechanism, an edge finding mechanism 3, an edge defect detection assembly, and a surface defect detection assembly. The edge finding mechanism 3 is an edge finder, which can be selected from existing technology equipment, to detect the notch angle position of the wafer 6, and even the eccentricity and eccentricity angle when the wafer 6 is placed.

[0022] The wafer moving mechanism includes a robotic arm 22 for gripping and picking up wafers 6. The robotic arm 22 reciprocates between the door 13, the edge finding mechanism 3, the edge defect detection assembly, and the surface defect detection assembly to transfer wafers 6. Specifically, the housing 11 is provided with a first placement position 15 and a second placement position 16 next to the edge defect detection assembly and the surface defect detection assembly, respectively. The wafer moving mechanism also includes a moving slide rail 21. The robotic arm 22 is movably mounted on the moving slide rail 21. The edge finding mechanism 3 is located at the end of the moving slide rail 21. The door 13 is located on one side of the moving slide rail 21. The first placement position 15 and the second placement position 16 are located on the other side of the moving slide rail 21, thereby facilitating the robotic arm 22 to pick up and transfer wafers 6 during the detection process.

[0023] The edge defect detection assembly includes a wafer carrier 43 for supporting the wafer 6 and an edge detection device for detecting defects and morphology of the edges and notches of the wafer 6; the surface detection assembly includes a wafer support mechanism and a surface detection device for detecting defects on the wafer surface, wherein the wafer support mechanism carries the wafer 6 to the shooting range of each camera in the surface detection device.

[0024] like Figures 4 to 8 As shown, the wafer carrier device 43 can adopt a solution in the prior art, such as the technical solutions disclosed in Chinese invention patents CN119852237A and CN117558672A. The wafer carrier device 43 includes a carrier unit and a turntable. The turntable is arranged in a horizontal direction. There are multiple carrier units, which are circumferentially distributed on the turntable. The carrier unit includes a horizontal moving mechanism and a vertical moving mechanism. The horizontal moving mechanism includes a horizontal driving member and a horizontal sliding block. The horizontal sliding block moves radially back and forth along the turntable under the action of the horizontal driving member. The vertical moving mechanism is arranged on the horizontal sliding block and includes a vertical driving member and a vertical sliding block. The vertical sliding block moves up and down in the vertical direction on the horizontal sliding block under the action of the vertical driving member. A gripper for holding the wafer is fixedly connected to the vertical sliding block. The wafer carrier is slidably mounted on a first slide rail 42, which is arranged along the X direction and is mounted on a first fixing frame 41, which is fixedly arranged relative to the housing 11. The wafer carrier 43 carries the wafer 6 on the first slide rail 42 and moves between the first placement position 15 and the edge defect detection position.

[0025] The edge detection device includes a circumferential detection unit 45 and a marker detection unit 46, which are disposed at the edge defect detection position. The circumferential detection unit is disposed on one side of the wafer 6 and includes a circumferential camera and a light source for capturing images of the outer edge of the wafer 6. The number of circumferential cameras is multiple. The marker detection unit includes a marker camera and a light source for capturing images of the notch shape of the wafer 6. The edge detection device also includes a host computer and a processor for processing and identifying the images captured by each camera to obtain the wafer edge defect identification result.

[0026] The cameras are mounted on the first fixed frame 41 via camera mounting bracket 441, and each camera is connected to a camera adjustment mechanism 442 to adjust the spatial position and angle parameters of each camera.

[0027] The circumferential detection unit includes a first circumferential camera 451, a second circumferential camera 452, and a third circumferential camera 453. The first and third circumferential cameras 451 and 453 are respectively positioned on the upper and lower sides of the wafer 6 along its axial direction, and capture images of the wafer 6 from its outer edge to a predetermined radial distance inward. For example, if the predetermined distance is 3mm, the first and third circumferential cameras 451 and 453 capture images of the area 3mm inward from the edge on the upper and lower surfaces of the wafer 6. The second circumferential camera 452 is positioned radially along the wafer 6 and on the center plane in the thickness direction of the wafer 6, capturing images of the outer edge of the wafer 6. By stitching together the images captured by the three circumferential cameras, a complete image of the edge region of the wafer 6 can be obtained.

