Wafer surface polishing device and polishing method thereof

Abstract

The invention relates to the technical field of wafer processing, in particular to a wafer surface grinding device and a grinding method thereof, and solves the problem that high grinding precision and high grinding efficiency cannot be both considered during wafer surface grinding. The polishing device comprises a workbench, a rotary table, a plurality of polishing pieces, an adjusting assembly, a visual identification piece and a control piece, and the adjusting assembly is configured to enable at least one polishing piece to be close to or far away from a surface to be polished in the vertical direction and enable at least one polishing piece to move in the horizontal direction to be close to or far away from an original point; the control part determines grinding data according to the recognition image and controls the adjusting assembly to drive at least one grinding part to move according to the grinding data, so that one protrusion in the preset area is ground by one grinding part under the condition that the rotary table is static, or at least one protrusion is ground by multiple grinding parts at the same time under the condition that the rotary table rotates. According to the wafer surface grinding device and the grinding method thereof provided by the invention, the grinding precision and the grinding efficiency of the wafer surface can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of wafer processing, and in particular to a wafer surface polishing device and a polishing method thereof. Background Art

[0002] Wafers made of silicon carbide as the main material are widely used in semiconductors, electronics, machinery, chemicals, aerospace and other fields, and the material on the surface of the wafer is used in the electronics industry due to its high temperature resistance, wear resistance, corrosion resistance, high thermal conductivity, high insulation and other properties. For example, it can be used for ultra-large-scale integrated circuit substrates. The quality of the wafer surface has an important impact on its performance and service life. During the preparation of the wafer, there is a polishing process for the wafer surface. However, with the improvement of the quality requirements and production capacity of the wafer surface, the current polishing of the wafer surface cannot meet the requirements of high polishing accuracy and polishing efficiency at the same time. Summary of the invention

[0003] In view of this, the present application provides a wafer surface polishing device and a polishing method thereof, which solves the problem that the surface polishing of the wafer cannot take into account both high polishing accuracy and high polishing efficiency.

[0004] The present application provides a wafer surface grinding device, comprising: a workbench; a turntable, rotatably connected to the workbench, the turntable being configured to carry a wafer, the wafer having a surface to be ground, the turntable having a first axis, the turntable being configured to be able to drive the wafer to rotate around the first axis, the surface to be ground of the wafer carried by the turntable being divided into a plurality of sleeved annular preset areas with a point coincident with the first axis as an origin, at least one of the preset areas having at least one protrusion; a plurality of grinding pieces, movably connected to the workbench, the grinding pieces being configured to grind the protrusions; an adjusting component, disposed on the workbench, the plurality of grinding pieces being connected to the adjusting component, the adjusting component being configured to make at least one of the grinding pieces approach or move away from the surface to be ground in a vertical direction, and to make At least one of the grinding members moves in a horizontal direction to approach or move away from the origin; a visual recognition member is arranged on the workbench, and the visual recognition member is configured to scan each of the preset areas in sequence from the origin to the edge of the wafer, and form an identification image according to the identified protrusions in the scanned preset areas; a control member is communicatively connected with the visual recognition member, the adjustment component and the turntable, and the control member determines grinding data according to the identification image, and controls the adjustment component to drive at least one of the grinding members to move according to the grinding data, so that one of the protrusions in the preset area is ground by one of the grinding members to be flush with the surface to be ground when the turntable is stationary, or at least one of the protrusions is ground by multiple grinding members simultaneously to be flush with the surface to be ground when the turntable is rotating.

[0005] According to a wafer surface polishing device provided in the present application, the control component includes:

[0006] A controller is communicatively connected to the visual recognition member, the adjustment assembly and the turntable; a processor is communicatively connected to the controller, the processor being configured to receive the recognition image and, based on the recognition image, at least obtain the height of each protrusion in the preset area protruding from the surface to be polished and compare it with the preset height, so that the protrusions below or equal to the preset height are polished by multiple polishing members at the same time, and each protrusion above the preset height is polished by one polishing member.

[0007] According to a wafer surface polishing device provided in the present application, the preset height is between 0.2 mm and 0.3 mm.

[0008] According to a wafer surface polishing device provided by the present application, the adjustment component includes: a carrier plate, located above the workbench; a first drive component, connecting the carrier plate and the workbench, the first drive component is configured to drive the carrier plate to approach or move away from the workbench in a vertical direction, and the first drive component is communicatively connected to the control component; a plurality of adjustment blocks, movably connected to the carrier plate, and the plurality of adjustment blocks are arranged in a ring shape around the first axis, and each of the adjustment blocks is connected to one of the polishing pieces; at least one second drive component, connected to the carrier plate, each of the adjustment blocks is connected to one of the second drive components, the second drive component is configured to drive the adjustment block to move in a direction close to or away from the first axis, and each of the second drive components is communicatively connected to the control component respectively.

