Loading cup and using method thereof, wafer polishing device and processing equipment

Abstract

The invention relates to a loading cup, a using method thereof, a wafer polishing device and processing equipment. The loading cup comprises a height-adjustable wafer placing frame, the wafer placing frame is used for placing wafers and providing an operation channel, the loading cup is further integrated with a wafer overturning assembly, the wafer overturning assembly is arranged on the periphery of the wafer placing frame and comprises a lifting mechanism and a wafer clamping mechanism installed on the lifting mechanism, the lifting mechanism is used for lifting the wafer clamping mechanism, and the wafer clamping mechanism is used for clamping the wafers. When the wafer clamping mechanism is aligned with the wafer placing rack, the wafer clamping mechanism can enter the operation channel in the radial direction to clamp the wafer and rotates to turn over the wafer after the wafer clamping mechanism is lifted by the lifting mechanism. The polishing head cleaning assembly can penetrate through the operation channel in the axial direction to clean the wafer polishing head. The loading cup is provided with the polishing head cleaning assembly, and the wafer polishing head can be cleaned more conveniently through the device, so that crystals on the polishing head are reduced, and the wafer polishing quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wafer post-processing, and more specifically, to a loading cup and a method for using the same, a wafer polishing device and a processing equipment. Background Art

[0002] During the CMP (chemical mechanical polishing) process, the polishing liquid remains on the polishing head and forms crystals on the outer ring and edge of the air film of the polishing head. Therefore, preventive maintenance is required to clean the polishing head every once in a while. However, since the polishing liquid continuously forms crystals on the polishing head, if it is not cleaned in time, it is not conducive to the maintenance of the polishing head and also affects the post-cleaning effect of CMP. Summary of the invention

[0003] In view of this, the present invention provides a loading cup and a method for using the same, and a wafer polishing device, so as to solve or at least alleviate one or more of the above-mentioned problems and other problems existing in the prior art.

[0004] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides a loading cup, wherein the loading cup comprises a wafer placement rack capable of adjusting the height, a wafer flipping assembly and a polishing head cleaning assembly, the wafer placement rack is used to place wafers, the wafer placement rack provides an operation channel, the wafer flipping assembly and the polishing head cleaning assembly share the operation channel to flip the wafer or clean the wafer polishing head;

[0005] The wafer flip assembly is arranged at the periphery of the wafer placement rack, and the wafer flip assembly includes a lifting mechanism and a wafer clamping mechanism installed on the lifting mechanism, the lifting mechanism is used to lift the wafer clamping mechanism, the wafer clamping mechanism can enter the operation channel radially to clamp the wafer when aligned with the wafer placement rack, and rotate to flip the wafer after the lifting mechanism lifts the wafer clamping mechanism; and

[0006] The polishing head cleaning assembly can pass through the operation channel along the axial direction to clean the wafer polishing head.

[0007] In the loading cup as described above, optionally, the wafer placement rack includes four arc-shaped components arranged along the circumferential direction, the arc-shaped components are used to support the wafer, and the operation channel is formed between adjacent arc-shaped components.

[0008] In the loading cup as described above, optionally, a wafer rack lifting sleeve is provided at the center of the wafer rack, the rack lifting sleeve is used to lift the arc-shaped component, and the top of the rack lifting sleeve is lower than the bottom of the arc-shaped component.

[0009] In the loading cup as described above, optionally, the wafer placement rack also includes an inner support frame extending radially for connecting the arc-shaped component and the placement rack lifting sleeve, the top of the placement rack lifting sleeve is provided with circumferentially distributed lugs, and grooves are formed between adjacent lugs, the radial outer end of the inner support frame is connected to the arc-shaped component, and the radial inner end of the inner support frame extends to the top of the placement rack lifting sleeve and is connected to the lugs.

[0010] In the loading cup as described above, optionally, the lifting mechanism has at least two lifting positions, a low position and a high position. The lifting mechanism is at a low position when the loading cup places a wafer, clamps a wafer, and cleans a wafer polishing head, and is at a high position when the loading cup flips a wafer.

[0011] In the loading cup as described above, optionally, the wafer clamping mechanism has a clamping head that can be extended and retracted along the radial direction of the wafer placement rack, and the clamping head has a clamping position and a release position. The clamping head is located at the release position when the loading cup places the wafer and cleans the wafer polishing head, and is located at the clamping position when the loading cup clamps the wafer and flips the wafer;

[0012] The wafer clamping mechanism is rotatably connected to the lifting mechanism, and the wafer clamping mechanism can rotate relative to the lifting mechanism to flip the wafer.

[0013] In the loading cup as described above, optionally, the polishing head cleaning assembly includes an air film cleaning brush and a retaining ring cleaning brush.

[0014] In the loading cup as described above, optionally, the air film cleaning brush extends radially along the wafer placement rack, the radial length of the air film cleaning brush is not less than the radius of the wafer, and the top surface of the air film cleaning brush has bristles.

[0015] In the loading cup as described above, optionally, a cleaning brush lifting device is provided at the center of the wafer placement rack, and the cleaning brush lifting device is used to lift the air film cleaning brush, and the air film cleaning brush has at least two lifting positions, a low position and a high position. The air film cleaning brush is located at a low position when the loading cup places the wafer, and is located at a high position when the loading cup clamps the wafer and cleans the wafer polishing head. The top of the air film cleaning brush at the high position is aligned with the top of the retaining ring cleaning brush.

[0016] In the loading cup as described above, optionally, the polishing head cleaning assembly includes two retaining ring cleaning brushes, and the retaining ring cleaning brushes are radially disposed on both sides of the wafer placement rack.

[0017] In the loading cup as described above, optionally, the retaining ring cleaning brush is slidably connected to the top of the carrier platform fixedly arranged on the radial outer side of the loading cup, and the retaining ring cleaning brush can reciprocate slightly in the radial direction or tangential direction.

[0018] In the loading cup as described above, optionally, the two wafer flipping assemblies are radially disposed on both sides of the loading cup, and the two wafer flipping assemblies act synchronously to clamp and flip the wafer.

[0019] In the loading cup as described above, optionally, the wafer placement rack, the wafer flip assembly and the polishing head cleaning assembly are installed on the same base, the base is cup-shaped, and the side wall of the base surrounds the outer circumference of the loading cup.

[0020] In the loading cup as described above, optionally, the air film cleaning brush also has a middle lifting position between the low position and the high position. When the wafer is broken, the air film cleaning brush located in the middle position is used to form an operating space between it and the base for cleaning wafer fragments.

[0021] In the loading cup as described above, optionally, a placement rack lifting device is provided at the center of the wafer placement rack, and the placement rack lifting device is used to lift the wafer placement rack, and the wafer placement rack has three lifting positions: low position, middle position, and high position;

[0022] The wafer placement rack is located in a low position when the loading cup cleans the wafer polishing head;

[0023] The wafer placement rack is located in a middle position when the wafer is placed in the loading cup, and the wafer placement rack located in the middle position is used to make the bottom of the wafer placed thereon higher than the top of the polishing head cleaning assembly;

[0024] The wafer placement rack is located at a high position when the loading cup clamps the wafer, and the wafer placement rack located at a high position is aligned with the wafer clamping mechanism.

[0025] In order to achieve the aforementioned object, a second aspect of the present invention provides a loading cup, wherein the loading cup comprises a wafer placement rack capable of adjusting the height, a wafer flipping assembly and a polishing head cleaning assembly;

[0026] The wafer placement rack has at least three lifting positions, namely, low position, middle position and high position; the wafer flip assembly has at least two lifting positions, namely, low position and high position; and the polishing head cleaning assembly has at least two lifting positions, namely, low position and high position;

[0027] When the wafer placement rack places the wafer, the wafer placement rack is in a middle position, the wafer flipping assembly is in a low position, and the polishing head cleaning assembly is in a low position;

[0028] When the wafer flipping assembly flips the wafer, the wafer placement rack, the wafer flipping assembly and the polishing head cleaning assembly are all in a high position;

[0029] When the polishing head cleaning assembly cleans the wafer, the wafer placement rack and the wafer flip assembly are in a low position, and the polishing head cleaning assembly is in a high position.

