A silicon wafer edge polishing system

Abstract

The application discloses a silicon wafer edge polishing system, relates to the technical field of silicon wafer polishing, and is used for polishing the side of a silicon wafer. The side of the silicon wafer comprises an inclined A surface, an inclined B surface, a vertical edge side M surface connecting the A surface and the B surface, and the side of the silicon wafer is provided with a V-shaped notch. The silicon wafer edge polishing system comprises sequentially connected conveying modules, deviation correction and centering modules, silicon wafer edge polishing modules, two groups of silicon wafer inclined surface polishing modules, overturning modules, silicon wafer V-shaped notch polishing modules and cleaning modules. The deviation correction and centering modules establish a process reference by dynamically adjusting the center of the silicon wafer. The edge polishing modules drive a first polishing pad to press against the edge of the silicon wafer to realize friction polishing by adopting a cover setting type polishing drum assembly. The V-shaped notch polishing modules adjust the notch inclination angle by using a swing plate and cooperate with a polishing wheel assembly to realize radial feeding polishing. The setting significantly improves the polishing efficiency and yield of large-size silicon wafers.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silicon wafer polishing, in particular to a silicon wafer edge polishing system. BACKGROUND

[0002] The current large-size silicon wafer edge polishing field faces serious technical bottlenecks, domestic enterprises have long relied on imported equipment or directly purchased polished finished products, and the existing equipment mainly adopts fixed trajectory mechanical grinding method for processing the edge of the silicon wafer, which is difficult to adapt to the complex curvature change of the 8-12 inch silicon wafer edge, especially cannot meet the differentiated polishing precision requirements of the TOP surface, A / B surface and V-shaped notch; in the traditional process, the positioning of the silicon wafer relies on static mechanical limiting, and the positioning error causes uneven contact pressure between the polishing drum and the edge of the silicon wafer, resulting in inconsistent polishing depth, and the V-shaped notch polishing needs to manually adjust the angle of the silicon wafer repeatedly, which is low in efficiency and easy to cause edge collapse defects.

[0003] The above technical defects further lead to difficulty in multi-process cooperation, because of the lack of high-precision dynamic positioning capability, the pose reference of the silicon wafer cannot be unified between the edge polishing and notch polishing processes, forcing each link to be calibrated independently, which greatly reduces the production efficiency, at the same time, the absence of adaptive polishing mechanism for irregular edge makes it difficult for the polishing drum to fit the curved profile of the silicon wafer, resulting in polishing blind area, and the separation design of the directional polishing module of the V-shaped notch further increases the complexity of the equipment.

[0004] In the face of the challenges of variable curvature of large silicon wafer edge and stress sensitivity of V-shaped notch, the market urgently needs an integrated equipment integrating dynamic positioning, centrifugal self-adaptive pressure application and notch directional polishing. SUMMARY

[0005] The main purpose of the present application is to provide a silicon wafer edge polishing system, which aims to solve the problem of difficult polishing of large silicon wafer side.

[0006] To achieve the above purpose, the present application provides a silicon wafer edge polishing system for polishing the side of a silicon wafer, the side of the silicon wafer includes an inclined A surface, an inclined B surface and a vertical edge side M surface connecting the A surface and the B surface, and the side of the silicon wafer is provided with a V-shaped notch, the polishing system comprises:

[0007] A conveying module sequentially connects each module and transports the silicon wafer;

[0008] A deviation correction and centering module, which includes a deviation correction assembly and a centering assembly arranged thereon, the centering assembly drives the silicon wafer to lift and rotate in the Z direction, and cooperates with the deviation correction assembly to establish a process reference coordinate system;

[0009] A silicon wafer edge polishing module comprises a mounting assembly, a polishing drum assembly and a first polishing pad, the polishing drum assembly is covered outside the mounting assembly, the mounting assembly fixes the silicon wafer, the inner wall of the polishing drum assembly fixes the first polishing pad to contact the side M surface of the silicon wafer, and the polishing drum assembly is driven to rotate to drive the first polishing pad to press and rub the edge side M surface of the silicon wafer;

[0010] Two sets of silicon wafer inclined surface polishing modules, which comprise a bearing table capable of reverse rotation and a polishing rotating assembly, the polishing rotating assembly is located above the bearing table, and the polishing rotating assembly vertically presses and rotates in the same direction on the inclined surface of the silicon wafer;

[0011] A turnover module is arranged between the two sets of silicon wafer inclined surface polishing modules to turn the silicon wafer to a preset angle;

[0012] A silicon wafer V-shaped notch polishing module comprises a polishing wheel assembly and a swing plate, the swing plate carries the silicon wafer and adjusts the V-shaped notch angle of the silicon wafer through swing to cooperate with the polishing wheel assembly to perform radial feeding polishing on the V-shaped notch;

[0013] A cleaning module is used to clean and dry the polished silicon wafer.

[0014] The present application has the beneficial effects that: the present application establishes a unified process reference coordinate system through the deviation correction and centering module, ensures the accurate coincidence of the center of the silicon wafer and the rotating shaft, eliminates the uneven polishing caused by the positioning deviation, the silicon wafer edge polishing module adopts the polishing drum assembly with centrifugal pressure, so that the first polishing pad adaptively presses the edge curved surface of the silicon wafer, improves the edge polishing integrity and efficiency, the double silicon wafer inclined surface polishing module cooperates with the turnover module to realize the automatic polishing of the double inclined surface of the silicon wafer, avoids the surface damage caused by manual turnover, the V-shaped notch polishing module dynamically adjusts the posture through the swing plate and combines with the radial feeding polishing, accurately controls the notch polishing angle and force, reduces the edge collapse risk, finally, the modules are connected through the conveying module to form a full-process automatic polishing flow path, greatly reduces the manual intervention, and synchronously improves the production capacity and yield. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only show some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the drawings shown.