[0028] During thin film deposition and photoresist coating processes, wafers undergo chamfering, which increases the shape complexity of the curved areas at the wafer edges. To address this, the circumferential detection unit further includes a fourth circumferential camera and a fifth circumferential camera (not shown in the figure). The fourth circumferential camera is positioned between the first circumferential camera 451 and the second circumferential camera 452, and captures an image of the upper chamfered area at the edge of wafer 6. The fifth circumferential camera is positioned between the second circumferential camera 452 and the third circumferential camera 453, and captures an image of the lower chamfered area at the edge of wafer 6. This allows for the capture of chamfered areas. The captured chamfered images are then stitched together with images of the upper surface, lower surface, and ends of the wafer to obtain a complete image of the edge region of wafer 6.

[0029] The light source of the circumferential detection unit is a ring light source 454. The opening of the ring light source 454 faces one side of the wafer 6, and the area of ​​the wafer 6 to be photographed extends into the opening of the ring light source 454. The effective illumination angle of the ring light source 454 is greater than 180°, so that the illumination range of the ring light source 454 covers the shooting range of each camera in the circumferential detection unit. The ring light source 454 provides uniform, shadowless illumination to the curved surface area of ​​the wafer edge, reducing shadow blind spots and improving the image quality captured by the camera. Preferably, the light source of the circumferential detection unit also includes enhancement light sources 455, which can be fiber optic light sources. There are two enhancement light sources 455, which are arranged on the upper and lower sides of the wafer 6. The enhancement light sources 455 supplement the light to the edge area of ​​the wafer, thereby improving the illumination effect.

[0030] The marker detection unit includes a first marker camera 461 and a fourth marker camera 464. The first marker camera 461 and the fourth marker camera 464 are respectively positioned on the upper and lower sides of the wafer 6 along the axial direction of the wafer 6, and capture images of the notch position morphology of the wafer 6. When the wafer 6 rotates until the notch is within the acquisition range of the first marker camera 461 and the fourth marker camera 464, the wafer 6 stops rotating, and the notch morphology is captured by the marker cameras to detect the notch position. For wafers that have undergone chamfering, the marker detection unit further includes a second marker camera 462 and / or a third marker camera 463. The second marker camera 462 and the third marker camera 463 are positioned between the first marker camera 461 and the fourth marker camera 464. The second marker camera 462 captures an image of the chamfered area on the upper side of the edge of wafer 6, and the third marker camera 463 captures an image of the chamfered area on the lower side of the edge of wafer 6, thereby capturing the chamfered area at the notch position. The captured chamfered area image is then stitched together with the images of the upper and lower surfaces to obtain a complete image of the notch area of ​​wafer 6.

[0031] The light source of the marker detection unit includes a marker detection light source, which is positioned between the marker camera lens and the wafer 6. The marker detection unit is a coaxial surface light source, and the marker detection camera is a dark-field camera. When the light emitted by the marker detection light source illuminates the defect area, it will be scattered. The scattered light enters the camera to collect and identify the defect morphology. Specifically, the marker detection light source includes a first detection light source 465 and a second detection light source 466. The first detection light source 465 is a hollow coaxial light source and is respectively positioned at the lens ends of the second marker detection camera 462 and the third marker detection camera 463, with the illumination direction consistent with the axis of the connected camera. The second detection light source 466 is positioned on the upper and lower sides of the wafer 5, with the illumination direction forming an acute angle with the plane where the wafer 5 is located, thereby providing a light source for each marker detection camera to capture the morphology of the wafer notch position.

[0032] The axes of the multiple circumferential cameras are arranged in a coplanar manner, and the plane containing the axes of the circumferential cameras is parallel to the axis of wafer 6; the axes of the multiple marker cameras are also arranged in a coplanar manner, and the plane containing the axes of the marker cameras is parallel to the axis of wafer 6. This allows each camera in the circumferential detection unit and each camera in the marker detection unit to be set in the same longitudinal plane, facilitating synchronous shooting of the same position on the edge of the wafer, and stitching the captured results together to improve the detection effect.