[0009] According to a wafer surface polishing device provided in the present application, the visual identification component is arranged on the side of the carrier plate facing the workbench, and the geometric center of the identification part of the visual identification component coincides with the orthographic projection of the first axis on the turntable.

[0010] A wafer surface polishing device provided in the present application further includes: a clamping positioning member connected to the turntable, wherein the clamping positioning member is configured to limit the wafer supported by the turntable.

[0011] According to a wafer surface polishing device provided in the present application, the clamping positioning member includes: a carrier, connected to the turntable, the center of the carrier coincides with the first axis, the carrier is provided with a plurality of adsorption holes connected to an external vacuum pump, and the adsorption holes are configured to allow the wafer to be adsorbed on the carrier; a plurality of clamping blocks, slidably connected to the carrier, the plurality of clamping blocks are arranged in a ring around the first axis, and each of the clamping blocks can move in a direction close to or away from the first axis.

[0012] According to a wafer surface polishing device provided by the present application, there is no overlap or partial overlap between any adjacent preset areas.

[0013] In a second aspect, the present application also provides a wafer surface grinding method, which is applied to the wafer surface grinding device described above, wherein the surface to be ground of the wafer takes the point that coincides with the first axis of the turntable of the wafer surface grinding device as the origin, and the wafer surface grinding method comprises: identifying the surface to be ground by a visual identification component, and dividing the surface to be ground into a plurality of nested preset areas with the origin as the center; scanning each of the preset areas in sequence from the origin to the edge of the wafer by the visual identification component, and if at least one protrusion is identified in the scanned preset area, generating an identification image, otherwise continuing to scan the next preset area; the control component receives the identification image and processes the identification image to obtain grinding data, and controls the adjustment component to drive at least one of the grinding parts to move in the vertical direction and / or horizontal direction according to the grinding data, so that one of the protrusions in the preset area is polished by one of the grinding parts to be flush with the surface to be ground when the turntable is stationary, or at least one of the protrusions is polished by multiple of the grinding parts to be flush with the surface to be ground when the turntable is rotating.

[0014] According to a wafer surface polishing method provided by the present application, the control component includes a controller and a processor that are communicatively connected to each other, the control component receives the recognition image and processes the recognition image to obtain polishing data, and controls the adjustment component to drive at least one of the polishing components to move in the vertical direction and / or the horizontal direction according to the polishing data, so that one of the protrusions in the preset area is polished by one of the polishing components to be flush with the surface to be polished when the turntable is stationary, or at least one of the protrusions is polished by multiple of the polishing components to be flush with the surface to be polished when the turntable is rotating, including: the controller receives the recognition image from the visual recognition component The processor receives the recognition image and recognizes the position of each protrusion in the preset area relative to the origin, the size of the protrusion, and compares the height of each protrusion protruding from the surface to be polished with the preset height according to the recognition image, so as to obtain the polishing data, and sends the polishing data to the controller; the controller controls the action of the adjustment component according to the polishing data, so that the protrusions lower than or equal to the preset height are polished by multiple polishing pieces at the same time to be flush with the surface to be polished, and each protrusion higher than the preset height is polished by one polishing piece to be flush with the surface to be polished.

[0015] The present application provides a wafer surface polishing device, in which the surface to be polished of the wafer carried on the turntable is divided into a plurality of nested annular preset areas, and a visual recognition component is used to sequentially recognize each preset area from the origin to the edge of the wafer. If a protrusion is recognized, an identification image is formed, and a control component controls the action of the turntable and the adjustment component according to the situation of the protrusion in the recognition image, so that a larger protrusion is specifically polished by one polishing component, and multiple smaller protrusions can be polished by multiple polishing components at the same time. This method of using a visual recognition component for regional recognition to perform targeted polishing on different protrusions not only avoids the situation where polishing is missed due to the inability of the naked eye to recognize the protrusions, but also the high-precision recognition of the visual recognition component enables all the protrusions on the wafer surface to be recognized, so that different degrees of polishing can be matched to protrusions of different degrees, which is beneficial to improving the polishing accuracy and polishing speed of the protrusions, reducing polishing errors, and thereby improving the polishing accuracy and polishing rate of the wafer surface, thereby improving the wafer production capacity.

[0016] In addition, the surface to be polished of the chip is divided into multiple preset areas and each preset area is scanned in turn by a visual recognition component. When a protrusion is scanned in the preset area, an identification image is formed for subsequent polishing work. When no protrusion is recognized, the next image is scanned, so that the polishing component can be operated to perform targeted polishing only on the preset area with the protrusion, further improving the polishing speed.

[0017] In addition, the present application configures the turntable to be able to rotate or remain stationary according to the specific circumstances of the protrusion to be polished. When a single polishing piece is polishing a larger protrusion, the control piece makes the turntable stationary. When a smaller protrusion is being polished simultaneously by multiple polishing pieces, the control piece controls the turntable to rotate, further improving the polishing speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Shown is a schematic diagram of a wafer surface polishing device provided in the present application.