[0016] Figure 1 It is a schematic diagram of the three-dimensional structure of the silicon wafer edge polishing system in the present application.

[0017] Figure 2 Fig. 1 is a schematic diagram of the structure of a silicon wafer edge polishing system according to the present application;

[0018] Figure 3 Fig. 2 is a schematic diagram of the structure of a deviation correction and centering module according to the present application;

[0019] Figure 4 Fig. 3 is a schematic diagram of the structure of a deviation correction and centering module according to the present application from another angle;

[0020] Figure 5 Fig. 4 is a schematic diagram of the structure of a silicon wafer edge polishing module according to the present application (without the mounting assembly);

[0021] Figure 6 Fig. 5 is a sectional view of a silicon wafer edge polishing module according to the present application (without the mounting assembly);

[0022] Figure 7 Fig. 6 is a schematic diagram of the structure of a silicon wafer inclined surface polishing module according to the present application (without the polishing bearing assembly);

[0023] Figure 8 Fig. 7 is a sectional view of a silicon wafer inclined surface polishing module according to the present application (without the polishing bearing assembly);

[0024] Figure 9 Fig. 8 is a schematic diagram of the structure of a turnover module according to the present application;

[0025] Figure 10 Fig. 9 is a sectional view of a turnover module according to the present application;

[0026] Figure 11 Fig. 10 is a schematic diagram of the structure of a silicon wafer V-shaped notch polishing module according to the present application;

[0027] Figure 12 Fig. 11 is a schematic diagram of the structure of a silicon wafer V-shaped notch polishing module according to the present application from another angle;

[0028] Figure 13 Fig. 12 is a schematic diagram of the structure of a cleaning module according to the present application;

[0029] Figure 14 Fig. 13 is a schematic diagram of the structure of a silicon wafer edge polishing system according to the present application;

[0030] Figure 15 Fig. 14 is a schematic diagram of the structure of a windowing module according to the present application;

[0031] Figure 16 Fig. 15 is a schematic diagram of the structure of a material taking module according to the present application;

[0032] Figure 17 Fig. 16 is a sectional view of a silicon wafer according to the present application.

[0033] Reference signs:

[0034] 100, polishing box; 200, loading basket;

[0035] 1, conveying module; 11, material taking module; 111, manipulator; 112, control box; 113, second sliding rail; 12, first sliding rail; 13, transporting module;

[0036] 2, deviation rectifying and centering module; 21, deviation rectifying assembly; 211, mounting plate; 2111, first guide rail; 2112, first screw rod; 2113, notch; 212, first driving element; 213, moving plate; 2131, first nut; 2132, first sliding block; 22, centering assembly; 221, support plate; 2211, limiting support; 22111, limiting opening; 222, rotating shaft; 223, tray; 2231, adsorption hole; 2232, limiting block; 224, second driving element; 225, third driving element;

[0037] 3, silicon wafer edge polishing module; 31, mounting assembly; 311, mounting table; 312, first waterproof cover; 32, polishing drum assembly; 321, polishing drum upper plate; 3211, sliding groove; 322, polishing drum lower plate; 323, centrifugal pushing element; 3231, telescopic block; 32311, movable groove; 3232, gravity ball; 3233, connecting rod; 32331, connecting groove; 3234, first movable shaft; 3235, second movable shaft; 324, connecting shaft; 325, surrounding plate; 33, first polishing tile; 34, fourth driving element; 35, first driving main shaft;

[0038] 4, silicon wafer inclined surface polishing module; 41, bearing table; 42, polishing rotating assembly; 421, fifth driving element; 422, second driving main shaft; 423, rotating disc; 4231, second polishing tile; 43, second waterproof cover;

[0039] 5, overturning module; 51, guide rail assembly; 511, second guide rail; 512, eighth driving element; 513, second screw rod; 514, second nut; 52, sixth driving element; 53, clamping mounting plate; 54, clamping mechanism; 541, seventh driving element; 542, material taking clamping plate; 5421, first section; 5422, second section; 5423, third section; 543, swinging air claw;

[0040] 6, silicon wafer V-shaped notch polishing module; 61, swinging plate; 611, notch groove; 62, polishing wheel assembly; 621, notch polishing wheel; 622, ninth driving element; 63, V-shaped polishing bottom plate; 631, third guide rail; 632, tenth driving element; 64, waterproof cover; 65, support seat; 66, eleventh driving element;

[0041] 7, cleaning module; 71, cleaning platform; 72, third waterproof cover; 73, water spraying block;

[0042] 8, window opening module; 81, door opening mounting plate; 82, window opening finger; 83, twelfth driving element; 84, thirteenth driving element; 85, fourth guide rail.

[0043] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0045] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications also change accordingly.

[0046] In addition, if the embodiments of the present application involve descriptions of "first", "second", etc., the descriptions of "first", "second", etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing throughout the text is that it includes three parallel schemes, taking "A and / or B" as an example, which includes A scheme, or B scheme, or A and B schemes. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of a person skilled in the art, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the scope of protection claimed by the present application.

