Wafer grinding equipment and wafer edge searching and positioning method

Abstract

The invention relates to the technical field of chip manufacturing, and provides wafer grinding equipment and a wafer edge searching positioning method.A wafer to be machined is placed on a positioning suction cup to be rotated by arranging a wafer eccentric positioning assembly, and it is determined that the connecting line of the circle center of the wafer and the circle center of a wafer discharging suction cup is parallel to the X-axis direction through an image recognition device; and then the control unit is used for controlling the carrying assembly to transfer the wafer to the wafer discharging suction cup in the X-axis direction, so that compensation in the X-axis direction is achieved, eccentric calibration of the wafer is further achieved, and compared with existing mechanical positioning, vacuum adsorption or non-adsorption is conducted after positioning is completed, the large variable quantity exists, and the positioning accuracy is improved. Meanwhile, due to the fact that the sizes of light spots of the detection devices such as the correlation sensor are larger than those of cameras in precision, mechanical positioning further has machining errors, higher positioning precision is achieved compared with the prior art, and the precision of the follow-up machining technology can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of chip cutting, and in particular to a wafer grinding device and a wafer edge finding and positioning method. Background Art

[0002] In the semiconductor device manufacturing process, the metal layer is masked or the back of the wafer is thinned by a wafer grinding device. In order to ensure the grinding accuracy, the wafer needs to be positioned and calibrated first. The existing grinding equipment mainly relies on mechanical devices for positioning when performing positioning and calibration, that is, it is composed of a motor, a gear transmission, a positioning connector and other structures. A plurality of positioning members are arranged around the adsorption block ring on the turntable bottom plate, and the positioning members are slidably connected to the bottom plate, and the turntable is arranged below the bottom plate; a plurality of connecting components are rotatably connected to the turntable, and each of the connecting components is rotatably connected to a positioning member on the side away from the turntable to drive the positioning member to slide toward the side close to or away from the adsorption block, thereby achieving positioning. In addition, the wafer compensation device can also use optical sensing to confirm the boundary position of the wafer. This method relies on installing sensors such as beams and lasers, adsorbing the wafer on the adsorption block, rotating the wafer, rotating the wafer to one end point of the notch or flat edge, remembering the position at this time, and then rotating to the other end point of the flat edge, and determining the notch and flat edge feature position by calculating the middle point of the two position coordinates. At the same time, the optical sensing method often requires mechanical positioning to assist in locating the center of the circle.

[0003] Both of the above positioning and calibration methods have certain problems: mechanical positioning can only locate the center of the circle, but with the change of technology, customers gradually begin to require the recognition of features such as notches and flat edges, and mechanical positioning often has difficulty in accurately locating notches, flat edges and other features, and it is difficult to feedback the current location of the feature. The use of optical sensing to confirm the boundary position of the wafer requires the installation of optical sensors on the upper and lower sides around the wafer, which will cause great interference to the wafer handling process, and the light beam is often too large, so there is often a certain deviation when detecting the position, so the accuracy is not particularly high. At the same time, the optical sensing method often requires mechanical positioning to assist in locating the center of the circle, and the positioning and calibration process is relatively cumbersome. Summary of the invention

[0004] The object of the present invention is to provide a wafer grinding device and a wafer edge finding and positioning method to solve the problem that the positioning and calibration accuracy of the existing wafer grinding device is low and the calibration is complicated.

[0005] In a first aspect, an embodiment of the present invention provides a wafer grinding device, including: a loading component, a cleaning component, and a wafer eccentric positioning component, wherein the wafer eccentric positioning component includes: Wafer discharge suction cup, used to place the wafer to be processed after eccentric positioning; A positioning suction cup, the positioning suction cup is used to place the wafer to be processed transferred from the loading platform, and the positioning suction cup is driven to rotate by a rotary drive mechanism; An image recognition device, which is arranged on a workbench and is used to obtain image information of the wafer to be processed, so as to determine the offset between the center of the wafer to be processed and the wafer calibration discharge suction cup along the Y-axis direction; A control unit is electrically connected to the positioning suction cup, the rotation drive mechanism and the image recognition device, and is used to control the rotation drive mechanism to operate according to the offset of the center of the wafer to be processed and the wafer calibration discharge suction cup along the Y-axis direction, so that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup is parallel to the X-axis direction.