[0019] Figure 2 Shown is a schematic diagram of the surface to be polished of the wafer provided in the present application.

[0020] Figure 3 Shown is a schematic diagram of a preset area on the surface to be polished of a wafer provided in the present application.

[0021] Figure 4 Shown is a partial structural schematic diagram of a wafer surface polishing device provided in the present application.

[0022] Figure 5 Shown Figure 4 A cross-sectional view of a partial structure of a wafer surface polishing device is shown.

[0023] Figure 6 Shown is a schematic diagram of the turntable portion of a wafer surface polishing device provided in the present application.

[0024] Figure 7 Shown is a flow chart of a wafer surface polishing method provided by the present application.

[0025] Figure 8 Shown is a flow chart of another wafer surface polishing method provided by the present application.

[0026] Reference numerals:

[0027] 1. Workbench; 2. Turntable; 2a. First axis; 21. Drive motor; 3. Grinding piece; 31. Grinding head; 32. Drive unit; 4. Adjustment assembly; 41. First drive assembly; 42. Carrier plate; 43. Adjustment block; 44. Second drive assembly; 441. Motor; 442. Screw nut pair; 5. Clamping and positioning piece; 51. Carrier; 51a. Adsorption hole; 511. Slide groove; 52. Clamping block; 6. Wafer; 61. Surface to be polished; 611. Preset area; 611a. Annular area; 612. Protrusion; 6a. Origin; 7. Visual identification piece. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] The present application provides a wafer surface polishing device, such as Figures 1 to 4 The wafer surface polishing device is used to polish the surface 61 to be polished of the wafer 6. It can be understood that the surface 61 to be polished can be the surface of the wafer 6 used for the integrated circuit, and the surface 61 to be polished can be the surface of at least one side of the wafer 6 in the thickness direction.

[0030] Optionally, the material of the wafer 6 may be graphite, silicon carbide, etc., and the shape of the wafer 6 may be, for example, circular, oval, square, polygonal, etc., and the size of the wafer 6 may also be adjusted according to actual grinding requirements without specific limitation.

[0031] Specifically, the wafer surface grinding device includes a workbench 1, a turntable 2, a plurality of grinding pieces 3 and an adjustment component 4, a visual identification component 7 and a control component. The turntable 2 is rotatably connected to the workbench 1. The turntable 2 is configured to carry a wafer 6. The turntable 2 has a first axis 2a. The turntable 2 is configured to be able to drive the wafer 6 to rotate around the first axis 2a. The surface 61 to be ground of the wafer 6 carried by the turntable 2 is divided into a plurality of nested annular preset areas 611 with the point coinciding with the first axis 2a as the origin 6a, and at least one preset area 611 has at least one protrusion 612; a plurality of grinding pieces 3 are movably connected to the workbench 1, and the grinding pieces 3 are configured to grind the protrusion 612; the adjustment component 4 is arranged on the workbench 1, and the plurality of grinding pieces 3 are connected to the adjustment component 4. The adjustment component 4 is configured to make at least one grinding piece 3 approach or move away from the vertical direction. from the surface 61 to be polished, and to move at least one polishing piece 3 in the horizontal direction to approach or move away from the origin 6a; the visual recognition piece 7 is arranged on the workbench 1, and the visual recognition piece 7 is configured to scan each preset area 611 in sequence from the origin 6a to the edge of the wafer 6, and form an identification image according to the identified protrusion 612 in the scanned preset area 611; the control piece is communicated with the visual recognition piece 7, the adjustment component 4 and the turntable 2, the control piece determines the polishing data according to the identification image, and controls the adjustment component 4 to drive at least one polishing piece 3 to move according to the polishing data, so that a protrusion 612 in the preset area 611 is polished by one polishing piece 3 to be flush with the surface 61 to be polished when the turntable 2 is stationary, or at least one protrusion 612 is polished by multiple polishing pieces 3 simultaneously to be flush with the surface 61 to be polished when the turntable 2 is rotating.

[0032] Optionally, the visual recognition component 7 can be, for example, a camera, which can specifically include a recognition unit and a pan-tilt head, wherein the recognition unit is used to capture images of the surface to be polished 61, and the recognition unit is detachably connected to the workbench 1 via the pan-tilt head. In other embodiments, the visual recognition component 7 can also be other devices capable of capturing images, without specific limitation.

[0033] Optionally, the turntable 2 is connected to a driving motor 21, and the driving motor 21 is in communication connection with a control component, and the control component can control the driving motor 21 to start or stop, so as to drive the turntable 2 to rotate or stop rotating around the first axis 2a.