[0047] The present application provides a silicon wafer edge polishing system for polishing the side of a silicon wafer, the side of the silicon wafer includes an inclined A surface, an inclined B surface, and a vertical edge side M surface connecting the A surface and the B surface, and the side of the silicon wafer is provided with a V-shaped notch, please refer to Figures 1-17The polishing system includes a conveying module 1, which sequentially connects various modules and transports silicon wafers; a centering and alignment module 2, which includes a centering component 22 mounted on a centering component 21; the centering component 22 drives the silicon wafer to move and rotate in the Z-axis and, in conjunction with the centering component 21, establishes a process reference coordinate system; a silicon wafer edge polishing module 3, which includes a mounting component 31, a polishing drum assembly 32, and a first polishing tile 33; the polishing drum assembly 32 is mounted outside the mounting component 31, which fixes the silicon wafer; the first polishing tile 33 is fixed to the inner wall of the polishing drum assembly 32 and contacts the side M-surface of the silicon wafer; the polishing drum assembly 32 rotates to drive the first polishing tile 33 to press against the side M-surface of the silicon wafer edge for friction polishing; and two sets of silicon wafer tilting surface polishing modules 4, each set of silicon wafer tilting surface polishing modules... The inclined surface polishing module 4 includes a support platform 41 capable of reverse rotation and a polishing rotation component 42. The polishing rotation component 42 is located above the support platform 41. The polishing rotation component 42 presses vertically against the inclined surface of the silicon wafer and rotates in the same direction. The flipping module 5 is set between the two silicon wafer inclined surface polishing modules 4 to flip the silicon wafer to a preset angle. The silicon wafer V-notch polishing module 6 includes a polishing wheel assembly 62 and a swing plate 61. The swing plate 61 carries the silicon wafer and adjusts the V-notch angle of the silicon wafer by swinging to cooperate with the polishing wheel assembly 62 to radially feed and polish the V-notch. Finally, the cleaning module 7 cleans and dries the polished silicon wafer. This equipment, through the cooperation of multiple modules, fully automates the polishing of the side of large silicon wafers, greatly reducing manual intervention and simultaneously improving production capacity and yield.

[0048] It should be noted that in this embodiment, the size of the large silicon wafer to be polished is 8-12 inches. Please refer to [reference needed] for the X, Y, and Z directions. Figure 2 Regarding the inclined surfaces A and B on the side of the silicon wafer, and the side surface M connecting the vertical edges of surfaces A and B, please refer to... Figure 17 .

[0049] In this embodiment, please refer to Figures 2-4 The centering and correction module 2 also includes a light curtain sensor (not shown). The light curtain sensor is electrically connected to the centering and correction component 21. The light curtain sensor acquires the center position of the silicon wafer in the rotating state to trigger the centering and correction component 21 to correct the spin.

[0050] The deviation correction assembly 21 comprises a mounting plate 211, a first driving element 212 and a moving plate 213. The mounting plate 211 is provided with a first guide rail 2111 in the Y direction and a first screw rod 2112 in the Y direction. The first driving element 212 is connected to the first screw rod 2112 at the driving end. The moving plate 213 is provided with a first nut 2131 at the bottom to engage the first screw rod 2112 and a first sliding block 2132 at the top to slide along the first guide rail 2111. When the first driving element 212 drives the first screw rod 2112 to rotate, the first nut 2131 moves on the first screw rod 2112 accordingly, thereby driving the moving plate 213 to move in the Y direction along the first guide rail 2111. The above arrangement is mainly to adjust the position of the silicon wafer, so that the silicon wafer positioning in the subsequent process is accurate, and uniform polishing is better achieved.

[0051] As for the centering assembly 22, the centering assembly 22 comprises a support plate 221, a rotating shaft 222, a tray 223, a second driving element 224 and a third driving element 225. The support plate 221 is fixedly connected above the moving plate 213. The rotating shaft 222 penetrates through the support plate 221 and is connected to the second driving element 224 at the driving end at the bottom and is fixedly connected to the tray 223 provided with vacuum holes at the top. The rotating shaft 222 is hollow inside and is provided with an adsorption element which is in communication with adsorption holes 2231 on the surface of the tray 223. The adsorption element is mainly used to adsorb the silicon wafer placed on the tray 223, so as to fix the silicon wafer on the tray 223 without damaging the silicon wafer. At the same time, it is also convenient for the subsequent rotation of the tray 223, reduces the situation of the silicon wafer being thrown out, and avoids causing material waste and safety accidents.

[0052] Actually, in order to further enhance the stability of the silicon wafer on the tray 223, the tray 223 is also provided with a plurality of upwardly inclined limiting blocks 2232, and the support plate 221 is provided with a plurality of limiting supports 2211 at the top. The plurality of limiting blocks 2232 are uniformly distributed at the edges of the tray 223, and the plurality of limiting supports 2211 are uniformly distributed at the edges of the support plate 221. One side of the limiting support 2211 facing the axis of the rotating shaft 222 is provided with a limiting opening 22111. When the silicon wafer is deviated from the predetermined position due to the centrifugal effect, the silicon wafer is prevented from deviating from the predetermined position due to the double action of the limiting blocks 2232 and the limiting supports 2211. It should be noted that the limiting blocks 2232 of the tray 223 can pass through the limiting opening 22111 during the rotation of the tray 223.

[0053] In the embodiment, the second driving element 224 drives the rotating shaft 222 to lift along the Z direction to make the tray 223 receive or release the silicon wafer. The third driving element 225 drives the rotating shaft 222 to rotate, thereby driving the tray 223 to rotate the silicon wafer to cooperate with the light curtain sensor to scan the center of the silicon wafer. In order to ensure that the centering assembly 22 can move smoothly with the moving plate 213, the mounting plate 211 is also provided with a slot 2113 for the movement of the centering assembly 22.