[0030] In the loading cup as described above, the wafer placement rack provides an operation channel, and the wafer flipping assembly and the polishing head cleaning assembly share the operation channel to flip the wafer or clean the wafer polishing head;

[0031] The wafer flip assembly is arranged on the outer periphery of the wafer placement rack, and the wafer flip assembly includes a wafer clamping mechanism, and the wafer clamping mechanism can enter the operation channel radially to clamp the wafer when the wafer placement rack is in a high position;

[0032] The polishing head cleaning assembly can axially pass through the operating channel to be in a low position when the wafer placement rack is in a middle position, and axially pass through the operating channel to be in a high position to clean the wafer polishing head when the wafer placement rack is in a low position.

[0033] In order to achieve the aforementioned object, a third aspect of the present invention provides a wafer polishing device, wherein the polishing device comprises a polishing unit base lifting assembly and a loading cup as described in any one of the aforementioned first and second aspects;

[0034] The polishing unit includes a polishing turntable, a wafer polishing head, a polishing head moving assembly, a polishing liquid supply assembly and a trimming assembly, and the bearing cup is connected to a base lifting assembly;

[0035] The wafer polishing head is used for polishing the wafer on the polishing turntable, and can absorb and move the wafer;

[0036] The polishing head moving assembly moves the wafer between the loading cup and the polishing turntable by moving the wafer polishing head, and is used to move the wafer polishing head above the loading cup and use the loading cup to clean the wafer polishing head;

[0037] The base lifting assembly lifts the loading cup by lifting the base of the loading cup. The base has two lifting positions, low and high. The base is at the low position when the loading cup clamps the wafer and flips the wafer, and is at the high position when the loading cup places the wafer and cleans the wafer polishing head.

[0038] In order to achieve the aforementioned objective, a fourth aspect of the present invention provides a wafer processing device, wherein the wafer processing device performs chemical mechanical polishing using the wafer polishing apparatus as described in the third aspect.

[0039] In order to achieve the aforementioned object, a fifth aspect of the present invention provides a method for using the loading cup as described in any one of the first and second aspects, wherein the method comprises:

[0040] Placing the wafer, when placing the wafer, controlling the lifting and lowering of the wafer placement rack and the polishing head cleaning assembly so that the bottom of the wafer placed on the wafer placement rack is higher than the top of the polishing head cleaning assembly;

[0041] Flip the wafer. The steps of flipping the wafer include:

[0042] Flipping step I, clamping the wafer, first, controlling the lifting and lowering of the lifting mechanism and the wafer placement rack, so that the wafer clamping mechanism installed on the lifting mechanism is aligned with the wafer placement rack, and then controlling the wafer clamping mechanism to enter the operating channel of the wafer placement rack in the radial direction to clamp the wafer placed on the wafer placement rack;

[0043] Flipping step II, flipping the wafer, first, controlling the lifting mechanism to lift the wafer clamping mechanism and the wafer to the highest position, then rotating the wafer clamping mechanism 180 degrees to flip the wafer;

[0044] Flipping step III, putting the wafer back, first, controlling the lifting mechanism to lower the wafer clamping mechanism and the wafer until the wafer clamping mechanism is aligned with the wafer placement rack, then controlling the wafer clamping mechanism to move radially outward from the operation channel, so as to place the flipped wafer back on the wafer placement rack;

[0045] Cleaning the wafer polishing head. The steps of cleaning the wafer polishing head include:

[0046] Cleaning step I: raising the polishing head cleaning assembly and passing it through the operating channel axially until its top end is higher than the wafer placement rack.

[0047] Cleaning step II, moving the wafer polishing head to fit the polishing head cleaning assembly, rotating the wafer polishing head to start cleaning.

[0048] The loading cup of the present invention comprises a wafer placing rack, a wafer turning assembly and a polishing head cleaning assembly. The device can be used to more conveniently clean the wafer polishing head, thereby reducing crystallization on the polishing head and improving the wafer polishing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The disclosure of the present invention will become more apparent with reference to the accompanying drawings. It should be understood that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings:

[0050] Figure 1A schematic perspective view of an embodiment of a loading cup according to the present invention;

[0051] Figure 2 for Figure 1 A schematic three-dimensional diagram of an embodiment of the present invention when placing a wafer;

[0052] Figure 3 for Figure 2 A longitudinal cross-sectional view of the embodiment along the AA section line;

[0053] Figure 4 for Figure 1 A schematic three-dimensional diagram of an embodiment of the present invention when clamping a wafer;

[0054] Figure 5 for Figure 4 A longitudinal cross-sectional view of the embodiment along the BB section line;

[0055] Figure 6 for Figure 1 A schematic three-dimensional diagram of an embodiment of the present invention when a wafer is flipped;

[0056] Figure 7 for Figure 1 A schematic three-dimensional diagram of an embodiment of the present invention when cleaning a wafer polishing head;

[0057] Figure 8 for Figure 7 A longitudinal cross-sectional view of the embodiment along the DD section line;

[0058] Fig. 9 for Figure 7 A longitudinal cross-sectional view of the embodiment along the CC section line;

[0059] Fig.10 A flow chart of flipping a wafer in a method of using a loading cup of the present invention;

[0060] Fig.11 The present invention is a flow chart of cleaning a wafer polishing head in the method of using a loading cup.

[0061] Fig.12 It is a schematic diagram of an embodiment of a wafer polishing device of the present invention.

[0062] Figure markings: 1-wafer; 2-wafer polishing head; 3-air film; 4-retaining ring; 5-wafer placement rack; 6-operating channel; 7-arc-shaped component; 8-inner support frame; 9-placing rack lifting sleeve; 10-guide ramp; 11-wafer flipping assembly; 12-lifting mechanism; 13-wafer clamping mechanism; 14-clamping head; 15-clamping groove; 16-polishing head cleaning assembly; 17-first flipping mechanism; 18-second flipping mechanism; 19-air film cleaning brush; 20-retaining ring cleaning brush; 21-top plane; 22-slide rail; 23-carrying platform; 24-cleaning brush lifting sleeve; 25-base; 26-base side wall; 27-sliding column; 29-limiting column; 31-groove; 32-support frame unit; 33-rotating axis. DETAILED DESCRIPTION

[0063] With reference to the accompanying drawings and specific embodiments, the structure, composition, characteristics and advantages of a loading cup and a method of using the same, a wafer polishing device and a processing equipment of the present invention will be described below in an exemplary manner. However, all descriptions should not be used to form any limitations on the present invention.

[0064] For any single technical feature described or implied in the embodiments mentioned in this document, or any single technical feature displayed or implied in the accompanying drawings, the present invention still allows any combination or deletion between these technical features (or their equivalents) without any technical obstacles, and thus it should be considered that these more embodiments according to the present invention are also within the scope of the description of this document.

[0065] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features.

[0066] In the description of the present application, it should be understood that the terms "upper", "lower", "left", "right", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0067] Figure 1 FIG. 1 is a schematic perspective view of an embodiment of a loading cup according to the present invention.

[0068] The loading cup includes a wafer placement rack 5, a wafer flip assembly 11, and a polishing head cleaning assembly 16. Figure 1 Not shown, see Figure 2) during the CMP process, the white edge area can be significantly reduced by using double-sided polishing. Currently, double-sided polishing can only be achieved by manually placing and taking the wafer and performing a flipping operation. However, manual placement of the wafer is inefficient and has certain risks. The loading cup of the present invention can be installed next to the CMP equipment, or as a component of the CMP equipment, to conveniently flip the wafer 1. After the wafer 1 completes the CMP processing on the first side, it is transported to the loading cup of the present invention, flipped by the wafer flipping assembly 11, and then transported back to the CMP processing position for processing on the other side.