[0034] In the embodiment of the present application, the surface 61 to be polished of the wafer 6 carried on the turntable 2 is divided into a plurality of nested annular preset areas 611, and the visual recognition component 7 is used to sequentially recognize each preset area 611 from the origin 6a to the edge of the wafer 6. If a protrusion 612 is recognized, a recognition image is formed, and the control component controls the action of the turntable 2 and the adjustment component 4 according to the situation of the protrusion 612 in the recognition image, so that a larger protrusion 612 is targetedly polished by one polishing component 3, and multiple protrusions 612 of smaller size and located in the same preset area 611 can be polished by multiple polishing components at the same time. The polishing of the polishing part 3, which uses the visual recognition part 7 to perform regional identification so as to perform targeted polishing on different protrusions 612, not only avoids the situation where polishing is missed due to the inability of the naked eye to identify the protrusions 612, but the high-precision recognition of the visual recognition part 7 enables all the protrusions 612 on the surface of the chip 6 to be identified, so that different degrees of polishing can be matched with protrusions 612 of different degrees, which is beneficial to improve the polishing accuracy and polishing speed of the protrusions 612, reduce the polishing error, and further improve the polishing accuracy and polishing rate of the surface of the chip 6, thereby improving the production capacity of the chip 6.

[0035] In addition, the surface 61 to be polished of the chip 6 is divided into a plurality of preset areas 611 and each preset area 611 is scanned in turn by the visual recognition component 7, and when a protrusion 612 is scanned in the preset area 611, an identification image is formed for subsequent polishing work, and when the protrusion 612 is not recognized, the next image is scanned, so that the polishing component 3 can be operated to perform targeted polishing only on the preset area 611 with the protrusion 612, thereby further improving the polishing speed.

[0036] In addition, the present application configures the turntable 2 to be able to rotate or remain stationary according to the specific circumstances of the protrusion 612 to be polished. When a single polishing piece 3 is polishing a larger protrusion 612, the control piece makes the turntable 2 stationary. When a smaller protrusion 612 is being polished simultaneously by multiple polishing pieces 3, the control piece controls the turntable 2 to rotate, thereby further improving the polishing speed.

[0037] It is understandable that the protrusion 612 of the surface to be polished 61 identified by the visual identification member 7 may be a burr, an oxide layer protruding partially from the surface, or other defects, which are not specifically limited. For the sake of easy observation, Figure 2 and Figure 3 In the figure, a circle with a black shadow and a circle without a black shadow are used to indicate the protrusion 612 , and a dotted line is used as an edge dividing the preset area 611 .

[0038] In an optional embodiment, the grinding member 3 may include a connected driving portion 32 and a grinding head 31, the driving portion 32 is in communication with the control member, and the driving portion 32 can drive the grinding head 31 to rotate around its own axis, and the axis of the grinding head 31 is parallel to the first axis 2a. In addition, a grinding surface is provided on the side of the grinding head 31 facing the turntable 2, and the grinding surface is used to contact with the protrusion 612 to be polished in the surface 61 to be polished and realize the polishing of the protrusion 612 through the rotation of the grinding head 31.

[0039] It is understandable that the grinding surface of the grinding head 31 can be a plane or an arc surface, and the size and shape of the grinding surface can be adaptively adjusted according to the actual grinding needs. In the present application, the grinding surface can be set as a circular plane, and the diameter of the circle can be adaptively adjusted according to the actual needs without specific limitation.

[0040] Optionally, the number of the plurality of preset areas 611 into which the wafer 6 is divided and the area of ​​each preset area 611 can be adaptively adjusted according to the actual size of the wafer 6 carried by the turntable 2. In addition, the division of the plurality of preset areas 611 of the wafer 6 can be realized by the visual recognition member 7. For example, after the wafer 6 is loaded onto the turntable 2, the visual recognition member 7 can first recognize the area of ​​the surface of the wafer 6 as a whole, and divide the radius from the origin 6a to the edge of the wafer 6 into N equal parts, and each equal part is circled to form a plurality of preset areas 611.

[0041] Optionally, among the divided multiple preset areas 611, there is no overlap between any adjacent preset areas 611 to avoid repeated scanning. Alternatively, adjacent preset areas 611 may partially overlap to avoid the protrusion 612 at the edge of the preset area 611 from being easily missed.

[0042] In some embodiments, the control member includes a controller and a processor, the controller is communicatively connected to the visual recognition member 7, the adjustment component 4 and the turntable 2; the processor is communicatively connected to the controller, and the processor is configured to receive a recognition image, and at least obtain the height of each protrusion 612 in the preset area 611 protruding from the surface to be polished 61 based on the recognition image and compare it with the preset height, so that the protrusions 612 below or equal to the preset height are polished by multiple polishing members 3 at the same time, and each protrusion 612 above the preset height is polished by one polishing member 3.

[0043] It can be understood that the preset height is used as a reference height pre-input into the processor, and all protrusions 612 in the preset area 611 are classified according to their height, and all protrusions 612 above the preset height are classified as the first group (indicated by circles without black shadows in the figure), and the protrusions 612 below or equal to the preset height are classified as the second group (indicated by circles with black shadows in the figure). The processor calculates the size, height, distance to the origin 6a and other relevant data of the protrusions 612 in each group to form polishing data.