[0054] Regarding the working principle of the deviation correction and centering module 2, the conveying module 1 places the polished silicon wafer on the tray 223, in the process, the second driving element 224 drives the rotating shaft 222 to rise to receive the silicon wafer, at this time, the suction assembly starts to operate, the silicon wafer is sucked by the suction hole 2231, the second driving element 224 drives the rotating shaft 222 to descend to the designated position, the third driving element 225 drives the rotating shaft 222 to rotate, the silicon wafer is driven to rotate through the rotation of the tray 223, it should be noted that the light curtain sensor is arranged on the mounting plate 211, in the process of rotating the silicon wafer, the light curtain sensor emits a parallel laser beam covering the edge of the rotating silicon wafer, and the edge point coordinate sequence is collected in real time, the offset between the actual center of the silicon wafer and the theoretical rotating center of the equipment is calculated, and the deviation correction assembly 21 receives the data and performs corresponding operation, the first driving element 212 rotates the screw rod, so that the moving plate 213 slides on the first guide rail 2111, and the dynamic coincidence of the geometric center of the silicon wafer and the axis of the rotating shaft 222 is realized, so that the constant gap between the edge polishing drum and the silicon wafer is ensured, the uniform pressure distribution of the plane polishing wheel is ensured, and the accurate matching of the V-shaped notch polishing track is ensured.

[0055] In other words, the light curtain sensor combines the dynamic deviation correction mechanism to correct the center deviation of the silicon wafer in real time, ensures the accuracy of the process reference, and avoids the displacement or flying of the silicon wafer during high-speed rotation through the double protection of the suction cooperation limiting block 2232 and the support of the tray 223, improves the positioning stability and safety, and lays a foundation for subsequent uniform polishing.

[0056] In the embodiment, please refer to Figure 2 、 Figures 5-6 , the silicon wafer edge polishing module 3 further comprises a fourth driving element 34 and a first driving main shaft 35 connected with the driving end of the fourth driving element 34, and the polishing drum assembly 32 comprises a polishing drum upper plate 321, a polishing drum lower plate 322 and a plurality of centrifugal pushing elements 323, wherein the polishing drum upper plate 321 is connected with the first driving main shaft 35, the polishing drum upper plate 321 and the polishing drum lower plate 322 are fixedly connected through a plurality of connecting shafts 324, the centrifugal pushing elements 323 are slidably connected at both ends of the polishing drum upper plate 321 and the polishing drum lower plate 322, and the centrifugal pushing elements 323 are located between adjacent connecting shafts 324, when the fourth driving element 34 drives the first driving main shaft 35 to rotate, the polishing drum assembly 32 will rotate, and then the centrifugal pushing elements 323 slide to the axis direction of the first driving main shaft 35, so as to push the first polishing tile 33 to extrude the side M surface of the silicon wafer.

[0057] In order to achieve the polishing of the silicon wafer, the silicon wafer edge polishing module 3 needs to be connected with the polishing liquid, specifically, the polishing drum lower plate 322 is a ring-shaped plate, in other words, the polishing drum upper plate 321, the first polishing tile 33 and the polishing drum lower plate 322 constitute a hollow cavity, and the hollow cavity is connected with the polishing liquid inlet, in this embodiment, the polishing liquid is poured from the end of the first driving main shaft 35 located in the hollow cavity.

[0058] Further, when the polishing drum assembly 32 rotates at high speed, the center of gravity ball 3232 on the centrifugal pushing element 323 is displaced radially outward under the action of centrifugal force, and pushes the telescopic block 3231 to slide along the sliding groove 3211 of the polishing drum upper plate 321 and the lower plate to the direction of the silicon wafer through the connecting rod 3233, one end of the connecting rod 3233 is hinged to the surrounding plate 325 through the second movable shaft 3235, and the other end is hinged to the movable groove 32311 of the telescopic block 3231 through the first movable shaft 3234, the double movable shaft structure converts the radial movement of the center of gravity ball 3232 into the linear displacement of the telescopic block 3231, and drives the first polishing tile 33 fixedly connected with the telescopic block 3231 to press the edge of the silicon wafer, obviously, when the rotation speed of the polishing drum increases, the centrifugal force increases, and the pressure of the first polishing tile 33 increases accordingly, realizing self-adaptive pressure polishing, when the rotation speed decreases, the center of gravity ball 3232 resets, and the telescopic block 3231 retreats to release the pressure, forming a dynamic pressure regulation closed loop.

[0059] In order to achieve the polishing of the silicon wafer, the silicon wafer edge polishing module 3 needs to be connected with the polishing liquid, specifically, the polishing drum lower plate 322 is a ring-shaped plate, in other words, the polishing drum upper plate 321, the first polishing tile 33 and the polishing drum lower plate 322 constitute a hollow cavity, and the hollow cavity is connected with the polishing liquid inlet, in this embodiment, the polishing liquid is poured from the end of the first driving main shaft 35 located in the hollow cavity.

[0060] To strengthen the polishing effect of the edge of the silicon wafer, the silicon wafer edge polishing module 3 further comprises a first ultrasonic assembly (not shown), which is integrated in the first driving main shaft 35 in this embodiment, and the high-frequency vibration is directly transmitted to the polishing interface through coaxial rigid conduction, and a "dynamic pressure + high-frequency micro-impact" composite polishing mechanism is formed with the polishing liquid and the centrifugal pushing element 323, thereby well solving the problem of brittle collapse of the edge of a large silicon wafer.

[0061] In this embodiment, the mounting assembly 31 comprises a mounting table 311 capable of lifting and rotating and a first waterproof cover 312 arranged around the mounting table 311. The first waterproof cover 312 is arranged to prevent the polishing liquid from splashing out and polluting other modules, and can also accommodate broken silicon wafers due to operation errors. The mounting table 311 is arranged to be capable of lifting and rotating through lifting elements (not shown) and rotating elements (not shown). The arrangement is mainly to facilitate the reception of the silicon wafer and the polishing of the side M surface of the silicon wafer in cooperation with the polishing drum assembly 32. The lifting elements and rotating elements belong to the prior art and should be known by those skilled in the art, and will not be described in detail here.