[0069] like Figure 1 As shown, the horizontal cross section of the wafer is usually circular, and the supporting cup used to place the wafer horizontally usually has a shape consistent with the wafer. Therefore, the axial direction is used below to represent the direction perpendicular to the horizontal cross section of the wafer, that is, the height direction or the vertical direction; the radial direction is used to represent the wafer diameter direction, that is, the direction passing through the center in the horizontal direction; the axial direction is used to represent the wafer circumferential direction, that is, the direction around the center in the horizontal direction. Even if the horizontal cross section of the wafer is not circular, those skilled in the art should be able to understand the meaning of the above directions.

[0070] In this process, the wafer placement rack 5 is used to place the wafer 1. The wafer placement rack 5 can be provided with a receiving portion that matches the side shape of the wafer 1, and receives the wafer by contacting the side of the wafer 1, so as to avoid leaving marks due to contacting the bottom or top surface of the wafer, thereby affecting the surface quality. To this end, the side of the wafer 1 can be designed as a conical surface or a step surface, or can be designed to have a radial protrusion, or other side shapes that are easy to receive.

[0071] The wafer placement rack 5 can adjust the height, and the wafer placement rack 5 provides an operation channel 6. The wafer flip assembly 11 and the polishing head cleaning assembly 16 can move, and the operation channel 6 provides a moving channel for the assembly 11 and the assembly 16 to avoid interference with the wafer placement rack 5. When no action is performed, the loading cup is in a default state, and the loading cup in this state is in a sleep mode, which can reduce the power consumption of the loading cup. The loading cup can be adjusted to a default state after executing the instructions of placing a wafer, flipping a wafer or cleaning a wafer polishing head, and this state can be used as the starting position before executing the next instruction. The default state is fixed, and any of the above instructions executed from this state only need to use the preset fixed action parameters, without recalculating the action parameters according to the state after the last instruction is executed. Therefore, the design of the default state makes the control of the loading cup more convenient. The wafer flip assembly 11 is arranged on the periphery of the wafer placement rack 5. Since the wafer 1 is placed on the inner side of the wafer placement rack 5, the wafer flip assembly 11 can be arranged on the outer side of the wafer placement rack 5, so as to clamp the wafer 1 inward. A plurality of wafer flipping assemblies 11 can clamp the wafer 1 from the side in multiple directions, or a single wafer flipping assembly 11 can clamp the wafer 1 from the top (e.g., suction cup adsorption). After clamping the wafer 1, the wafer flipping assembly 11 turns the wafer 1 over. After the wafer is turned over, the wafer 1 can be taken away directly and other processes can be continued, or the wafer flipping assembly 11 can be put back into the wafer placement rack 5 before being taken away. Therefore, the wafer flipping assembly 11 includes a lifting mechanism 12 and a wafer clamping mechanism 13 installed on the lifting mechanism 12. Among them, the wafer clamping mechanism 13 is used to clamp and flip the wafer 1. When the wafer clamping mechanism 13 is aligned with the wafer placement rack 5, it can radially enter the operating channel 6 to clamp the wafer 1 and rotate to flip the wafer 1 after the lifting mechanism 12 lifts the wafer clamping mechanism 13. The wafer clamping mechanism 13 can also be driven to flip the wafer 1 during the process of the lifting mechanism 12 lifting the wafer 1. At this time, the speed at which the lifting mechanism 12 lifts the wafer 1 and the wafer clamping mechanism 13 flips the wafer 1 so that the edge of the wafer 1 will not touch the wafer placement rack 5, thereby saving the time required to flip the wafer.

[0072] In the CMP process, the wafer polishing head 2 (such as Figure 8 As shown in FIG. 1 , the wafer 1 is carried to rotate on the polishing pad on the surface of the polishing turntable, and the downward surface of the wafer 1 is polished with a polishing liquid. In this process, the polishing liquid splashes onto the wafer polishing head 2 and forms a film 3 (as shown in FIG. 1 ). Figure 8 As shown) of the outer ring and edge, and retaining ring 4 (as shown) Figure 8Crystals are formed on the wafer 1, which will affect the maintenance of the wafer polishing head 2 and the cleaning effect of the wafer 1 after CMP. Therefore, the loading cup of the present invention includes a polishing head cleaning assembly 16, which is specifically used to clean the wafer polishing head 2, and the polishing head cleaning assembly 16 can pass through the operating channel 6 axially to clean the wafer polishing head 2. Since the diameter of the wafer polishing head 2 is larger than that of the wafer 1, in order to clean the wafer polishing head 2, the radial dimension of the polishing head cleaning assembly 16 should be greater than or equal to that of the wafer 1. The operating channel 6 of the wafer placement rack 5 provides a channel for the polishing head cleaning assembly 16, so that the polishing head cleaning assembly 16 can pass through the wafer placement rack 5 longitudinally during the ascent or descent process without interference. The design of the operating channel 6 makes the loading cup more compact in radial direction, thereby improving the space utilization of the device. In other words, by making the wafer flipping assembly 11 and the polishing head cleaning assembly 16 share the operating channel 6 to flip the wafer or clean the wafer polishing head, the wafer flipping assembly 11 and the polishing head cleaning assembly 16 can be accommodated simultaneously in the limited space inside the supporting cup and between the supporting cup and the wafer polishing head 2 without setting up additional wafer flipping equipment or wafer cleaning equipment, thereby reducing costs and improving the efficiency of the overall process flow.

[0073] As an optional embodiment, a guiding slope 10 can be provided on the inner side of the wafer placement rack 5, and the top of the guiding slope 10 is connected to the top plane 21 of the wafer placement rack 5, which is usually used to receive the bottom of the wafer. The guiding slope 10 extends radially inward and tilts downward, thereby reducing the contact area between the top plane 21 and the wafer to avoid contamination of the wafer. Figure 3 ) can form a side of a specific shape, so that the wafer is less susceptible to damage in subsequent processing. The side can be a convex arc, a convex V-face or a conical surface. The guiding bevel 10 can also be used to place the wafer, so its shape should also adapt to the shape of the wafer side. For example, the wafer side and the guiding bevel can be conical surfaces with the same diameter and taper. In the process of wafer 1 being placed on the wafer placement rack 5, the guiding bevel 10 can guide the falling direction of wafer 1 and play a role in positioning the wafer.

[0074] The wafer placement rack 5 may include four arc-shaped parts 7, which are used to support the wafer and are arranged circumferentially on the wafer placement rack 5. The arc-shaped parts 7 are arc-shaped with a relatively narrow width, and an operating channel 6 can be formed between the arc-shaped parts 7, thereby improving the space utilization of the wafer placement rack 5 and the wafer flip assembly 11 and the polishing head cleaning assembly 16, making the loading cup structure more compact and reducing the occupied space. Further, the inner diameters of the four arc-shaped parts 7 can be the same, and can be symmetrically distributed on the same horizontal plane, so that the force of the wafer placement rack 5 when carrying the wafer 1 is more balanced, and the structural stability is improved. At the same time, this arrangement also makes the operating channel 6 symmetrical, and the two operating channels 6 are opposite to each other along the radial direction of the wafer placement rack 5. It is convenient to arrange the wafer flip assembly 11 and the polishing head cleaning assembly 16 in the two channels, which will make their arrangement symmetrical. The symmetrical arrangement of the wafer placement rack 5, the wafer flip assembly 11 and the polishing head cleaning assembly 16 can ensure that the entire loading cup is more balanced during operation, reducing vibration or offset that may be caused by the asymmetrical layout; secondly, the symmetrical design helps to evenly distribute the workload of each component, avoid excessive force on one side, and extend the service life of the equipment. In addition, the wafer flip assembly 11 in the radially opposed operating channel 6 can clamp the wafer along the diameter of the wafer 1, improving the accuracy and stability of the wafer 1 clamping; and the polishing head cleaning assembly 16 in the radially opposed operating channel 6 can clean the wafer polishing head 2 along the diameter of the wafer polishing head 2, improving the efficiency and stability of cleaning.