[0044] Optionally, the preset height is between 0.2 mm and 0.3 mm. For example, the preset height may be 0.2 mm, 0.25 mm, or 0.3 mm. In the embodiment of the present application, the preset height is set to 0.3 mm, and can be adaptively adjusted according to actual needs.

[0045] For example, Figure 3 , in the recognition image formed by a preset area 611, a total of 9 protrusions 612 are recognized. The processor calculates the height, size, and distance to the origin 6a of the 9 protrusions 612 according to the recognition image, and compares the height of the 9 protrusions 612 with the preset height of 0.3mm, and divides the 2 protrusions 612 higher than the preset height into the first group, and the other protrusions 612 lower than or equal to the preset height into the second group, and calculates the relevant data of the protrusions 612 in each group to obtain the grinding data and send it to the controller. Afterwards, the controller grinds the protrusions 612 in the first group with a larger height difference by one grinding piece 3 for one protrusion 612 according to the grinding data, and grinds the protrusions 612 in the second group with a smaller height difference by multiple grinding pieces 3 at the same time.

[0046] Optionally, when grinding the protrusions 612 in the first group, the controller can control the multiple grinding heads 31 to move to positions corresponding to different protrusions 612 respectively, so that the multiple grinding heads 31 grind the multiple protrusions 612 in the first group respectively to increase the grinding speed.

[0047] In addition, before grinding the protrusions 612 in the second group, the processor can further divide the multiple protrusions 612 in the second group according to the diameter of the grinding head 31 and the distance from the multiple protrusions 612 in the second group to the origin 6a. When the distances from the multiple grinding heads 31 to the origin 6a are the same, when the turntable 2 rotates, the grinding surface forms an annular area 611a in the direction of the positive projection of the turntable 2, so that the preset area 611 can be further divided into at least one annular area 611a, and multiple grinding heads 31 are used to simultaneously grind multiple protrusions 612 in the same annular area 611a.

[0048] Optionally, the protrusions 612 in the plurality of annular regions 611 a may be polished sequentially toward the edge of the wafer 6 with the origin 6 a as the center to avoid the situation of missing polishing.

[0049] In an optional embodiment, when grinding multiple protrusions 612 in the same annular area 611a, the processor will first calculate the height of each protrusion 612 in the annular area 611a, and adjust the distance between the multiple grinding heads 31 and the surface 61 to be grinded in the vertical direction according to the lowest protrusion 612 to ensure the grinding accuracy of the multiple protrusions 612 in the annular area 611a.

[0050] In an optional embodiment, before grinding multiple protrusions 612 in the same annular area 611a, when it is identified that the annular area 611a includes a first group of protrusions 612, the controller will control the grinding piece 3 to first perform targeted grinding on the first group of protrusions 612 to a height lower than or equal to a preset height, and then control the multiple grinding heads 31 to grind all the protrusions 612 in the annular area 611a at the same time, so as to avoid the risk of irregular fracture at the contact position between the protrusions 612 and the surface 61 to be grinded when multiple grinding heads 31 grind protrusions 612 with higher heights.

[0051] Optionally, when the grinding head 31 first performs targeted grinding on the first group of protrusions 612, the first group of protrusions 612 can be ground to be flush with the surface 61 to be ground, or can be ground to be lower than or equal to a preset height. Adaptive adjustments can be made according to actual needs without specific limitations.

[0052] It is understandable that the processor may include an edge calculator that can be used to calculate the height, size and distance to the origin 6a of the protrusion 612 in the recognition image for data analysis, so as to obtain the grinding height, grinding area and grinding time of the grinding piece 3 for different protrusions 612.

[0053] Optionally, when the visual recognition member 7 completes scanning of each preset area 611, it indicates that the first grinding of the surface to be polished 61 is completed. The visual recognition member 7 further includes scanning each preset area 611 for a second time in sequence from the origin 6a to the edge of the wafer 6, and repeating the above operation until each preset area 611 can no longer identify the protrusion 612 and stops.

[0054] In some embodiments, Figure 4 and Figure 5The adjustment component 4 includes a carrier plate 42, a first drive component 41, a plurality of adjustment blocks 43 and at least one second drive member, the carrier plate 42 is located above the workbench 1; the first drive component 41 connects the carrier plate 42 and the workbench 1, the first drive component 41 is configured to drive the carrier plate 42 to approach or move away from the workbench 1 in a vertical direction, and the first drive component 41 is communicated with the control member; the adjustment block 43 is movably connected to the carrier plate 42, and the plurality of adjustment blocks 43 are arranged in a ring around the first axis 2a, and each adjustment block 43 is connected to a grinding member 3; the second drive component 44 is connected to the carrier plate 42, each adjustment block 43 is connected to a second drive component 44, the second drive component 44 is configured to drive the adjustment block 43 to move in a direction close to or away from the first axis 2a, and each second drive component 44 is respectively communicated with the control member. The vertical movement of one or more grinding heads 31 and the horizontal movement close to or away from the origin 6a can be adjusted according to the situation of the protrusion 612 to be polished, so that one protrusion 612 can be polished or multiple protrusions 612 can be polished simultaneously according to the needs, which is easy to control.