[0062] As to the working principle of the silicon wafer edge polishing module 3, after the mounting table 311 receives the silicon wafer through the conveying module 1, the mounting table 311 is lifted by the lifting elements, so that the mounting table 311 rises and the silicon wafer is located in the hollow cavity of the polishing drum assembly 32, and the inner wall of the first polishing pad 33 is in contact with the side M surface of the silicon wafer. Then the rotating elements and the fourth driving element 34 are started at the same time, so that the mounting table 311 and the polishing drum assembly 32 are rotated in opposite directions. In the rotating process of the polishing drum assembly 32, the first ultrasonic assembly also operates at the same time. Under the cooperation of the polishing drum assembly 32 and the first ultrasonic assembly, the side M surface of the silicon wafer can be quickly polished.

[0063] In this embodiment, please refer to Figure 2 , Figures 7-8 Each silicon wafer inclined surface polishing module 4 further comprises a second waterproof cover 43, and the polishing rotating assembly 42 in each silicon wafer inclined surface polishing module 4 comprises a fifth driving element 421, a second driving main shaft 422 and a rotating disc 423. The second waterproof cover 43 is arranged around the bearing table 41. The second waterproof cover 43 is arranged to prevent the polishing liquid from splashing out and polluting other modules, and can also accommodate broken silicon wafers due to operation errors. As to the second driving main shaft 422, one end of the second driving main shaft 422 is connected with the driving end of the fifth driving element 421, and the other end is connected with the rotating disc 423. The rotating disc 423 is located directly above the bearing table 41. The rotating disc 423 is provided with a second polishing pad 4231 which is in contact with the silicon wafer inclined surface. The second polishing pad 4231 is used for polishing the A surface or the B surface of the silicon wafer inclined surface placed on the bearing table 41 by rotating.

[0064] In order to achieve the polishing of the inclined surface of the silicon wafer, the silicon wafer inclined surface polishing module 4 also needs to be connected with the polishing liquid. Specifically, the rotating disc 423 also has a hollow cavity, and the hollow cavity is connected with the polishing liquid inlet. In this embodiment, the polishing liquid is poured from the end of the second driving spindle 422 in the hollow cavity.

[0065] In order to strengthen the polishing effect of the edge of the silicon wafer, the silicon wafer inclined surface polishing module 4 further comprises a second ultrasonic assembly (not shown). In this embodiment, the second ultrasonic assembly is integrated in the second driving spindle 422. The high-frequency vibration is directly transmitted to the polishing interface through the coaxial rigid conduction, and the polishing liquid, the polishing rotating assembly 42 also forms a composite polishing mechanism of "dynamic pressure + high-frequency micro-impact", which further improves the polishing efficiency.

[0066] As for the rotating bearing table 41, the bearing table 41 can be rotated through another rotating element. The setting is mainly convenient for receiving the silicon wafer and cooperating with the polishing rotating assembly 42 to polish the inclined surface of the silicon wafer. The lifting element also belongs to the prior art, and those skilled in the art should know that it will not be elaborated here.

[0067] As for the working principle of the first group of silicon wafer inclined surface polishing modules 4, after the silicon wafer is fixed on the bearing table 41, the fifth driving element 421 drives the second driving spindle 422, drives the rotating disc 423 at the bottom to descend and rotate, so that the second polishing pad 4231 installed at the bottom of the rotating disc 423 is attached to the inclined surface A of the silicon wafer. The second polishing pad 4231 applies polishing pressure to the inclined surface A in the vertical direction of the inclined surface A. At this time, the bearing table 41 and the rotating disc 423 rotate synchronously, but the rotating directions are opposite. At this time, the polishing liquid is injected from the end of the second driving spindle 422 through the hollow cavity of the rotating disc 423 and flows to the polishing interface of the silicon wafer. At this time, the second ultrasonic assembly integrated in the second driving spindle 422 is also started synchronously, and the high-frequency vibration is directly transmitted to the polishing area through the coaxial rigid conduction of the spindle. At this time, the rotation of the bearing table 41, the rotation and pressure of the second polishing pad 4231 driven by the rotating disc 423, the continuous injection of the polishing liquid and the high-frequency micro-impact vibration jointly act on the polishing of the inclined surface A of the silicon wafer. During the entire polishing process, the second waterproof cover 43 surrounding the bearing table 41 always works to prevent the polishing liquid from splashing and polluting other modules and to collect possible broken silicon wafers.

[0068] Obviously, the above design utilizes the reverse rotation of the bearing table 41 and the rotating disc 423 to enhance the surface shear force, cooperates with the ultrasonic vibration and the continuous polishing liquid injection to realize the efficient and low-damage inclined surface polishing. In addition, the second waterproof cover 43 has the functions of splash-proof and fragment collection, which can maintain the reliability of the system.

[0069] Further, please refer to Figure 2 ,Figures 9-10 The turnover module 5 comprises a guide rail assembly 51, a sixth driving element 52, a Z-direction clamping mounting plate 53 and a clamping mechanism 54. The clamping mounting plate 53 is moved between the two sets of silicon wafer inclined surface polishing modules 4 through the guide rail assembly 51. The sixth driving element 52 drives the clamping mechanism 54 to move up and down on the clamping mounting plate 53. The clamping mechanism 54 comprises a seventh driving element 541 and a clamping element. The seventh driving element 541 drives the clamping element to turn over and turn over to a preset angle, which is 180 degrees in this embodiment. The above setting is mainly to exchange the top and bottom of the silicon wafer, in other words, to turn over the silicon wafer so that the inclined surface B of the silicon wafer is polished by the second set of silicon wafer inclined surface polishing module 4, thereby ensuring that the inclined surface A and the inclined surface B of the silicon wafer are both polished.