[0006] Optionally, the wafer grinding equipment further comprises: a transport assembly, the transport assembly being arranged on the workbench; the transport assembly being connected to an X-axis drive mechanism on the workbench via a Z-axis drive mechanism; The control unit is electrically connected to the X-axis drive mechanism, the Z-axis drive mechanism and the transport component, and is used to control the transport component to transfer the wafer to be processed from the positioning suction cup along the X-axis direction to the wafer discharge suction cup after determining that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup is parallel to the X-axis direction, so as to carry out subsequent grinding process.

[0007] Optionally, the work frame includes: a frame body and a sliding guide rail installed on the frame body; the frame body and the sliding guide rail both extend along the X-axis direction, the Z-axis drive mechanism and the conveying assembly are both slidably connected to the sliding guide rail through a Z-axis arm, and the Z-axis arm is driven to move along the X-axis direction through the X-axis drive mechanism.

[0008] Optionally, the rotary drive mechanism is disposed below the positioning suction cup, the rotary drive mechanism is connected to a rotary joint via a belt, and the upper end of the rotary joint is connected to the positioning suction cup via a rotating shaft, thereby driving the rotation of the positioning suction cup through the rotary drive mechanism.

[0009] Optionally, the wafer grinding equipment also includes: a rough grinding station and a fine grinding station, the rough grinding station and the wafer discharge suction cup are located on the same side of the work frame, and the fine grinding station is located on the other side of the work frame; after eccentric positioning and edge finding, the wafer to be processed passes through the rough grinding station and the fine grinding station in sequence for rough grinding and fine grinding processes respectively.

[0010] Optionally, the wafer grinding equipment further includes: a polishing station; the polishing station and the fine grinding station are located on the same side of the workbench, and are used for performing polishing after fine grinding of the wafer.

[0011] Optionally, the wafer grinding equipment also includes: a conveying component and a wafer back side cleaning station, the conveying component is arranged on one side of the wafer discharge suction cup and the wafer back side cleaning station, and is used to convey the polished wafer to the wafer back side cleaning station for back side cleaning.

[0012] Optionally, the wafer grinding equipment further includes: a backlight source; the backlight source is arranged on a side of the positioning suction cup away from the wafer discharge suction cup, and is used to provide supplementary light when the image recognition device obtains image information of the wafer to be processed.

[0013] In a second aspect, an embodiment of the present invention further provides a wafer edge finding and positioning method, based on a wafer grinding device, the wafer grinding device includes a control unit and a wafer discharge suction cup, a positioning suction cup, an image recognition device and a transport component electrically connected to the control unit respectively, the image recognition device is arranged on a workbench, and is used to obtain image information of the wafer to be processed, and the transport component is used to transfer the wafer to be processed from the positioning suction cup along the X-axis direction to the wafer discharge suction cup, and the wafer edge finding and positioning method includes: S100, placing the wafer to be processed on the positioning suction cup and fixing it by adsorption; S200, obtaining the position change of the wafer radius relative to the calibration point through an image recognition device, fitting the coordinate position of the center, flat edge or notch of the current wafer, so as to determine the offset between the center of the wafer to be processed and the center of the wafer calibration discharge suction cup; wherein the calibration point is the center position of the calibration wafer when it is placed at the center of the positioning suction cup; S300, according to the offset between the center of the wafer to be processed and the center of the wafer calibration discharge suction cup, control the positioning suction cup to rotate so that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup is parallel to the X-axis direction; S400, determining the offset between the center of the wafer to be processed and the center of the wafer discharge suction cup along the X-axis direction, and controlling the transport component to move the wafer to be processed from the positioning suction cup to the wafer discharge suction cup according to the offset.