[0033] During the inspection process, when detecting defects at the wafer edge, the turntable 412 drives the wafer 6 to rotate. During the rotation, each camera in the circumferential inspection unit continuously captures multi-point images of the wafer 6 edge. After the wafer 6 rotates one full circle or more, the acquisition of a complete edge image of the wafer 6 is completed. When detecting defects at the notch of the wafer 6, the notch position of the wafer 6 is rotated to the shooting range of each marker camera in the marker detection unit. After that, the wafer 6 is kept fixed, and the marker cameras capture and acquire images of the wafer notch, thereby performing defect detection.

[0034] like Figures 9 to 11 As shown, the surface defect detection assembly includes a second mounting frame 51, and a detection light source 52, a wafer support mechanism, and a surface detection device mounted on the second mounting frame 51. The second mounting frame 51 is fixedly disposed relative to the housing 11. The wafer support mechanism is used to place the wafer 6 to be inspected, and the illumination direction of the detection light source 52 is towards the wafer 6 to be inspected, so as to provide the necessary illumination for the cameras and sensors of the surface detection device to capture images.

[0035] The surface inspection device includes a primary inspection camera 561, a secondary inspection camera 562, and a depth detection sensor 563 arranged sequentially along the X-direction. However, the order of the primary inspection camera 561, secondary inspection camera 562, and depth detection sensor 563 can include various arrangements. The primary inspection camera 561 can be a line scan camera, used to quickly and extensively scan the surface of the wafer 6 to perform preliminary identification and location of defects and suspected defects, and to mark the locations where defects may exist in the initial inspection results. The secondary inspection camera 562 performs a high-precision second inspection on the marked areas to confirm whether it is a defect, the type of defect, and the specific morphology of the defect. The depth detection sensor 563 can be a spectral confocal sensor, which uses a light spot to illuminate the defect to be detected on the wafer surface and analyzes the offset of the reflected wavelength at each location to complete the depth detection.

[0036] To facilitate the completion of the above-mentioned testing scheme, the wafer support mechanism includes a second slide rail 531 and a second sliding frame 532. The second slide rail 531 extends along the X direction, and the second sliding frame 532 is slidably mounted on the second slide rail 531, and carries the wafer 6 into the shooting range of the initial inspection camera 561, the re-inspection camera 562 and the depth detection sensor 563 in sequence.

[0037] The detection light source 52 includes a first detection light source and a second detection light source. The first detection light source is positioned above the wafer 6 and the illumination direction is towards the upper surface of the wafer 6. The second detection light source is positioned below the wafer 6 and the illumination direction is towards the lower surface of the wafer 6. The surface detection device includes a first surface detection device and a second surface detection device. The first surface detection device is positioned above the wafer 6, and the second surface detection device is positioned below the wafer 6. The camera shooting direction of both the first surface detection device and the second surface detection device is along the Z direction and towards the wafer 6, so that the upper and lower surfaces of the wafer 6 can be detected simultaneously.

[0038] Preferably, due to the large size of wafer 6, in order to ensure the detection accuracy of the camera, the shooting range of the camera that can be used is usually small, and it is not possible to quickly complete the detection of the wafer surface with a single camera. Therefore, multiple identical cameras are used for detection. Specifically, there are multiple primary inspection cameras 561, and the multiple primary inspection cameras 561 are arranged along the Y direction; there are multiple secondary inspection cameras 562, and the multiple secondary inspection cameras 562 are arranged along the Y direction; there are multiple depth detection sensors 563, and the multiple depth detection sensors 563 are arranged along the Y direction to improve detection efficiency.

[0039] Furthermore, the surface inspection device also includes a third slide rail 551 and a third sliding frame 552. The third slide rail 551 extends along the Y direction, and the third sliding frame 552 is movably mounted on the third slide rail 551 and slides along the Y direction. The initial inspection camera 561, the re-inspection camera 562, and the depth detection sensor 563 are mounted on the third sliding frame 552. Taking the initial inspection camera 561 as an example, after the wafer support mechanism carries the wafer 6 and moves it a certain distance along the X direction, and the initial inspection camera 561 completes the inspection in that direction, the third sliding frame 552 moves a certain distance on the third slide rail 551, and the moving distance is not greater than the length of the shooting range of the initial inspection camera 561 in the X direction. Then, the wafer support mechanism carries the wafer 6 and moves it again along the X direction, so that the initial inspection camera 561 can inspect the uninspected areas; the above process is repeated until the inspection is completed. Taking the re-inspection camera 562 and the depth detection sensor 563 as an example, after the initial inspection marking is completed, the marking area falls into the detection range of the re-inspection camera 562 or the depth detection sensor 563 by moving the second sliding frame 532 and the third sliding frame 552, and then the re-inspection or depth detection is carried out.