[0055] It can be understood that the first driving component 41 may include a driving cylinder and a guide member, the driving cylinder is arranged on the workbench 1, the driving cylinder is communicated with the control member, the push rod of the driving cylinder extends in the vertical direction and is connected to the carrier plate 42, the guide member includes a guide shaft and a guide sleeve that cooperate in the vertical direction, one of the guide shaft and the guide sleeve is arranged on the workbench 1, and the other is arranged on the carrier plate 42, and the movement of the push rod driven by the driving cylinder in the vertical direction can drive the carrier plate 42 to approach or move away from the workbench 1 in the vertical direction.

[0056] Optionally, the second drive assembly 44 includes a motor 441 and a connected lead screw nut pair 442, the motor 441 is in communication with the control member, the lead screw nut pair 442 includes a screw connected to the output end of the motor 441, a nut is threadedly connected to the screw, and the adjustment block 43 is fixedly connected to the nut. The motor 441 can drive the screw to rotate, thereby driving the nut to move along the axis of the screw, so that the distance from each adjustment block 43 to the origin 6a can be adjusted separately.

[0057] Optionally, the visual identification component 7 is arranged on the side of the carrier 42 facing the workbench 1, and the geometric center of the identification part of the visual identification component 7 on the turntable 2 coincides with the orthographic projection of the first axis 2a on the turntable 2, so as to improve the accuracy and stability of identifying the surface 61 to be polished of the chip 6.

[0058] In some embodiments, Figure 6The wafer surface grinding device also includes a clamping positioning member 5, which is connected to the turntable 2. The clamping positioning member 5 is configured to limit the wafer 6 carried by the turntable 2 to ensure that when multiple protrusions 612 are ground simultaneously, the wafer 6 can rotate smoothly with the turntable 2 to avoid the wafer 6 from shifting during the rotation process.

[0059] Specifically, the clamping positioning member 5 includes a carrier 51 and a plurality of clamping blocks 52. The carrier 51 is connected to the turntable 2. The center of the carrier 51 coincides with the first axis 2a. The carrier 51 is provided with a plurality of adsorption holes 51a connected to an external vacuum pump. The adsorption holes 51a are configured to allow the wafer 6 to be adsorbed on the carrier 51. The carrier 51 is provided with a plurality of slide grooves 511. The clamping blocks 52 are slidably connected to the slide grooves 511 of the carrier 51. The plurality of clamping blocks 52 are arranged in a ring around the first axis 2a. Each clamping block 52 can move in a direction close to or away from the first axis 2a. The combined positioning method using the adsorption positioning of the adsorption holes 51a and the clamping positioning of the clamping blocks 52 can ensure the clamping stability while allowing the surface 61 to be polished of the wafer 6 to be fully exposed. It can be applicable to the clamping and fixing of wafers 6 of different shapes, sizes and thicknesses, and can be applicable to the clamping and positioning of different wafers 6.

[0060] The present application also provides a wafer surface polishing method, which is applied to the wafer surface polishing device described in the above embodiments, such as Figure 7 and Figure 8 , the wafer surface polishing method comprises the following steps:

[0061] S81, identifying the surface 61 to be polished by the visual recognition member 7, and dividing the surface 61 to be polished into a plurality of nested preset areas 611 with the origin 6a as the center.

[0062] It can be understood that the division of the preset area 611 in the surface to be polished 61 can refer to the relevant description in the above-mentioned wafer surface polishing device, and will not be repeated here.

[0063] S82, scan each preset area 611 in sequence from the origin 6a to the edge of the wafer 6 through the visual recognition component 7, if at least one protrusion 612 is recognized in the scanned preset area 611, generate a recognition image, otherwise continue to scan the next preset area 611.

[0064] It can be understood that the visual recognition member 7 can recognize the protrusions 612 in the surface 61 to be polished that cannot be recognized by the naked eye, thereby improving the recognition precision and accuracy.

[0065] S83. The control component receives the recognition image and processes the recognition image to obtain grinding data, and controls the adjustment component 4 to drive at least one grinding component 3 to move in the vertical direction and / or horizontal direction according to the grinding data, so that a protrusion 612 in the preset area 611 is grinded by one grinding component 3 to be flush with the surface to be grinded 61 when the turntable 2 is stationary, or at least one protrusion 612 is grinded by multiple grinding components 3 simultaneously to be flush with the surface to be grinded 61 when the turntable 2 is rotating.