[0075] Optionally, the top of the wafer placement rack 5 may be provided with no less than three limiting posts 29 along the circumferential direction. Specifically, the top of the arc-shaped component 7 of the wafer placement rack 5 may have a coplanar top plane 21, and the limiting posts are dispersedly arranged on the outer edge of the top plane of the arc-shaped component. The top of the limiting post may be provided with an upwardly protruding arc surface to guide the descending wafer 1 so that the wafer 1 accurately falls on the part of the top plane inside the limiting post. The top plane 21 may be an arc with a width greater than the diameter of the limiting post. The width of this part of the top plane is relatively small, so the contact area with the wafer is small, which can better avoid contaminating the wafer surface. At the same time, the limiting post can limit the radial movement of the wafer and enhance the stability of the wafer during movement.

[0076] As an optional embodiment, a placement rack lifting sleeve 9 can be provided at the center of the wafer placement rack 5, and the placement rack lifting sleeve is used to lift the arc-shaped component 7, thereby lifting the wafer. The top of the placement rack lifting sleeve 9 can be lower than the bottom of the arc-shaped component 7, so that the placement rack lifting sleeve 9 avoids interference with the bottom of the wafer. At the same time, setting the placement rack lifting sleeve 9 at a relatively low position can further avoid interference between the top of the placement rack lifting sleeve 9 and the bottom of the air film cleaning brush, thereby providing a larger activity space for the air film cleaning brush in the vertical direction.

[0077] Optionally, the wafer placement rack may further include an inner support frame 8 extending radially. The inner support frame 8 is used to connect the arc-shaped component 7 and the placement rack lifting sleeve 9. Four arc-shaped components 7 may be connected to the radial outer end of the inner support frame 8, and the top of the placement rack lifting sleeve 9 may be provided with circumferentially distributed lugs, the number of which may be four corresponding to the arc-shaped components, and the setting orientation may be respectively opposite to the four arc-shaped components. Compared with the disc-type wafer placement rack 5, this design can reduce the weight of the wafer placement rack 5, and leave space to accommodate the air film cleaning brush 19, thereby improving the space utilization rate. The radial inner end of the inner support frame may extend radially inward to the top of the placement rack lifting sleeve, and the radial inner end is higher than the top of the placement rack lifting sleeve. The top of the placement rack lifting sleeve may be provided with circumferentially distributed lugs, and a groove 31 may be formed between adjacent lugs, the groove extending axially, and its opening facing upward. The groove may be provided for the air film cleaning brush to slide in from the opening above along the axial direction, so the width of the groove 31 may be greater than the width of the air film cleaning brush 19. The radial inner end of the inner support frame can be connected to the top of the lug of the placement frame lifting sleeve, so that the groove depth and the sliding distance of the air film cleaning brush in the groove are maximized. When placing and clamping wafers, the top of the air film cleaning brush and its bristles should be lower than the bottom of the wafer to prevent the residual liquid on the bristles from contaminating the wafer surface. Therefore, the air film cleaning brush should be moved to a position lower than the wafer placement frame. For example, this position can make the top of the bristles of the air film cleaning brush lower than the plane where the bottom of the arc bracket is located, so as to avoid the purpose of the wafer. At this time, the groove provides a channel for the air film cleaning brush to slide in along the axial direction, thereby reducing the required height of the wafer placement frame 5 and making the structure of the device more compact. In this embodiment, when the bottom of the air film cleaning brush 19 abuts against the bottom of the groove, the top of the bristles of the air film cleaning brush 10 is set to be flush with the plane where the bottom of the arc bracket is located, so that the overall height of the loading cup remains basically unchanged.

[0078] As an optional embodiment, the inner support frame 8 may include four support frame monomers 32, the inner side of each arc-shaped component 7 is respectively connected to a support frame monomer 32, and each support frame monomer 32 is a single-strand three-pronged structure, the single-strand three-pronged structure includes a radially extending main part, two fork parts are separated from the end of the main part, and the main part and the fork part are connected to the inner side of the arc-shaped component 7 at three connection points. The support frame monomer 32 with a single-strand three-pronged structure has good torsion resistance and light weight, which is conducive to improving the rigidity of the wafer placement rack 5 and making the wafer 1 more stably placed on the wafer placement rack. Figure 1 It can be seen that the support frame unit 32 composed of the main part and the two fork parts leaves a large space in the middle of the wafer placement frame 5, which is convenient for other components of the loading cup to move therein. In addition, the inner support frame can also be designed into a variety of structures, the number of forks can also be other numbers, and the connection parts with the arc-shaped component 7 can also be located in different planes.

[0079] Optionally, the lifting mechanism 12 has at least two lifting positions, a low position and a high position, and the lifting mechanism 12 can drive the wafer clamping mechanism 13 to move between the low position and the high position. The lifting mechanism is in a low position when the loading cup places the wafer, clamps the wafer, cleans the wafer polishing head, and is in a default state, and is in a high position when the loading cup flips the wafer. Since the wafer clamping mechanism 13 is installed on the lifting mechanism, when the lifting mechanism moves between the low position and the high position, the height of the wafer clamping mechanism will change synchronously. The lifting mechanism 12 can realize the lifting function by using an electric push rod to drive a telescopic sleeve with three sleeves: when the electric push rod is not extended, the first, second and third sleeves are in a low position and nested from the inside to the outside, and the lifting mechanism is in a low position; the electric push rod is extended, and the first, second and third sleeves are extended in sequence until the electric push rod is extended to the longest, and the first, second and third sleeves are in sequence from high to low, and the lifting mechanism is in a high position. The use of a lifting mechanism 12 with two-stage lifting positions to change the height of the wafer clamping mechanism provides sufficient operating space for flipping the wafer, so that the wafer does not collide with the wafer placement rack and the polishing head cleaning component during the flipping process, thereby ensuring the wafer yield. In addition, setting a two-stage lifting height simplifies the height measurement equipment of the lifting mechanism, and there is no need to use a high-energy-consuming and heavy active distance measuring device. A passive magnetic induction switch or a mechanically triggered limit switch can be used to accurately detect whether the lifting mechanism has reached a low position or a high position. Therefore, the lifting mechanism has a simple structure and high reliability. In addition, the lifting mechanism 12 can have lifting positions other than the low position and the high position. Any technical solution that uses a lifting mechanism with a low position and a high position to flip the wafer should fall within the protection scope of the present invention.

[0080] Specifically, the lifting height of the lifting mechanism 12 for performing the wafer flipping action can vary according to the size of the flipped wafer, and the larger the wafer size, the greater the height. In this embodiment, the maximum lifting height of the lifting mechanism 12 can flip a 12-inch wafer.