[0040] like Figure 12 and Figure 13As shown, the wafer support mechanism further includes a support unit 54, which is fixedly mounted on the second sliding frame 532. The number of support units 54 is multiple and symmetrically arranged about the center of the wafer 6; preferably, the number of support units 54 can be four. Support fingers 544 are provided on the support unit 54. The ends of the support fingers 544 near the center of the wafer 6 are provided with stepped support portions. The wafer 6 rests on the support portions. Specifically, the support portion includes a support surface arranged along the XOY plane and a snap-fit ​​surface arranged perpendicular to the support surface. The lower surface of the wafer 6 rests on the support surface to achieve load bearing, while the snap-fit ​​surface abuts against the outer edge of the wafer 6 to achieve fixation.

[0041] The supporting unit 54 also includes a sliding drive 541, a sliding actuator 542, and a sliding guide rail 543. The sliding drive 541 can be a cylinder, motor, or other drive component capable of linear motion. The sliding guide rail 543 is fixedly mounted on the second sliding frame 532 along the radial direction of the wafer 6. The sliding actuator 542 is slidably disposed on the sliding guide rail 543 and moves radially along the wafer 6. The sliding drive 541 drives the sliding actuator 542 to move. The supporting finger 544 is fixedly mounted on the sliding actuator 542. When the wafer 6 to be inspected is transferred to the wafer supporting mechanism by a robotic arm or other transfer mechanism, the sliding drive 541 drives the sliding actuator 542 to move inward along the radial direction of the wafer until the supporting surface and the snap-fit ​​surface abut against the lower surface and outer edge of the wafer, respectively, completing the supporting action, and the robotic arm retracts. After the inspection is completed, wafer 6 is transported back to its original position by the wafer support mechanism. The robotic arm extends and receives wafer 6, and the sliding drive 541 drives the sliding actuator 542 to move radially outward along the wafer until it detaches from wafer 6. A sliding detection element 545 is fixedly connected to the sliding actuator 542, and a limit switch 546 is fixedly installed on the second sliding frame 532. The limit switch 546 detects the position of the sliding detection element 545 and feeds back the position signal to the sliding drive 541, thereby determining whether the movement of the sliding actuator 542 is in place and whether the movement of the sliding drive 541 is started or stopped through the feedback signal.