[0070] As described above, the two sets of silicon wafer inclined surface polishing modules 4 are arranged side by side. The guide rail assembly 51 is located between the side parts of the two sets of silicon wafer inclined surface polishing modules 4. The guide rail assembly 51 comprises a second guide rail 511, an eighth driving element 512, a second lead screw 513 and a second nut 514. The bottom of the clamping mounting plate 53 is connected with the second nut 514. The second nut 514 engages with the second lead screw 513. The top of the clamping mounting plate 53 is provided with a second sliding block which is slidingly fitted with the second guide rail 511. When the eighth driving element 512 drives the second lead screw 513 to rotate, the second nut 514 will move on the second lead screw 513 accordingly, thereby driving the clamping mounting plate 53 to move on the second guide rail 511. The above setting is mainly to transport the silicon wafer to the second set of silicon wafer inclined surface polishing module 4.

[0071] During the transportation of the silicon wafer, the silicon wafer needs to be turned over. In this embodiment, the seventh driving element 541 comprises a swing air claw 543. The clamping element comprises two material taking clamping plates 542. The swing air claw 543 is connected with the two material taking clamping plates 542 to realize the opening, clamping and overall rotation of the two material taking clamping plates 542. The material taking clamping plate 542 comprises a continuous first section 5421, a second section 5422 and a third section 5423. The first section 5421 is a straight rod. The top and bottom of the straight rod are provided with at least two clamping jaws. The clamping jaws on the two material taking clamping plates 542 are correspondingly matched, so that the silicon wafer can be clamped. Then the swing air claw 543 controls the clamping, so that the silicon wafer is stably clamped by the clamping element. In order to avoid the damage of the silicon wafer by the material taking clamping plate 542, the second section 5422 is an arc-shaped rod which conforms to the edge of the silicon wafer. The third section 5423 is also a straight rod which is used to be connected with the swing air claw 543.

[0072] Further, after the clamping element stably clamps the silicon wafer, the clamping element slides on the clamping mounting plate 53 under the cooperation of the sixth driving element 52 to reach a position where the clamping element can be turned over.

[0073] Regarding the working principle of the turnover module 5, when the silicon wafer completes the processing of the first set of silicon wafer inclined face polishing module 4, the eighth driving element 512 in the guide rail assembly 51 drives the second lead screw 513 to rotate, so that the second nut 514 engaged with the lead screw drives the clamping mounting plate 53 to move to the silicon wafer position along the second guide rail 511. At this time, the two material taking clamping plates 542 of the clamping element are opened under the control of the swing gas claw 543, and the corresponding clamping jaws on the first section 5421 of the straight rod accurately clamp the silicon wafer, and the second section 5422 of the arc-shaped rod is attached to the edge of the silicon wafer to avoid damage. Then the clamping mounting plate 53 continues to slide on the second guide rail 511, and after sliding to the corresponding position, the sixth driving element 52 pushes the clamping element to slide on the clamping mounting plate 53 to the turnover station, and then the swing gas claw 543 controls the two sets of material taking clamping plates 542 to turn over, realizing the requirement of silicon wafer surface change. Finally, it is transported to the second set of silicon wafer inclined face polishing module 4 for polishing. The above design avoids pollution or damage caused by manual intervention, and improves yield and productivity.

[0074] In this embodiment, please refer to Figure 2 、 Figures 11-12 , the V-shaped notch polishing module 6 of the silicon wafer includes a V-shaped polishing bottom plate 63 and a water-proof cover 64, wherein the V-shaped polishing bottom plate 63 is provided with a support seat 65 for supporting the swing plate 61 to swing at the top thereof, the water-proof cover 64 is arranged on the top of the V-shaped polishing bottom plate 63 and surrounds the swing plate 61, and the polishing wheel assembly 62 is slidably arranged on the top of the V-shaped polishing bottom plate 63 and located at the V-shaped notch side of the silicon wafer. Specifically, the polishing wheel assembly 62 includes a notch polishing wheel 621 and a ninth driving element 622 for driving the notch polishing wheel 621 to operate. In addition, the V-shaped polishing bottom plate 63 is provided with a third guide rail 631 and a tenth driving element 632, and the tenth driving element 632 drives the polishing wheel assembly 62 to slide on the second guide rail 511, so as to adjust the distance between the notch polishing wheel 621 in the polishing wheel assembly 62 and the swing plate 61. The support plate 221 is rotatably arranged, and the support seat 65 is provided with an eleventh driving element 66 for driving the swing plate 61 to swing around the axis of the notch polishing wheel 621. The support plate 221 is provided with a notch groove 611 for positioning the V-shaped notch of the silicon wafer.

[0075] Regarding the working principle of the V-shaped notch polishing module 6 of the silicon wafer, the silicon wafer is placed on the swing plate 61 through the conveying module 1. At this time, the V-shaped notch of the silicon wafer is located above the notch groove 611. The eleventh driving element 66 drives the swing plate 61 to swing, thereby adjusting the inclination angle of the V-shaped notch, so as to facilitate the radial polishing of the V-shaped notch by the notch polishing wheel 621. When the inclination angle of the V-shaped notch is adjusted, the notch polishing wheel 621 polishes the V-shaped notch by sliding on the V-shaped polishing bottom plate 63.

[0076] Further, please refer to Figures 1-2 、 Figures 14-16The conveying module 1 comprises a material taking module 11, a first sliding rail 12 arranged at the side of each module, and a plurality of conveying modules 13 sliding along different sections of the first sliding rail 12 to transport the silicon wafers. In the embodiment, the conveying module 13 is similar to the turnover module, with the difference that the two material taking clamps in the conveying module 13 clamp and release the silicon wafers along the Y direction, and the clamping element in the conveying module 13 cannot be turned over.