[0081] Optionally, the wafer clamping mechanism 13 also performs corresponding actions during wafer placement, wafer clamping and wafer flipping. At a corresponding height, the wafer clamping mechanism 13 can be extended and retracted in the horizontal direction, and the wafer clamping mechanism 13 is rotatably connected to the lifting mechanism 12. Among them, the wafer clamping mechanism 13 includes a clamping head 14 that can be extended and retracted in the radial direction of the wafer placement rack. When the wafer placement rack and the wafer thereon are placed horizontally, the clamping head is extended and retracted in the horizontal direction. The clamping head has a clamping position and a release position. "Clamping position" and "release position" are descriptions of the position of the clamping head relative to the wafer placement rack. Specifically, the release position is that the clamping head is farther away from the center of the wafer placement rack in the radial direction, and the clamping position is that the clamping head is closer to the center of the wafer placement rack in the radial direction. The clamping head is located in the release position when the loading cup places the wafer, cleans the wafer polishing head and is in the default state, and is located in the clamping position when the loading cup clamps the wafer and flips the wafer. The clamping head is used to pass through the operating channel radially when clamping the wafer, clamp the edge of the wafer placed on the wafer placement rack, and when flipping the wafer, the clamping head of the wafer clamping mechanism remains in the clamping position to clamp the wafer, and the wafer clamping mechanism rotates relative to the lifting mechanism to flip the wafer. The clamping head 14 can be connected to the wafer clamping mechanism 13 through an electric push rod, a cylinder or a motor-driven screw module (not shown in the accompanying drawings), so as to achieve telescopic movement relative to the wafer clamping mechanism 13. The wafer clamping mechanism 13 can be connected to the lifting mechanism 12 through a rotating shaft 33, and the rotating shaft 33 can be coaxially connected to a stepper motor or a servo motor (not shown in the accompanying drawings) fixedly mounted on the lifting mechanism 12, and the motor drives the rotating shaft 33 to rotate, thereby driving the rotation of the wafer clamping mechanism 13. The telescopic design of the wafer clamping mechanism 13 enables it to adjust its position at different heights, ensuring that the clamping head 14 can first accurately align the wafer 1 in the horizontal direction, and then clamp the wafer, thereby improving the accuracy of clamping the wafer. By driving the rotating shaft 33 with a stepper motor or a servo motor, the rotation angle of the wafer clamping mechanism 13 and the wafer 1 can be accurately controlled to ensure the rotation accuracy of the wafer 1 .

[0082] Optionally, a clamping groove 15 (such as Figure 3 As shown), the clamping groove 15 is adapted to the side shape of the wafer 1, so the clamping groove 15 can have a certain curvature, and the radius of the curvature needs to be adapted to the radius of the wafer. In this embodiment, the clamping groove 15 has a convex and symmetrical top and bottom and a concave middle. When the side of the wafer 1 is conical, the clamping groove can stably clamp the edge of the wafer regardless of whether the wafer is on the front or back. The clamping head 4 can clamp the side of the wafer 1 through the side of the clamping groove 15, providing sufficient friction to stabilize the wafer 1 and prevent it from falling during the flipping process. In this case, the side of the clamping groove 15 can be attached with elastic material to prevent the wafer 1 from breaking due to excessive clamping force.

[0083] The clamping head can be moved between the clamping position and the release position by the following implementation: the clamping head can be connected to the wafer clamping mechanism 13 through a horizontal movable sleeve rod, and a cylinder is arranged on the wafer clamping mechanism 13. The cylinder pushes the connecting rod arranged inside the wafer clamping mechanism 13 and converts the vertical thrust into the horizontal thrust through the gear structure or the inclined structure, thereby pushing the movable sleeve rod to extend and retract. This design makes full use of the internal space of the wafer clamping mechanism 13, and the main driving device that drives the clamping head to extend and retract is installed on the wafer clamping mechanism 13, so as to reduce the volume and weight of the clamping head and improve the stability of wafer clamping.

[0084] Optionally, the polishing head cleaning assembly 16 includes an air film cleaning brush 19 and a retaining ring cleaning brush 20. The air film 3 is located at the center of the wafer polishing head 2, and the retaining ring 4 surrounds the outside of the air film. The retaining ring cleaning brush is arranged on the radial outside of the air film cleaning brush, and the two can be arranged at different positions in the circumference, so that the radial positions of the retaining ring and the retaining ring cleaning brush match. When cleaning the wafer polishing head, the wafer polishing head can be moved to align with the polishing head cleaning assembly of the loading cup in the vertical direction, that is, the center of the air film, the center of the retaining ring and the center of the air film cleaning brush are located on the same vertical axis, and the bottom surface of the retaining ring and the retaining ring cleaning brush are aligned in the vertical direction. Since the air film 3 and the retaining ring 4 are made of different materials, the applicable cleaning brush materials are also different. The air film cleaning brush 19 can use relatively short bristles made of resin material. The retaining ring cleaning brush 20 can use a relatively long brush, and brushes of different materials can achieve higher cleaning efficiency for the air film 3 and the retaining ring 4 respectively. When cleaning the polishing head, the wafer polishing head 2 rotates itself, so that the air film and the retaining ring move in a circular motion relative to the air film cleaning brush 19 and the retaining ring cleaning brush 20 to achieve a cleaning effect. The cleaning brush can be designed in various shapes to improve the cleaning efficiency by increasing the contact area with the air film or the retaining ring.

[0085] Optionally, the air film cleaning brush 19 can be designed to remain radially stationary. The air film cleaning brush 19 can be in the shape of an elongated strip and extend radially along the wafer placement rack 5. The length of the air film cleaning brush 19 can be greater than the diameter of the air film 3, so that the cleaning range of the air film cleaning brush 19 includes the entire air film 3 and a portion of the bottom of the retaining ring close to the radial inner side. After the retaining ring cleaning brush has cleaned the retaining ring, contaminants may still be attached to it. The air film cleaning brush can further clean the retaining ring. The two cleaning brushes act together on the retaining ring to improve the cleaning effect. The length of the air film cleaning brush 19 can also be designed to be smaller than the diameter of the air film 3 and larger than the radius of the air film 3. The air film cleaning brush needs to be installed eccentrically. When cleaning the wafer polishing head, through the rotation of the polishing head, the cleaning range of the air film cleaning brush 19 can also cover the bottom surface of the air film 3. The cleaning efficiency is relatively low, and the advantage is that it takes up less space. Bristles can be set on the top of the air film cleaning brush 19, and the bristles can be made of PVC material. PVC material has strong corrosion resistance and can resist damage to the air film cleaning brush 19 by polishing liquid or chemical cleaning agents used in the cleaning process, thereby extending the service life. Moreover, PVC material is soft and can protect the surface of the air film 3 while effectively cleaning.

[0086] Optionally, the polishing head cleaning assembly 16 includes two retaining ring cleaning brushes 20, which are radially disposed on both sides of the wafer placement rack 5. The use of two retaining ring cleaning brushes 20 increases the contact area with the retaining ring and improves the cleaning efficiency. At the same time, the radially opposed retaining ring cleaning brushes 20 are conducive to ensuring that the retaining ring 4 is evenly stressed during the cleaning process, thereby ensuring the stability of the rotating wafer polishing head.

[0087] Figure 2 for Figure 1 A schematic three-dimensional diagram of an embodiment of the present invention when placing a wafer; Figure 3 for Figure 2 A longitudinal cross-sectional view of the embodiment along the AA section line. Figure 3 The up-down direction in the figure is parallel to the axial direction of the loading cup, and the left-right direction in the figure is parallel to the radial direction of the loading cup.

[0088] Optionally, a cleaning brush lifting device is provided at the center of the wafer placement rack 5 (not provided at Figure 3 ), the cleaning brush lifting device is used to lift the air film cleaning brush 19, the air film cleaning brush 19 has at least two lifting positions, low and high. The air film cleaning brush is located in the low position when the loading cup is placed on the wafer and in the default state. In this loading cup, the wafer 1 and the cleaning wafer polishing head 2 (see Figure 8) is in a high position, and the top of the air film cleaning brush in the high position is aligned with the top of the retaining ring cleaning brush. The cleaning brush lifting device can adopt a cylinder, and the fixed end of the cylinder is vertically installed on the loading cup, and the piston end of the cylinder is fixedly connected to the air film cleaning brush 19, thereby driving the air film cleaning brush 19 to rise and fall. When the loading cup places the wafer, the air film cleaning brush 19 is lowered to a low position. The air film cleaning brush carries residual cleaning liquid. When placing the wafer, in order to avoid the cleaning liquid on the air film cleaning brush contaminating the wafer, the air film cleaning brush can be driven to a low position and the wafer placement rack to a middle position, so that the top of the air film cleaning brush is lower than the bottom surface of the wafer. When flipping the wafer, the air film cleaning brush and the wafer placement rack can also be lowered to a low position, which can provide more space for wafer flipping, reduce the required height of wafer lifting, and reduce the volume of the lifting mechanism 12. When the polishing head needs to be cleaned, the air film cleaning brush 19 is adjusted to a high position so that its top is higher than the top of the wafer placement rack 5 and aligned with the top of the retaining ring cleaning brush, so that the polishing head cleaning assembly (see Figure 1 ) is in full contact with the polishing head. The two-stage lifting design of the air film cleaning brush makes full use of the space above and below the wafer placement rack 5, making the loading cup structure more compact and smaller in size. In this embodiment, when the air film cleaning brush and the wafer placement rack are both in a high position or in a low position, the bottom of the air film cleaning brush 19 abuts against the bottom of the groove, so that the strokes of each meet the functional requirements while the overall height of the loading cup remains basically unchanged.