[0042] The method of using wafer inspection equipment includes the following steps: S1. Place the wafer cassette containing the wafer to be tested at wafer cassette placement position 12; S2. The cassette door 13 is opened, and the wafer moving mechanism moves to the cassette door 13 to take the wafer 6 to be tested from the wafer cassette. S3. The robotic arm 22 of the wafer moving mechanism sends the wafer 6 to the edge finding mechanism 3 to detect the notch angle position of the wafer 6, perform wafer 6 angle positioning and eccentricity correction, so that the center of the wafer 6 is aligned with the center of the gripping finger of the robotic arm 22. S4. After edge detection is completed, the notch position information of wafer 6 is recorded. The wafer moving mechanism sends wafer 6 to the edge defect detection assembly through the first placement position 15. The circumferential detection unit and the marker detection unit of the edge defect detection assembly detect wafer 6. S4-1. The robotic arm 22 places the wafer 6 on the wafer carrier 43, which is stationed at the first placement position 15. The wafer carrier 43 moves on the first slide rail 42 to the edge defect detection position to perform edge defect detection. S4-2. The turntable drives wafer 6 to rotate. During the rotation of wafer 6, each camera in the circumferential detection unit continuously captures multi-point images of the edge of wafer 6. After wafer 6 rotates one full circle or more, the acquisition of the complete edge image of wafer 6 is completed. S4-3. When detecting defects at the notch of wafer 6, the notch position of wafer 6 is rotated to the shooting range of each marker camera in the marker detection unit. Then, wafer 6 is kept fixed, and the marker cameras capture and acquire images of the notch, thereby performing defect detection at the notch position. S4-4. After the edge defect detection is completed, the wafer carrier 43 moves on the first slide rail 42 to the first placement position 15 and is taken away by the robotic arm 22. S5. The robotic arm 22 delivers wafer 6 through the second placement position 16 to the surface defect detection assembly for surface defect detection: S5-1. The wafer support mechanism moves to the second placement position 16, and the robotic arm 22 places the wafer 6 on the wafer support mechanism; S5-2. The wafer support mechanism moves the wafer 6 into the shooting range of the primary inspection camera 561, which then takes pictures and inspects the surface, marking the defect locations and / or potential defect locations in the inspection results. S5-3. The re-inspection camera 562 performs a high-precision second inspection on the marked area to confirm whether it is a defect, the type of defect, and the specific morphology of the defect. S5-4. The depth detection sensor 563 can be a spectral confocal sensor. It uses a light spot to illuminate the defect to be detected on the wafer surface and analyzes the offset of the reflected wavelength at each position to complete the depth detection of the surface defect. S5-5. The wafer support mechanism transfers the inspected wafer 6 to the second placement position 16; S6. The robotic arm 22 takes out the inspected wafer 6 from the second placement position 16 and puts it into the original wafer cassette or a new wafer cassette, or transfers the wafer 6 to the next process.

[0043] The present invention has been described above by way of example, but the present invention is not limited to the specific embodiments described above. Any modifications or variations made based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A wafer inspection device, characterized in that, The device includes a housing (11), a wafer cassette placement position (12) and a storage door (13) on the housing (11). Inside the housing (11) are a wafer moving mechanism, an edge finding mechanism (3), an edge defect detection assembly and a surface defect detection assembly. The wafer moving mechanism includes a robotic arm (22) for clamping and picking up wafers (6). The robotic arm (22) moves back and forth between the storage door (13), the edge finding mechanism (3), the edge defect detection assembly and the surface defect detection assembly to transfer wafers (6). The edge defect detection assembly includes a wafer support device (43) for carrying wafers (6) and an edge detection device for detecting defects and morphology of the edges and notches of wafers (6). The surface defect detection assembly includes a wafer support mechanism and a surface detection device for detecting defects on the wafer surface. The wafer support mechanism carries wafers (6) to the shooting range of each camera in the surface detection device.

2. The wafer inspection equipment according to claim 1, characterized in that, The edge detection device includes a circumferential detection unit (45) and a marker detection unit (46). The circumferential detection unit is located on one side of the wafer (6) and includes a circumferential camera and a light source for capturing images of the outer edge of the wafer (6). The number of circumferential cameras is multiple. The marker detection unit includes a marker camera and a light source for capturing images of the notch morphology of the wafer (6). The number of marker cameras is multiple.

3. The wafer inspection equipment according to claim 2, characterized in that, The circumferential detection unit includes a first circumferential camera (451), a second circumferential camera (452), and a third circumferential camera (453). The first circumferential camera (451) and the third circumferential camera (453) are respectively arranged on the upper and lower sides of the wafer (6) along the axial direction of the wafer (6) and capture images of the wafer (6) from the outer edge to a predetermined distance in the radial direction. The second circumferential camera (452) is arranged along the radial direction of the wafer (6) and is located on the central plane in the thickness direction of the wafer (6) to capture images of the outer edge of the wafer (6). The light source of the circumferential detection unit is a ring light source (454). The opening of the ring light source (454) faces the wafer (6) and the area of ​​the wafer (6) to be photographed is deep into the opening of the ring light source (454). The illumination range of the ring light source (454) covers the shooting range of each camera in the circumferential detection unit.