[0014] Optionally, while step S200 is being performed, the following steps are also included: S201, controlling the transport assembly to move to above the wafer to be processed; S202, controlling the positioning suction cup to rotate and grabbing the edge-finding mark of the wafer to be processed through an image recognition device to determine the position angle of the edge-finding mark relative to the center of the wafer to be processed.

[0015] The embodiments of the present invention have at least the following technical effects: The wafer grinding equipment provided by the embodiment of the present invention places the wafer to be processed on the positioning suction cup for rotation by setting a wafer eccentric positioning component, and determines through an image recognition device that the line connecting the center of the wafer and the center of the wafer discharge suction cup is parallel to the X-axis direction, thereby realizing alignment in the Y-axis direction, and then controls the conveying component through the control unit to transfer the wafer along the X-axis direction to the wafer discharge suction cup, thereby realizing compensation in the X-axis direction, and further realizing the eccentricity calibration of the wafer. Compared with the existing mechanical positioning, vacuum adsorption or no adsorption is performed after positioning is completed, and there is a large variation. At the same time, the detection devices such as the beam sensor have a large gap in accuracy compared with the camera due to the size of their light spots, and the mechanical positioning also has machining errors. Therefore, the embodiment of the present invention has higher accuracy than the prior art, which is beneficial to improving the accuracy of subsequent processing technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic diagram of the overall structure of a wafer grinding device provided by an embodiment of the present invention; Figure 2 A schematic diagram of a working frame and auxiliary structures of a wafer grinding device provided by an embodiment of the present invention; Figure 3 A schematic diagram of the connection structure of a positioning suction cup of a wafer grinding device provided by an embodiment of the present invention; Figure 4 A schematic diagram of the relative position relationship between a positioning suction cup and a wafer discharge suction cup of a wafer grinding device provided by an embodiment of the present invention; Figure 5 A schematic diagram of a rotation driving structure of a positioning suction cup of a wafer grinding device provided by an embodiment of the present invention; Figure 6 A schematic diagram of the connection between a control unit and various components of a wafer grinding device provided by an embodiment of the present invention; Figure 7 A schematic flow chart of a wafer edge finding and positioning method provided in an embodiment of the present invention.

[0018] Icons: 1-first loading platform; 2-second loading platform; 3-wafer back cleaning station; 4-wafer eccentric positioning assembly; 5-transmission assembly; 6-wafer discharge suction cup; 7-rough grinding station; 8-fine grinding station; 9-polishing station; 10-handling assembly; 11-manipulator assembly; 12-image recognition device; 13-X-axis drive mechanism; 14-Z-axis drive mechanism; 15-handling suction cup; 16-positioning suction cup; 17-backlight source; 18-rotation drive mechanism; 19-rotating joint; 20-discharge suction cup drive mechanism; 21-control unit. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the field to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0021] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0022] Combination Figures 1 to 6 As shown, an embodiment of the present invention provides a wafer grinding device, including: a loading component, a cleaning component, a wafer eccentric positioning component 4, and the wafer eccentric positioning component 4 includes: a wafer discharge suction cup 6, a positioning suction cup 16, an image recognition device 12 and a control unit 21.

[0023] Specifically, the positioning suction cup 16 is used to place the material from any loading platform ( Figure 1The figure shows two loading platforms, namely the first loading platform 1 and the second loading platform 2) that transfer the wafers to be processed. The wafers to be processed are transferred to the positioning suction cup 16 by the robot assembly 15. The positioning suction cup 16 is driven by the rotation drive mechanism 18 to rotate to achieve position adjustment in the Y-axis direction, that is, the positioning suction cup 16 can realize its own rotation, and the wafer discharge suction cup 6 is used to place the wafers to be processed after eccentric positioning.