[0066] The wafer polishing method provided in the embodiment of the present application utilizes the visual recognition component 7 to sequentially identify each preset area 611 toward the edge of the wafer 6 with the origin 6a as the center. If a protrusion 612 is identified, an identification image is formed. The control component controls the action of the turntable 2 and the adjustment component 4 according to the situation of the protrusion 612 in the identification image, so that a larger protrusion 612 is specifically polished by one polishing component 3, and multiple protrusions 612 with smaller sizes and located in the same annular area 611a can be polished by multiple polishing components 3 at the same time. This method of using the visual recognition component 7 for regional recognition to perform targeted polishing of different protrusions 612 can match different polishing methods to different protrusions 612, thereby realizing small-area targeted polishing of protrusions 612 in different positions, which is beneficial to improving the polishing accuracy and polishing speed of the surface 61 to be polished and reducing polishing errors.

[0067] In an optional embodiment, step S83 specifically includes:

[0068] S831. The controller receives the recognition image from the visual recognition component 7 and sends the recognition image to the processor.

[0069] S832, the processor receives the recognition image, and identifies the position of each protrusion 612 in the preset area 611 relative to the origin 6a, the size of the protrusion 612, and compares the height of each protrusion 612 protruding from the surface to be polished 61 with the preset height according to the recognition image, obtains the polishing data, and sends the polishing data to the controller.

[0070] S833, the controller controls the action of the adjustment component 4 according to the grinding data, so that the protrusions 612 below or equal to the preset height are simultaneously grinded by multiple grinding pieces 3 to be flush with the surface to be grinded 61, and each protrusion 612 above the preset height is grinded by one grinding piece 3 to be flush with the surface to be grinded 61.

[0071] It is understandable that before sending the grinding data to the controller, all the protrusions 612 in the preset area 611 can also be classified according to the result of comparing the height of each protrusion 612 protruding from the surface 61 to be grinded with the preset height, and the multiple protrusions 612 higher than the preset height are regarded as the first group, and the multiple protrusions 612 lower than or equal to the preset height are regarded as the second group. The preset area 611 is further divided into at least one annular area 611a, and it is identified in turn whether the multiple protrusions 612 in each annular area 611a only include the protrusions 612 of the second group. If so, multiple grinding heads 31 are used to grind the multiple protrusions 612 at the same time. Otherwise, one grinding head 31 is used to grind the protrusions 612 of the first group first, and then multiple grinding heads 31 are used to grind the protrusions 612 in the annular area 611a at the same time. For details, please refer to the relevant descriptions in the above embodiments and will not be repeated here.

[0072] The phrases "one embodiment", "an embodiment", etc. mentioned in the specification indicate that the embodiment described may include a specific feature, structure or characteristic, but not every embodiment may include the specific feature, structure or characteristic. In addition, such phrases do not necessarily refer to the same embodiment. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it is within the knowledge of those skilled in the art to implement such feature, structure or characteristic in conjunction with other embodiments, whether explicitly or not explicitly described.

[0073] It should be understood that “on,” “above,” and “over” in this disclosure should be interpreted in the broadest manner, so that “on” not only means “directly on something,” but also includes the meaning of “on something” with intervening features or layers therebetween, and “above” or “over” not only includes the meaning of “above” or “over,” but also may include the meaning of “above” or “over something” with no intervening features or layers therebetween (i.e., directly on something).

[0074] Additionally, spatially relative terms, such as "below," "below," "beneath," "above," "above," etc., may be used herein for ease of description to describe the relationship of one component or feature to other components or features as shown in the figures. The spatially relative terms are intended to encompass different orientations of the component in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein may likewise be interpreted accordingly.

[0075] It should be noted that, in this application, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0076] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A wafer surface polishing device, characterized in that: include: Workbench; A turntable, rotatably connected to the workbench, the turntable is configured to carry a wafer, the wafer has a surface to be polished, the turntable has a first axis, the turntable is configured to drive the wafer to rotate around the first axis, the surface to be polished of the wafer carried by the turntable is divided into a plurality of sleeved annular preset areas with a point coincident with the first axis as an origin, at least one of the preset areas has at least one protrusion; A plurality of grinding pieces, movably connected to the workbench, the grinding pieces being configured to grind the protrusions; an adjusting assembly disposed on the workbench, the plurality of grinding pieces being connected to the adjusting assembly, the adjusting assembly being configured to move at least one of the grinding pieces closer to or farther from the surface to be grinded in a vertical direction, and to move at least one of the grinding pieces in a horizontal direction to move closer to or farther from the origin; A visual recognition member disposed on the workbench, the visual recognition member being configured to sequentially scan each of the preset areas from the origin toward the edge of the wafer, and to form a recognition image in the scanned preset areas according to the recognized protrusions; A control member is communicatively connected with the visual recognition member, the adjustment member and the turntable, the control member determines grinding data according to the recognition image, and controls the adjustment member to drive at least one of the grinding members to move according to the grinding data, so that one of the protrusions in the preset area is grinded by one of the grinding members to be flush with the surface to be grinded when the turntable is stationary, or at least one of the protrusions is grinded by multiple of the grinding members simultaneously to be flush with the surface to be grinded when the turntable is rotating.