[0089] In addition, the air film cleaning brush can also have a middle lifting position between the low position and the high position. When the loading cup is used, the wafer may be broken and the wafer fragments dropped into the device need to be cleaned. At this time, the air film cleaning brush is adjusted to the middle position to form an operating space for cleaning the wafer fragments between the air film cleaning brush and the base of the device. The middle position of the air film cleaning brush is not used when the loading cup is in the default state, placing the wafer, flipping the wafer, clamping the wafer or cleaning the wafer polishing head.

[0090] Figure 4 for Figure 1 A schematic three-dimensional diagram of an embodiment of the present invention when clamping a wafer; Figure 5 for Figure 4 A longitudinal cross-sectional view of the embodiment along the BB section line; Figure 6 for Figure 1 A schematic three-dimensional diagram of an embodiment of the present invention when a wafer is flipped.

[0091] Optionally, two wafer flipping assemblies 11 (see Figure 1) can be radially disposed on both sides of the loading cup, which are the first flipping mechanism 17 and the second flipping mechanism 18. The first flipping mechanism 17 and the second flipping mechanism 18 can act synchronously and cooperate with each other to complete the clamping and flipping of the wafer 1. The wafer clamping mechanism 13 of the first flipping mechanism 17 and the second flipping mechanism 18 can enter the operating channel 6 radially and clamp the wafer 1 from both sides of the wafer 1. The lifting mechanism 12 of the first flipping mechanism 17 and the second flipping mechanism 18 can be lifted and lowered synchronously to keep the wafer horizontal during the lifting process. The first flipping mechanism 17 and the second flipping mechanism 18 clamp the wafer symmetrically, so that the wafer 1 is subjected to a balanced clamping force, and the clamping state is more stable.

[0092] The first flip mechanism 17 and the second flip mechanism 18 each have a lifting mechanism 12 and a wafer clamping mechanism 13, and the wafer clamping mechanism 13 can rotate relative to the lifting mechanism 12, so as to realize the flipping of the wafer 1. That is, the wafer clamping mechanism 13 of the first flip mechanism 17 and the second flip mechanism 18 can rotate relative to their respective lifting mechanisms 12. In this embodiment, the first flip mechanism 17 and the second flip mechanism 18 are radially opposed to each other to ensure that the rotation axis 33 they each have is coaxial, so that the first flip mechanism 17 and the second flip mechanism 18 can cooperate to flip the wafer 1. Further, the wafer clamping mechanism 13 of the first flip mechanism 17 and the second flip mechanism 18 can also be radially opposed to each other along the wafer placement rack 5, so that the clamping force of the two wafer clamping mechanisms 13 on the wafer 1 passes through the center of the wafer 1, so that the first flip mechanism 17 and the second flip mechanism 18 stably clamp the wafer 1.

[0093] Figure 7 for Figure 1 A schematic three-dimensional diagram of an embodiment of the present invention when cleaning a wafer polishing head; Figure 8 for Figure 7 A longitudinal cross-sectional view of the embodiment along the DD section line; Fig. 9 for Figure 7 A longitudinal cross-sectional view of the embodiment along the CC section line.

[0094] In this embodiment, the retaining ring cleaning brush 20 can be radially disposed on both sides of the wafer placement rack 5, and the radial directions of the retaining ring cleaning brushes 20 on the two sides are different from the radial directions of the first flip mechanism 17 and the second flip mechanism 18. The wafer placement rack 5 is also provided with an operating channel 6 at a position opposite to the retaining ring cleaning brush 20, and the retaining ring cleaning brush 20 can slide in the operating channel.

[0095] As an optional embodiment, the retaining ring cleaning brush 20 can be slidably connected to the top of the carrier platform fixedly arranged on the radial outer side of the loading cup, and the retaining ring cleaning brush 20 can reciprocate slightly in the radial direction or tangential direction. Specifically, the retaining ring cleaning brush 20 can be installed on the carrier platform 23 fixedly arranged on the loading cup through a slide rail 22 arranged in the radial direction or tangential direction, and the retaining ring cleaning brush 20 can slide along the slide rail 22. Figure 8 The slide rail 22 arranged in the radial direction is shown. In this embodiment, the slide rail 22 guides the retaining ring cleaning brush 20 to slide in the radial direction. The length of the retaining ring cleaning brush 20 can be greater than the width of the retaining ring, so that the retaining ring can be covered in the radial direction, and with its reciprocating sliding, it can brush the joint between the retaining ring and the air film, so as to clean the wafer polishing head more thoroughly. When placing the wafer, the wafer polishing head can be lowered to the retaining ring and the upper surface of the wafer placement rack 5 to abut against each other; and when cleaning the wafer polishing head, the wafer polishing head can be lowered to a certain distance between the retaining ring and the highest point of the upper surface of the wafer placement rack 5, for example, it is about to contact the top of the limiting column 29. In other words, the top of the limiting column 29 should be lower than the top of the air film cleaning brush and the retaining ring cleaning brush, so that the rotation of the wafer polishing head does not contact the part of the carrier cup except the polishing head cleaning assembly 16, and at the same time, the bottom of the retaining ring will apply a suitable downward pressure to the bristles of the retaining ring cleaning brush 20. Therefore, part of the bristles of the retaining ring cleaning brush 20 can enter the joint between the retaining ring and the air film. Regardless of whether the retaining ring cleaning brush moves radially or tangentially, the movement trajectory of its bristles does not coincide with the rotation direction of the polishing head. The bristles do not move along the seam, but will continuously enter and exit the seam, which is conducive to sweeping out the contaminants in the gap, thereby more fully cleaning the wafer polishing head. Since the width of the retaining ring is relatively small, the retaining ring cleaning brush adopts a small reciprocating motion and a relatively short stroke, which can apply a relatively large cleaning force to the cleaning brush to obtain a better cleaning effect.

[0096] The retaining ring cleaning brush 20 can be a brush, which has both elasticity and toughness, can fit the uneven changes in the surface texture of the retaining ring, improve the cleaning effect, and can also effectively clean the retaining ring and the joint between it and the air film. The retaining ring cleaning brush 20 can be driven by a reciprocating power device, including but not limited to a crank slider mechanism, a ball screw, etc., which can continuously and stably drive the retaining ring cleaning brush 20 to reciprocate to ensure the cleaning effect. In order to enhance the cleaning effect of the retaining ring, an eccentric shaft motor can be provided on the aforementioned reciprocating drive device. The eccentric shaft motor can be used to drive the retaining ring cleaning brush to reciprocate while causing it to vibrate at a relatively high frequency. The motion trajectory of the retaining ring cleaning brush will be more diverse and the cleaning effect will be stronger.