[0024] The image recognition device 12 is arranged on a workbench ( Figure 2 The workbench is located in the middle of the entire wafer grinding equipment, and is used to load the handling assembly 10 and the positioning and calibration components such as the image recognition device 12. Among them, the image recognition device 12 is used to obtain the image information of the wafer to be processed to determine the offset between the center of the wafer to be processed and the wafer calibration discharge suction cup along the Y-axis direction. Optionally, the image recognition device 12 can also move along the X-axis direction and the Z-axis direction, so as to better capture clear wafer image information and adapt to wafer image information of different sizes.

[0025] The control unit 21 is electrically connected to the positioning suction cup 16, the rotation drive mechanism 18 and the image recognition device 12, and is used to control the rotation drive mechanism 18 to operate according to the offset of the center of the wafer to be processed and the wafer calibration discharge suction cup along the Y-axis direction, so that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup 6 is parallel to the X-axis direction, so that the eccentricity correction adjustment of the wafer from the positioning suction cup 16 to the wafer discharge suction cup 6 can be achieved through subsequent compensation in the X-axis direction.

[0026] Specifically, after the wafer to be processed is placed on the positioning suction cup 16, the rotating drive mechanism 18 absorbs and drives the wafer to be processed to rotate six times, each time by 60 degrees. After each rotation, the image recognition device 12 will take a photo, remember the corresponding points on the edge contour of the current wafer to be processed in the shooting angle of the image recognition device 12, compare the changes in the positions of the points in the six photos, fit the centers of several radius circles at the current angle, thereby inferring the center of the wafer to be processed, and comparing the offset of the center of the circle to be processed with the calibrated center position.

[0027] When taking six photos, features with edge-finding marks (flat edges or notches) will appear in several of the images. Based on the currently calculated line between the center of the wafer to be processed and the position of the notch flat edge feature in the camera field of view, the position of the flat edge or notch is deduced, and the angle of the line relative to the X-axis is stored. The notch or flat edge feature on the rotating wafer discharge suction cup 6 is also the current angle. The angular offset of the notch or flat edge is compensated by the rotation of the wafer discharge platform itself (the rotation of the wafer discharge platform itself is driven by the discharge suction cup drive mechanism 20), that is, the offset of the center Y axis is compensated by the rotation of the positioning suction cup 16, and the offset of the center X axis is compensated by the X-axis transfer.

[0028] Optionally, the wafer grinding equipment further includes: a transport assembly 10, which is arranged on a workbench; the transport assembly 10 is connected to an X-axis drive mechanism 13 on the workbench through a Z-axis drive mechanism 14, so that the Z-axis drive mechanism 14 and the transport assembly 10 are driven by the X-axis drive mechanism 13 to move along the X-axis direction, and the Z-axis drive mechanism 14 can independently drive the transport assembly 10 to move along the Z-axis direction, thereby realizing the lifting and lowering of the transport assembly 10. Optionally, the transport assembly 10 includes a transport suction cup 15, which is used to absorb and grasp the wafer, and is lifted and lowered through the Z-axis drive mechanism 14, and the wafer is transferred from the positioning suction cup 16 to the wafer discharge suction cup 6 through the X-axis drive mechanism 13.

[0029] Furthermore, the control unit 21 is electrically connected to the X-axis drive mechanism 13, the Z-axis drive mechanism 14 and the conveying assembly 10, and is used to control the conveying assembly 10 to transfer the wafer to be processed from the positioning suction cup 16 along the X-axis direction to the wafer discharge suction cup 6 after determining that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup 6 is parallel to the X-axis direction, so as to carry out subsequent grinding process.

[0030] The wafer grinding equipment provided in the embodiment of the present invention is provided with a wafer eccentric positioning component 4, so that the wafer to be processed is placed on the positioning suction cup 16 for rotation, and the image recognition device 12 is used to determine that the line connecting the center of the wafer and the center of the wafer discharge suction cup 6 is parallel to the X-axis direction, so as to achieve alignment in the Y-axis direction, and then the control unit 21 controls the conveying component 10 to transfer the wafer to the wafer discharge suction cup 6 along the X-axis direction, so as to achieve compensation in the X-axis direction, and then achieve eccentric calibration of the wafer. Compared with the existing mechanical positioning, vacuum adsorption or no adsorption is performed after positioning is completed, and there is a large variation. At the same time, the detection devices such as the beam sensor have a large gap in accuracy compared with the camera due to the size of their light spots, and the mechanical positioning also has machining errors. Therefore, the embodiment of the present invention has higher accuracy than the prior art, which is beneficial to improving the accuracy of subsequent processing technology.