2. The wafer surface polishing device according to claim 1, characterized in that: The control element comprises: a controller, in communication with the visual identification member, the adjustment assembly and the turntable; A processor is communicatively connected to the controller, and is configured to receive the recognition image, and to obtain at least the height of each protrusion in the preset area protruding from the surface to be polished based on the recognition image and compare it with the preset height, so that the protrusions below or equal to the preset height are polished by multiple polishing pieces at the same time, and each protrusion above the preset height is polished by one polishing piece.

3. The wafer surface polishing device according to claim 2, characterized in that: The preset height is between 0.2 mm and 0.3 mm.

4. The wafer surface polishing device according to claim 1, characterized in that: The adjustment component comprises: A carrier plate, located above the workbench; A first driving component is connected to the carrier plate and the workbench, the first driving component is configured to drive the carrier plate to approach or move away from the workbench in a vertical direction, and the first driving component is in communication with the control component; A plurality of adjustment blocks are movably connected to the carrier plate, and the plurality of adjustment blocks are arranged in a ring shape around the first axis, and each of the adjustment blocks is connected to one of the grinding pieces; At least one second drive component is connected to the carrier plate, each of the adjustment blocks is connected to a second drive component, the second drive component is configured to drive the adjustment block to move toward or away from the first axis, and each of the second drive components is respectively communicated with the control component.

5. The wafer surface polishing device according to claim 4, characterized in that: The visual identification member is disposed on a side of the carrier plate facing the workbench, and an orthographic projection of a geometric center of an identification portion of the visual identification member on the turntable coincides with an orthographic projection of the first axis on the turntable.

6. The wafer surface polishing device according to any one of claims 1 to 5, characterized in that: Also includes: A clamping positioning member is connected to the turntable, and the clamping positioning member is configured to limit the wafer carried by the turntable.

7. The wafer surface polishing device according to claim 6, characterized in that: The clamping positioning member comprises: A carrier connected to the turntable, the center of the carrier coincides with the first axis, the carrier is provided with a plurality of adsorption holes connected to an external vacuum pump, and the adsorption holes are configured to allow the wafer to be adsorbed on the carrier; A plurality of clamping blocks are slidably connected to the carrier, the plurality of clamping blocks are arranged in a ring shape around the first axis, and each of the clamping blocks can move toward or away from the first axis.

8. The wafer surface polishing device according to any one of claims 1 to 5, characterized in that: Any adjacent preset areas have no overlap or partial overlap.

9. A method for polishing a wafer surface, characterized in that: The wafer surface polishing device according to any one of claims 1 to 8 is applied, wherein the surface of the wafer to be polished has a point that coincides with the first axis of the turntable of the wafer surface polishing device as an origin, and the wafer surface polishing method comprises: Identify the surface to be polished by a visual recognition element, and divide the surface to be polished into a plurality of preset areas that are connected with each other with the origin as the center; Scanning each of the preset areas in sequence from the origin to the edge of the wafer by the visual recognition element, if at least one protrusion is recognized in the scanned preset area, generating a recognition image, otherwise continuing to scan the next preset area; The control component receives the recognition image and processes the recognition image to obtain grinding data, and controls the adjustment component to drive at least one of the grinding components to move in the vertical direction and / or the horizontal direction according to the grinding data, so that one of the protrusions in the preset area is grinded by one of the grinding components to be flush with the surface to be grinded when the turntable is stationary, or at least one of the protrusions is grinded by multiple grinding components simultaneously to be flush with the surface to be grinded when the turntable is rotating.

10. The wafer surface polishing method according to claim 9, characterized in that: The control component includes a controller and a processor that are communicatively connected to each other, the control component receives the recognition image and processes the recognition image to obtain grinding data, and controls the adjustment component to drive at least one of the grinding components to move in a vertical direction and / or a horizontal direction according to the grinding data, so that one of the protrusions in the preset area is ground by one of the grinding components to be flush with the surface to be ground when the turntable is stationary, or at least one of the protrusions is ground by multiple grinding components simultaneously to be flush with the surface to be ground when the turntable is rotating, including: The controller receives the identification image from the visual identification member and sends the identification image to the processor; The processor receives the recognition image, and identifies the position of each protrusion in the preset area relative to the origin, the size of the protrusion, and compares the height of each protrusion protruding from the surface to be polished with a preset height according to the recognition image, to obtain the polishing data, and sends the polishing data to the controller; The controller controls the action of the adjustment component according to the grinding data, so that the protrusions below or equal to the preset height are simultaneously grinded by multiple grinding pieces until they are flush with the surface to be grinded, and each of the protrusions above the preset height is grinded by one grinding piece until it is flush with the surface to be grinded.

Images