[0097] Optionally, the wafer placement rack 5 and the wafer flip assembly 11 (see Figure 1 ) and polishing head cleaning assembly 16 (see Figure 1) can be installed on the same base 25, the base 25 can be cup-shaped, and the side wall 26 of the base surrounds the outer periphery of the loading cup. The base side wall 26 is annular around the edge of the base 25, enclosing the wafer placement rack 5, the wafer flip assembly 11 and the polishing head cleaning assembly 16. The design of the base 25 enhances the structural stability and compactness of the loading cup. Since the positions of the wafer placement rack 5, the wafer flip assembly 11 and the polishing head cleaning assembly 16 need to cooperate with each other, the use of a fixed base 25 to install the above components is conducive to improving the assembly accuracy of the various components of the loading cup and improving reliability. In order to ensure the part accuracy and assembly accuracy of the loading cup, the above-mentioned base side wall 26 can also be designed to prevent accidental bumps on the wafer placement rack 5, the wafer flip assembly 11 and the polishing head cleaning assembly 16. In addition, since the loading cup includes movable components and drive devices such as the lifting mechanism 12 and the cleaning brush lifting device, as well as auxiliary moving parts such as the slide rail 22, the base side wall 26 can prevent external liquid from splashing onto the wafer to cause contamination, and can also be used as a supporting structure for installing the aforementioned components. For example, a cylindrical mounting seat surrounding the first flip mechanism 17 and the second flip mechanism 18 can be provided on the side wall of the base to more firmly mount the lifting mechanism 12 of the flip mechanism. The side wall of the base can also be used to drain the cleaning liquid to reduce the dripping and splashing of the liquid, which may contaminate the wafer or the structure in contact with the wafer.

[0098] Optionally, the wafer placement rack 5 can be configured to be able to be raised and lowered. A placement rack lifting device for lifting the wafer placement rack can be provided on the base, so that the wafer placement rack has three lifting positions: low position, middle position, and high position; the wafer placement rack is located at the low position when the loading cup cleans the wafer polishing head and is in the default state; the wafer placement rack is located at the middle position when the loading cup places the wafer, and the wafer placement rack located at the middle position is used to make the bottom of the wafer placed thereon higher than the top of the polishing head cleaning assembly; the wafer placement rack is located at the high position when the loading cup clamps the wafer, and the wafer placement rack located at the high position is aligned with the wafer clamping mechanism.

[0099] Specifically, the center of the base 25 can be raised upward to form a sliding column 27. The middle part of the air film cleaning brush 19 can have a cleaning brush lifting sleeve 24, which is sleeved on the outside of the sliding column 27 and forms a sliding connection therewith; the placement frame lifting sleeve 9 can be sleeved on the outside of the cleaning brush lifting sleeve 24 and forms a sliding connection therewith, and the sliding directions of the placement frame lifting sleeve 9 and the cleaning brush lifting sleeve 24 are parallel, and both can slide up and down relative to the base, so that the wafer placement frame 5 and the air film cleaning brush 19 can slide up and down relative to the base 25. The cleaning brush lifting device and the placement frame lifting device drive the air film cleaning brush 19 and the wafer placement frame 5 to rise and fall respectively. The sliding column, the placement frame lifting sleeve and the cleaning brush lifting sleeve form a sleeve structure, which saves the internal space of the loading cup and makes the structure of the equipment more compact and lighter.

[0100] The present invention also proposes a method for using a loading cup, which includes several uses, including adjusting the loading cup to a default state, placing a wafer, flipping a wafer and cleaning a polishing head, wherein the key lies in the relative position relationship between the wafer placement rack 5, the wafer flipping assembly 11 and the polishing head cleaning device 16.

[0101] To adjust the loading cup to the default state, it is necessary to lower the height of the wafer placement rack, the lifting mechanism, and the polishing head cleaning assembly to the lowest position. Specifically, the lifting mechanism can be in a low position, the base can be in a low position, the air film cleaning brush can be in a low position, the wafer placement rack can be in a low position, and the clamping head can be in a release position.

[0102] When placing the wafer, it is necessary to control the lifting and lowering of the wafer placement rack and the polishing head cleaning assembly so that the bottom of the wafer placed on the wafer placement rack is higher than the top of the polishing head cleaning assembly (such as the air film cleaning brush 19 and the retaining ring cleaning brush 20). At this time, the wafer is placed on the wafer placement rack without touching the polishing head cleaning assembly, which can prevent the liquid on the polishing head cleaning assembly from contaminating the wafer. Specifically, the lifting mechanism can be located in a low position, the base can be located in a high position, the air film cleaning brush can be located in a low position, the wafer placement rack can be located in a middle position, and the clamping head can be located in a release position.

[0103] Fig.10 The present invention is a flow chart of flipping a wafer in the method of using the loading cup of the present invention.

[0104] like Fig.10 As shown, the steps of flipping the wafer include:

[0105] Flipping step I. Clamping the wafer, first, control the lifting and lowering of the lifting mechanism and the wafer placement rack, so that the wafer clamping mechanism 13 installed on the lifting mechanism is aligned with the wafer placement rack 5. At this time, the wafer 1 placed on the wafer placement rack 5 is also at the same height as the wafer clamping mechanism 13, and the wafer clamping mechanism 13 is also aligned with the operating channel 6 on the wafer placement rack 5. Then, control the wafer clamping mechanism 13 to enter the operating channel 6 of the wafer placement rack radially to clamp the wafer 1 placed on the wafer placement rack. Specifically, when clamping the wafer, the lifting mechanism can be located at a low position, the base is located at a low position, the air film cleaning brush is located at a high position, the wafer placement rack is located at a high position, and the clamping head moves from the release position before clamping the wafer to the clamping position.

[0106] Flipping step II. Flip the wafer. First, control the lifting mechanism 12 to lift the wafer clamping mechanism 13 to the highest position. The height of the highest position should be sufficient to allow sufficient space for the flipping of the wafer 1 to avoid the wafer placement rack 5 and the air film cleaning brush; then, rotate the wafer clamping mechanism 180 degrees to flip the wafer 1. Specifically, when flipping the wafer, the lifting mechanism can be located at a high position, the base can be located at a low position, the air film cleaning brush can be located at a low position, the wafer placement rack can be located at a low position, and the clamping head can be located at a clamping position.

[0107] Flipping step III. Put the wafer back, first, control the lifting mechanism to lower the wafer clamping mechanism and the wafer until the wafer clamping mechanism is aligned with the wafer placement rack, then control the wafer clamping mechanism to move radially outward from the operating channel, so as to place the flipped wafer back on the wafer placement rack. Specifically, when putting the wafer back, the lifting mechanism can be located at a low position, the base at a high position, the air film cleaning brush at a low position, the wafer placement rack at a middle position, and the clamping head at a release position.

[0108] Before flipping the wafer, the wafer placement operation needs to be performed first, and the wafer is flipped after the loading cup receives the wafer 1. After flipping the wafer, the base is already in a high position, and the wafer polishing head of the polishing device can transfer the wafer from the loading cup to the polishing turntable.

[0109] Fig.11 The present invention is a flow chart of cleaning the polishing head in the method of using the loading cup of the present invention.

[0110] like Fig.11 As shown, the steps of cleaning the wafer polishing head include:

[0111] Cleaning step I. Raise the polishing head cleaning assembly 16. Specifically, the polishing head cleaning assembly 16, because the size of the wafer polishing head is larger than the wafer, the size of the polishing head cleaning assembly 16 is larger than the wafer, and part of the polishing head cleaning assembly 16 must be extended into the operating channel 6, and pass through the operating channel axially, so that the polishing head cleaning assembly 16 moves from a position lower than the wafer placement rack 5 to the top of the polishing head cleaning assembly higher than the wafer placement rack 5, so as to facilitate the polishing head cleaning assembly to contact the polishing head and not interfere with the wafer placement rack. Specifically, the lifting mechanism can be located at a low position, the base can be located at a high position, the air film cleaning brush can be located at a high position, the wafer placement rack can be located at a low position, and the clamping head can be located at a release position.