[0031] In some embodiments, Figure 2 As shown, the working frame includes: a frame body and a sliding guide rail installed on the frame body; the frame body is fixed on the base of the grinding equipment, the frame body and the sliding guide rail both extend along the X-axis direction, the Z-axis driving mechanism 14 and the conveying assembly 10 are both slidably connected to the sliding guide rail through the Z-axis arm, and the Z-axis arm is driven to move along the X-axis direction through the X-axis driving mechanism 13.

[0032] In some embodiments, Figure 3 As shown, the rotary drive mechanism 18 is arranged below the positioning suction cup 16, and the rotary drive mechanism 18 is connected to the rotary joint 19 through a belt, and the upper end of the rotary joint 19 is connected to the positioning suction cup 16 through a rotating shaft, so that the rotation of the positioning suction cup 16 is driven by the rotary drive mechanism 18.

[0033] In some embodiments, continue to refer to Figure 1 The wafer grinding equipment further includes: a rough grinding station 7 and a fine grinding station 8. The rough grinding station 7 and the wafer discharge suction cup 6 are located on the same side of the work frame, and the fine grinding station 8 is located on the other side of the work frame. After eccentric positioning and edge finding, the wafer to be processed passes through the rough grinding station 7 and the fine grinding station 8 in sequence for rough grinding and fine grinding processes, respectively, which is beneficial to improving the grinding accuracy and mask efficiency of the wafer.

[0034] Optionally, continue to Figure 1 The wafer grinding equipment also includes: a polishing station 9; the polishing station 9 and the fine grinding station 8 are located on the same side of the workbench, and are used for polishing the wafer after fine grinding to reduce burrs or impurities on the wafer surface.

[0035] Optionally, continue to Figure 1 The wafer grinding equipment also includes: a conveying component 5 and a wafer back side cleaning station 3, wherein the conveying component 5 is arranged on one side of the wafer discharge suction cup 6 and the wafer back side cleaning station 3, and is used to convey the polished wafer to the wafer back side cleaning station 3 for back side cleaning.

[0036] Specifically, the polished wafer will return to the position of the wafer discharge suction cup 6 (the wafer discharge suction cup 6 will first rotate clockwise through the bottom, rotate 90 degrees three times, and rotate to the adjacent Figure 1 After the three stations of medium and coarse grinding station 7, fine grinding station 8 and polishing station 9, rotate 270 degrees counterclockwise to return to the adjacent Figure 1 The wafer discharge suction cup 6 is now in the position), at this time, the polished wafer is transferred to the wafer back side cleaning station 3 through the transfer component 5 for back side cleaning.

[0037] Optionally, the wafer grinding equipment further includes: a backlight source 17; the backlight source 17 is arranged on a side of the positioning suction cup 16 away from the wafer discharge suction cup 6, and is used to provide supplementary light when the image recognition device 12 obtains image information of the wafer to be processed.

[0038] Based on the same inventive concept, Figure 7 As shown, an embodiment of the present invention further provides a wafer edge finding and positioning method, based on a wafer grinding device, the wafer grinding device can refer to the content of the aforementioned embodiment, mainly including a control unit 21 and a wafer discharge suction cup 6, a positioning suction cup 16, an image recognition device 12 and a transport component 10 electrically connected to the control unit 21, respectively, the image recognition device 12 is arranged on a workbench, and is used to obtain image information of the wafer to be processed, and the transport component 10 is used to transfer the wafer to be processed from the positioning suction cup 16 along the X-axis direction to the wafer discharge suction cup 6, and the wafer edge finding and positioning method includes the following steps: S100, placing the wafer to be processed on the positioning suction cup 16 and fixing it by adsorption; S200, obtaining the position change of the wafer radius relative to the calibration point through the image recognition device 12, so as to determine the offset between the center of the wafer to be processed and the center of the wafer calibration discharge suction cup; wherein the calibration point is the center position of the calibration wafer when it is placed at the center of the positioning suction cup 16.