[0077] In the embodiment, the polishing system further comprises a polishing box 100 in which each module is accommodated, one side of the polishing box 100 is provided with a plurality of loading baskets 200, and the polishing box 100 is provided with a window opening module 8 for opening and closing the corresponding basket door. The window opening module 8 mainly cooperates with the material taking module 11. When the material taking module 11 does not take materials, the window opening module 8 is in a stationary state, at which time the loading basket 200 is in a closed state to avoid the internal stored silicon wafers from being affected by external factors. When the material taking module 11 needs to take the silicon wafers to be polished, the window opening module 8 opens the basket door, and the material taking module 11 can take materials in the corresponding loading basket 200.

[0078] As to the window opening module 8, the window opening module 8 comprises a door opening mounting plate 81, a window opening finger 82, a twelfth driving element 83, a thirteenth driving element 84, and a fourth guide rail 85. The twelfth driving element 83 drives the door opening mounting plate 81 to stretch and retract along the X direction, the thirteenth driving element 84 drives the window opening finger 82 mounted on the door opening mounting plate 81 to rotate, so that the window opening finger 82 is connected with the basket door. When the door opening mounting plate 81, the window opening finger 82, the twelfth driving element 83, and the thirteenth driving element 84 cooperate to grasp the basket door, the above-mentioned overall structure is slid along the Z direction in the fourth guide rail 85, so that the loading basket 200 is in a material taking state. The above-mentioned window opening module 8 is fully automated and does not need manual operation. In the operation process, the window opening module 8 will not collide with the silicon wafers, and in the process of grasping the basket door and transferring the basket door, the silicon wafers will not be damaged, which has strong protection and convenience.

[0079] As to the material taking module 11, the material taking module 11 comprises a robot 111, a control box 112, and a Y direction second sliding rail 113. The control box 112 slides along the second sliding rail 113 and controls the robot 111 to clamp and transport the silicon wafers to the deviation correction and centering module 2. It should be noted that in the embodiment, there are four loading baskets 200. When the robot 111 takes materials, only the silicon wafers in one loading basket 200 are all taken out, and then the robot 111 slides to the next loading basket 200 through the second sliding rail 113 to take materials. As to the specific structure of the robot 111, the robot 111 belongs to the prior art, and those skilled in the art should know it.

[0080] In the embodiment, please refer to Figure 2 andFigure 13 The cleaning module comprises a cleaning table 71 capable of lifting and rotating, a water spraying block 73, and a third waterproof cover 72, the third waterproof cover 72 is arranged around the cleaning table 71, and the water spraying block 73 is used for spraying water on the silicon wafer placed on the cleaning table 71 to realize cleaning of the silicon wafer.

[0081] Specifically, in the embodiment, each driving element can be a cylinder or a motor, as long as the corresponding structure driving state can be met.

[0082] Regarding the operation process of the silicon wafer edge polishing system: the wafer is taken out from the loading basket 200 by the taking module 11, is sent to the tray 223 of the deviation correction and centering module 2 through the conveying module 13, and after the wafer is fixed by the adsorption assembly, the light curtain sensor scans the edge of the wafer in rotation, triggers the deviation correction assembly 21 to dynamically adjust the coincidence of the wafer center and the rotating shaft 222, establishes a process reference, and then the wafer enters the edge polishing module, the mounting table 311 lifts the wafer to the hollow cavity of the polishing drum, the reverse-rotating polishing drum assembly 32 drives the first polishing pad 33 to press the edge side M surface of the wafer through the centrifugal pushing mechanism, cooperates with the first ultrasonic wave assembly and the injected polishing liquid to complete efficient polishing of the edge side M surface of the wafer, and the polished wafer is conveyed to the first group of wafer inclined surface polishing modules 4, the bearing table 41 cooperates with the reverse-rotating rotating disc 423 to pressurize, the second ultrasonic wave assembly and the polishing liquid cooperatively polish the inclined surface A of the wafer, the clamping mechanism 54 of the turnover module 5 accurately grabs the wafer, moves to the turnover work position along the guide rail, rotates 180°, and then sends the wafer to the second group of wafer inclined surface polishing modules 4 to complete polishing of the inclined surface B of the wafer, then the wafer enters the wafer V-shaped gap polishing module 6, the swing plate 61 carries the wafer and adjusts the inclination angle of the V-shaped gap, and the polishing wheel assembly 62 radially feeds to precisely polish the V-shaped gap, at this time, the edge side of the wafer is polished, finally, the cleaning module 7 cleans and dries the wafer, and the full-process automatic processing is completed.

[0083] The above is only an optional embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation made according to the content of the present application specification and drawings, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.