4. A wafer inspection device according to claim 2, characterized in that, The marker detection unit includes a first marker camera (461), a second marker camera (462), a third marker camera (463), and a fourth marker camera (464). The first marker camera (461) and the fourth marker camera (464) are respectively arranged on the upper and lower sides of the wafer (6) along the wafer (6) axis. The second marker camera (462) and the third marker camera (463) are arranged between the first marker camera (461) and the fourth marker camera (464). The second marker camera (462) captures an image of the chamfered area on the upper edge of the wafer (6), and the third marker camera (463) captures an image of the chamfered area on the upper edge of the wafer (6). The light source of the marker detection unit includes a coaxial light source (465), which is arranged between the marker camera lens and the wafer (6).

5. A wafer inspection device according to claim 2, characterized in that, The axes of the plurality of circular cameras are arranged in a coplanar manner, and the plane containing the axes of the circular cameras is parallel to the axis of the wafer (6); the axes of the plurality of marker cameras are arranged in a coplanar manner, and the plane containing the axes of the marker cameras is parallel to the axis of the wafer (6).

6. The wafer inspection equipment according to claim 1, characterized in that, The surface defect detection assembly includes a second fixed frame (51), a detection light source (52), a wafer support mechanism, and a surface detection device mounted on the second fixed frame (51). The wafer support mechanism is used to place the wafer (6) to be inspected. The illumination direction of the detection light source (52) is towards the wafer (6) to be inspected. The surface detection device includes a primary inspection camera (561), a secondary inspection camera (562), and a depth detection sensor (563) arranged sequentially along the X direction. The wafer support mechanism includes a second slide rail (531) and a second sliding frame (532). The second slide rail (531) extends along the X direction. The second sliding frame (532) is slidably mounted on the second slide rail (531) and carries the wafer (6) into the shooting range of the primary inspection camera (561), the secondary inspection camera (562), and the depth detection sensor (563) in sequence.

7. A wafer inspection device according to claim 6, characterized in that, The detection light source (52) includes a first detection light source and a second detection light source. The first detection light source is disposed above the wafer (6) and the illumination direction is towards the upper surface of the wafer (6). The second detection light source is disposed below the wafer (6) and the illumination direction is towards the lower surface of the wafer (6). The surface detection device includes a first surface detection device and a second surface detection device. The first surface detection device is disposed above the wafer (6), and the second surface detection device is disposed below the wafer (6). The camera shooting direction of the first surface detection device and the second surface detection device is along the Z direction and towards the wafer (6).

8. A wafer inspection device according to claim 6, characterized in that, The surface inspection device also includes a third slide rail (551) and a third sliding frame (552). The third slide rail (551) extends along the Y direction, and the third sliding frame (552) is movably mounted on the third slide rail (551) and slides along the Y direction. The initial inspection camera (561), the re-inspection camera (562) and the depth detection sensor (563) are mounted on the third sliding frame (552).

9. A wafer inspection device according to claim 6, characterized in that, The wafer support mechanism also includes a support unit (54), which is fixedly mounted on the second sliding frame (532). There are multiple support units (54), which are symmetrically arranged about the center of the wafer (6). Support fingers (544) are provided on the support unit (54). The end of the support finger (544) near the center of the wafer (6) is provided with a stepped support portion, and the wafer (6) is attached to the support portion.

10. A wafer inspection device according to claim 9, characterized in that, The supporting unit (54) further includes a sliding drive (541), a sliding actuator (542), and a sliding guide rail (543). The sliding guide rail (543) is fixedly mounted on the second sliding frame (532) along the wafer (6). The sliding actuator (542) is slidably disposed on the sliding guide rail (543) and moves along the wafer (6) radially. The sliding drive (541) drives the sliding actuator (542) to move. The supporting finger (544) is fixedly mounted on the sliding actuator (542).

11. A wafer inspection device according to claim 1, characterized in that, The housing (11) has a first placement position (15) and a second placement position (16) respectively next to the edge defect detection assembly and the surface defect detection assembly. The wafer moving mechanism also includes a moving slide rail (21). The robotic arm (22) is movably mounted on the moving slide rail (21). The edge finding mechanism (3) is mounted at the end of the moving slide rail (21). The door (13) is mounted on one side of the moving slide rail (21). The first placement position (15) and the second placement position (16) are mounted on the other side of the moving slide rail (21).

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