[0039] S300, according to the offset between the center of the wafer to be processed and the center of the wafer calibration discharge suction cup, control the positioning suction cup 16 to rotate so that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup 6 is parallel to the X-axis direction.

[0040] S400, determining the offset between the center of the wafer to be processed and the center of the wafer discharge suction cup 6 along the X-axis direction, and controlling the transport component 10 to move the wafer to be processed from the positioning suction cup 16 to the wafer discharge suction cup 6 according to the offset.

[0041] Optionally, while step S200 is being performed, the following steps are also included: S201, controlling the transport assembly 10 to move above the wafer to be processed; S202 , controlling the positioning suction cup 16 to rotate and grabbing the edge-finding mark of the wafer to be processed through the image recognition device 12 to determine the position angle of the edge-finding mark relative to the center of the wafer to be processed.

[0042] Optionally, the edge-finding mark can be a notch or a flat edge on the edge of the wafer. The edge-finding mark is mainly used for aligning the direction of the wafer. The edge-finding positioning is performed by adjusting the position angle of the edge-finding mark relative to the center of the wafer to be processed. During the processing of the wafer, a sensor can be used to uniformly align the edge-finding mark to ensure the consistency of the processing technology.

[0043] In this embodiment, while the wafer is rotating to align its center with the center of the wafer discharge suction cup along the X-axis direction, the wafer edge finding and component handling processes can be performed simultaneously, greatly improving the wafer positioning efficiency.

[0044] Those skilled in the art will appreciate that the various operations, methods, steps, measures, and schemes discussed in the present invention may be alternated, modified, combined, or deleted. Further, other steps, measures, and schemes in the various operations, methods, and schemes discussed in the present invention may also be alternated, modified, rearranged, decomposed, combined, or deleted. Further, the steps, measures, and schemes in the prior art that are similar to those disclosed in the present invention may also be alternated, modified, rearranged, decomposed, combined, or deleted.

[0045] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0046] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0047] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific conditions.

[0048] In the description of this specification, specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. It should be understood that although the steps in the flowchart of the accompanying drawings are displayed in sequence as indicated by the arrows, these steps are not necessarily performed in sequence in the order indicated by the arrows. Unless clearly stated herein, there is no strict order restriction on the execution of these steps, and they may be performed in other orders. Moreover, at least a portion of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but may be performed at different times, and their execution order is not necessarily performed in sequence, but may be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wafer grinding device, comprising: A feeding assembly, a cleaning assembly, and a wafer eccentric positioning assembly, wherein the wafer eccentric positioning assembly comprises: Wafer discharge suction cup, used to place the wafer to be processed after eccentric positioning; A positioning suction cup, the positioning suction cup is used to place the wafer to be processed transferred from the loading platform, and the positioning suction cup is driven to rotate by a rotary drive mechanism; An image recognition device, which is arranged on a workbench and is used to obtain image information of the wafer to be processed, so as to determine the offset between the center of the wafer to be processed and the wafer calibration discharge suction cup along the Y-axis direction; A control unit is electrically connected to the positioning suction cup, the rotation drive mechanism and the image recognition device, and is used to control the rotation drive mechanism to operate according to the offset of the center of the wafer to be processed and the wafer calibration discharge suction cup along the Y-axis direction, so that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup is parallel to the X-axis direction.