Claims

1. A silicon wafer edge polishing system for polishing a side portion of a silicon wafer, the side portion of the silicon wafer including an inclined A surface, an inclined B surface, and a vertical edge side M surface connecting the A surface and the B surface, and the side portion of the silicon wafer being provided with a V-shaped notch, characterized in that, The polishing system comprises: a conveying module sequentially connecting each module and transporting the silicon wafer; a deviation correction and centering module comprising a deviation correction assembly and a centering assembly arranged thereon, the centering assembly driving the silicon wafer to vertically lift and rotate, and cooperating with the deviation correction assembly to establish a process reference coordinate system; a silicon wafer edge polishing module comprising a mounting assembly, a polishing drum assembly and a first polishing pad, the polishing drum assembly being arranged outside the mounting assembly, the mounting assembly fixing the silicon wafer, the inner wall of the polishing drum assembly fixing the first polishing pad to contact the side M surface of the silicon wafer, the polishing drum assembly rotating to drive the first polishing pad to press against the side M surface of the silicon wafer for frictional polishing; two sets of silicon wafer inclined surface polishing modules, each comprising a reversely rotatable bearing table and a polishing rotating assembly, the polishing rotating assembly being arranged above the bearing table, the polishing rotating assembly vertically pressing against the inclined surface of the silicon wafer and rotating in the same direction; a turnover module arranged between the two sets of silicon wafer inclined surface polishing modules and turning the silicon wafer to a preset angle; a silicon wafer V-shaped notch polishing module comprising a polishing wheel assembly and a swing plate, the swing plate bearing the silicon wafer and adjusting the V-shaped notch angle of the silicon wafer through swinging to cooperate with the polishing wheel assembly for radial feed polishing of the V-shaped notch; a cleaning module cleaning and drying the polished silicon wafer; the deviation correction and centering module further comprises a light curtain sensor, the light curtain sensor being electrically connected with the deviation correction assembly, the light curtain sensor acquiring the center position of the silicon wafer in the rotating state to trigger the deviation correction assembly to correct deviation; the deviation correction assembly comprises a mounting plate, the centering assembly comprises a support plate, a rotating shaft, a tray, a second driving element and a third driving element, the support plate being fixed above a movable plate movable along the Y direction, the rotating shaft being arranged through the support plate, the bottom of the rotating shaft being connected with the driving end of the second driving element, the top of the rotating shaft being fixed with the tray provided with a vacuum hole, the hollow cavity inside the rotating shaft being provided with an adsorption element, the adsorption element being in communication with the adsorption holes on the surface of the tray, the second driving element driving the rotating shaft to vertically lift and lower to make the tray receive or release the silicon wafer, the third driving element driving the rotating shaft to rotate, driving the tray to rotate the silicon wafer to cooperate with the light curtain sensor to scan the center of the silicon wafer; the silicon wafer edge polishing module further comprises a fourth driving element and a first driving main shaft connected with the driving end of the fourth driving element; the polishing drum assembly comprises a polishing drum upper plate, a polishing drum lower plate and a plurality of centrifugal pushing elements, the polishing drum upper plate being connected with the first driving main shaft, the polishing drum upper plate and the polishing drum lower plate being fixedly connected through a plurality of connecting shafts, the centrifugal pushing elements being slidably connected to the polishing drum upper plate and the polishing drum lower plate at both ends, and the centrifugal pushing elements being located between adjacent connecting shafts. The centrifugal pushing element comprises a telescopic block and a gravity center ball matching the number of the telescopic block, the polishing drum upper plate and the polishing drum lower plate are both provided with a sliding groove, and the two ends of the telescopic block are respectively slidingly inserted into the corresponding sliding grooves; A surrounding plate is arranged between the edge side of the polishing drum upper plate and the polishing drum lower plate, the surrounding plate is arranged opposite to the telescopic block, the surrounding plate is rotationally provided with a connecting rod, one end of the connecting rod is connected with the gravity center ball, and the other end of the connecting rod penetrates through the surrounding plate and abuts against the telescopic block, and the telescopic block is connected with the first polishing tile.

2. The silicon wafer edge polishing system of claim 1, wherein, The deviation correction assembly further comprises a first driving element and a moving plate, the mounting plate is provided with a Y-direction first guide rail and a Y-direction first screw rod, the first driving element is connected with the first screw rod at a driving end, the moving plate is provided with a first nut at a bottom portion to engage with the first screw rod, and the moving plate is provided with a first sliding block at a top portion to slidingly fit the first guide rail, and the first driving element drives the first screw rod to rotate to drive the first nut to drive the moving plate to move in the Y-direction along the first guide rail.

3. The silicon wafer edge polishing system of claim 1, wherein, The mounting assembly comprises a mounting table capable of lifting and rotating and a first waterproof cover, and the first waterproof cover is arranged around the mounting table.

4. The silicon wafer edge polishing system of claim 1, wherein, The silicon wafer inclined surface polishing module further comprises a second waterproof cover, and the polishing rotating assembly comprises a fifth driving element, a second driving main shaft and a rotating disc, the second waterproof cover is arranged around the bearing table, one end of the second driving main shaft is connected with the driving end of the fifth driving element, and the other end of the second driving main shaft is connected with the rotating disc, the rotating disc is located directly above the bearing table, and the rotating disc is provided with a second polishing tile in contact with the silicon wafer inclined surface.

5. The silicon wafer edge polishing system of claim 1, wherein, The turnover module comprises a guide rail assembly, a sixth driving element, a Z-direction clamping mounting plate and a clamping mechanism, the clamping mounting plate is moved between the two groups of silicon wafer inclined surface polishing modules through the guide rail assembly, and the sixth driving element drives the clamping mechanism to move up and down on the clamping mounting plate. The clamping mechanism comprises a seventh driving element and a clamping element, the seventh driving element drives the clamping element to turn over to clamp the silicon wafer, so as to exchange the top and bottom of the silicon wafer.

6. The silicon wafer edge polishing system of claim 1, wherein, The silicon wafer V-shaped notch polishing module comprises a V-shaped polishing bottom plate and a waterproof cover; The V-shaped polishing bottom plate is provided with a support seat at a top portion to support the swing of the swing plate, the waterproof cover is arranged on the top of the V-shaped polishing bottom plate and surrounds the swing plate, and the polishing wheel assembly is slidingly arranged on the top of the V-shaped polishing bottom plate and located at the V-shaped notch side of the silicon wafer.

7. The silicon wafer edge polishing system of claim 1, wherein, The conveying module comprises a material taking module, a first sliding rail and a plurality of conveying modules, the sliding rail is arranged on the side of each module, and the plurality of conveying modules slidingly convey the silicon wafers along different sections of the sliding rail. The material taking module comprises a mechanical hand, a control box and a Y-direction second sliding rail, the control box slidingly moves along the second sliding rail and controls the mechanical hand to clamp and convey the silicon wafer to the deviation correction and centering module.

8. The silicon wafer edge polishing system of claim 1, wherein, The polishing system further comprises a polishing box, each module is accommodated in the polishing box, one side of the polishing box is provided with a plurality of charging baskets, and the polishing box is provided with a window opening module for opening and closing the corresponding basket door.

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