2. The wafer grinding equipment according to claim 1, characterized in that: Also includes: A transport assembly, wherein the transport assembly is disposed on the workbench; the transport assembly is connected to an X-axis drive mechanism on the workbench via a Z-axis drive mechanism; The control unit is electrically connected to the X-axis drive mechanism, the Z-axis drive mechanism and the transport component, and is used to control the transport component to transfer the wafer to be processed from the positioning suction cup along the X-axis direction to the wafer discharge suction cup after determining that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup is parallel to the X-axis direction, so as to carry out subsequent grinding process.

3. The wafer grinding equipment according to claim 2, characterized in that: The working frame includes: a frame body and a sliding guide rail installed on the frame body; the frame body and the sliding guide rail both extend along the X-axis direction, the Z-axis driving mechanism and the conveying assembly are both slidably connected to the sliding guide rail through the Z-axis arm, and the Z-axis arm is driven to move along the X-axis direction by the X-axis driving mechanism.

4. The wafer grinding equipment according to claim 2, characterized in that: The rotary drive mechanism is arranged below the positioning suction cup, and the rotary drive mechanism is connected to a rotary joint via a belt, and the upper end of the rotary joint is connected to the positioning suction cup via a rotating shaft, so that the positioning suction cup is driven to rotate by the rotary drive mechanism.

5. The wafer grinding equipment according to claim 2, characterized in that: Also includes: A rough grinding station and a fine grinding station, wherein the rough grinding station and the wafer discharge suction cup are located on the same side of the work frame, and the fine grinding station is located on the other side of the work frame; After eccentric positioning and edge finding, the wafer to be processed passes through the rough grinding station and the fine grinding station in sequence to perform rough grinding and fine grinding processes respectively.

6. The wafer grinding equipment according to claim 5, characterized in that: Also includes: Polishing station; the polishing station and the fine grinding station are located on the same side of the work frame, and are used for polishing the wafer after fine grinding.

7. The wafer grinding equipment according to claim 6, characterized in that: Also includes: A conveying component and a wafer back side cleaning station, wherein the conveying component is arranged on one side of the wafer discharge suction cup and the wafer back side cleaning station, and is used to convey the polished wafer to the wafer back side cleaning station for back side cleaning.

8. The wafer grinding equipment according to claim 2, characterized in that: Also includes: Backlight source; the backlight source is arranged on a side of the positioning suction cup away from the wafer discharge suction cup, and is used to provide supplementary light when the image recognition device obtains image information of the wafer to be processed.

9. A wafer edge-finding and positioning method, based on a wafer grinding device, the wafer grinding device comprises a control unit and a wafer discharge suction cup, a positioning suction cup, an image recognition device and a transport component electrically connected to the control unit respectively, the image recognition device is arranged on a workbench, and is used to obtain image information of the wafer to be processed, and the transport component is used to transfer the wafer to be processed from the positioning suction cup to the wafer discharge suction cup along the X-axis direction, characterized in that: The wafer edge finding and positioning method comprises: S100, placing the wafer to be processed on the positioning suction cup and fixing it by adsorption; S200, obtaining the position change of the wafer radius relative to the calibration point through an image recognition device, so as to determine the offset between the center of the wafer to be processed and the center of the wafer calibration discharge suction cup; wherein the calibration point is the center position of the calibration wafer when it is placed at the center of the positioning suction cup; S300, according to the offset between the center of the wafer to be processed and the center of the wafer calibration discharge suction cup, control the positioning suction cup to rotate so that the line connecting the center of the wafer to be processed and the center of the wafer discharge suction cup is parallel to the X-axis direction; S400, determining the offset between the center of the wafer to be processed and the center of the wafer discharge suction cup along the X-axis direction, and controlling the transport component to move the wafer to be processed from the positioning suction cup to the wafer discharge suction cup according to the offset.

10. The wafer edge finding and positioning method according to claim 9, characterized in that: While step S200 is being performed, it also includes: S201, controlling the transport assembly to move to above the wafer to be processed; S202, controlling the positioning suction cup to rotate and grabbing the edge-finding mark of the wafer to be processed through an image recognition device to determine the position angle of the edge-finding mark relative to the center of the wafer to be processed.

Images