[0112] Cleaning step II. Move the polishing head to fit the polishing head cleaning assembly 16, rotate the polishing head to start cleaning, and optionally, the polishing head is connected to a moving device of the CMP equipment, which can be parallel to the polishing head cleaning assembly 16, so that the wafer polishing head can be moved in parallel to a certain extent while rotating to improve the cleaning efficiency. The operation of cleaning the polishing head does not require the aforementioned wafer placement and wafer flipping operations, and can be performed independently.

[0113] Usually, wafer processing only requires polishing one side, and no flipping is required. In the CMP processing of silicon carbide wafers, the carbon side and silicon side of the wafer need to be polished separately. Due to the high polishing pressure of silicon carbide wafers, there is relative sliding between the wafer and the air film of the wafer polishing head, resulting in nano-scale scratches on the edge of the carbon side of the wafer, which is manifested as an obvious white edge area, affecting the quality of wafer polishing. In order to reduce the white edge area, it is necessary to polish both sides of the wafer with a smaller pressure respectively. The loading cup of the present invention is suitable for flipping the wafer for double-sided polishing. Not only that, the loading cup of the present invention includes three functions of placing wafers, flipping wafers and cleaning wafer polishing heads, and the loading cup has flexibility in use. When multiple loading cups of the present invention work at the same time, as long as there is an empty device, any of the above functions can be used to reduce conflicts and shorten waiting time. Compared with single-purpose equipment, this will improve equipment utilization. The same number of loading cups can match a larger number of wafer polishing devices, reducing the floor space and use cost of the equipment.

[0114] The present invention also discloses a wafer polishing device, such as Fig.12 As shown, the polishing device includes a polishing unit 300, a base lifting assembly 200 and a loading cup 100 of the present invention. The polishing unit 300 includes a plurality of key components: a polishing turntable 310, a wafer polishing head 2, a polishing head moving assembly 320, a polishing liquid supply assembly 330 and a trimming assembly 340, and the carrying cup 100 is connected to the base lifting assembly 200. The wafer polishing head can rotate and is used to press the wafer on the polishing turntable for polishing. In addition, there is a negative pressure air film on the wafer polishing head, which can adsorb the wafer and move the wafer. The loading cup 100 is arranged next to the polishing unit 300, and the polishing head moving assembly can move the wafer polishing head, so as to move the wafer adsorbed on the polishing head between the loading cup and the polishing turntable. The loading cup can be used to temporarily place the wafer, flip the wafer and clean the wafer polishing head of the polishing device. When cleaning the wafer polishing head, the wafer polishing head can be moved to the top of the loading cup by the polishing head moving assembly, so that the polishing head rotates, and the loading cup is used to clean the wafer polishing head. The base lifting assembly can lift the loading cup by lifting the base of the loading cup.

[0115] The base can have two lifting positions: low and high. The base is in the low position when the loading cup clamps the wafer, flips the wafer, and is in the default state, and is in the high position when the loading cup places the wafer and cleans the wafer polishing head. As shown in the figure, the base is in the low position when the loading cup clamps the wafer, flips the wafer, and is in the default state. This is because other wafers may be polishing on the polishing turntable at this time. In order to reduce the polishing liquid on the polishing turntable from splashing onto the wafer in the loading cup and causing contamination, the base needs to be lowered to a low position. When placing the wafer and cleaning the wafer polishing head, the loading cup and the wafer polishing head interact. At this time, the base needs to be lifted to a high position and the loading cup needs to be moved to be basically aligned with the polishing turntable. Although it can be slightly higher or lower, it should be within the range of motion of the polishing head moving assembly.

[0116] In addition to being able to move the wafer through the wafer polishing head, the polishing device can also be provided with a wafer moving component for moving the wafer. The wafer moving component can move the wafer to the loading cup for placement or flipping, and can also move the wafer that has been flipped in the loading cup to the next wafer processing process. Through the parallel operation of the wafer polishing head and the wafer moving component, the length of time that the polishing turntable is idle due to the wafer handling caused by the wafer polishing head can be reduced, thereby improving the polishing efficiency. The wafer polishing head can be cleaned after several CMP processes to better avoid damage to the wafer due to crystallization of the polishing liquid remaining on the polishing head, thereby improving the yield rate of the CMP process.

[0117] The present invention also discloses a wafer processing device. The wafer processing device of the present invention utilizes the wafer polishing device of the present invention to perform chemical mechanical polishing. The wafer processing device also includes a processor, a wafer transmission device, a wafer cleaning device, etc., which together with the wafer polishing device control or constitute a controller and device of the wafer processing process flow.

[0118] The technical solution provided by the present invention is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A loading cup, characterized in that: The loading cup comprises a wafer placement rack capable of adjusting height, a wafer flipping assembly and a polishing head cleaning assembly, wherein the wafer placement rack is used to place wafers, the wafer placement rack provides an operation channel, and the wafer flipping assembly and the polishing head cleaning assembly share the operation channel to flip the wafer or clean the wafer polishing head; The wafer flip assembly is arranged on the periphery of the wafer placement rack, and the wafer flip assembly includes a lifting mechanism and a wafer clamping mechanism installed on the lifting mechanism, the lifting mechanism is used to lift the wafer clamping mechanism, and the wafer clamping mechanism can enter the operation channel radially to clamp the wafer when aligned with the wafer placement rack and rotate to flip the wafer after the lifting mechanism lifts the wafer clamping mechanism; as well as, The polishing head cleaning assembly can pass through the operation channel along the axial direction to clean the wafer polishing head.

2. The loading cup according to claim 1, characterized in that: The wafer placement rack includes four arc-shaped components arranged along the circumferential direction. The arc-shaped components are used to support wafers, and the operation channel is formed between adjacent arc-shaped components.

3. The loading cup according to claim 2, characterized in that: A wafer placement rack lifting sleeve is arranged at the center of the wafer placement rack, and the placement rack lifting sleeve is used to lift the arc-shaped component, and the top of the placement rack lifting sleeve is lower than the bottom of the arc-shaped component.

4. The loading cup according to claim 3, characterized in that: The wafer placement rack also includes an inner support frame extending radially and used to connect the arc-shaped component and the placement rack lifting sleeve. The top of the placement rack lifting sleeve is provided with circumferentially distributed lugs, and grooves (31) are formed between adjacent lugs. The radial outer end of the inner support frame is connected to the arc-shaped component, and the radial inner end of the inner support frame extends to the top of the placement rack lifting sleeve and is connected to the lugs.

5. The loading cup according to claim 1, characterized in that: The lifting mechanism has at least two lifting positions, a low position and a high position. The lifting mechanism is at a low position when the loading cup places a wafer, clamps a wafer and cleans a wafer polishing head, and is at a high position when the loading cup flips a wafer.

6. The loading cup according to any one of claims 1 to 5, characterized in that: The wafer clamping mechanism has a clamping head that can be extended and retracted along the radial direction of the wafer placement rack, and the clamping head has a clamping position and a release position. The clamping head is located at the release position when the loading cup places a wafer and cleans the wafer polishing head, and is located at the clamping position when the loading cup clamps the wafer and flips the wafer; The wafer clamping mechanism is rotatably connected to the lifting mechanism, and the wafer clamping mechanism can rotate relative to the lifting mechanism to flip the wafer.

7. The loading cup according to claim 1, wherein: The polishing head cleaning assembly comprises an air film cleaning brush and a retaining ring cleaning brush.

8. The loading cup according to claim 7, characterized in that: The air film cleaning brush extends radially along the wafer placement rack, the radial length of the air film cleaning brush is not less than the radius of the wafer, and the top surface of the air film cleaning brush is provided with bristles.

9. The loading cup according to claim 7 or 8, characterized in that: A cleaning brush lifting device is arranged at the center of the wafer placement rack, and the cleaning brush lifting device is used for lifting the air film cleaning brush, and the air film cleaning brush has at least two lifting positions, a low position and a high position. The air film cleaning brush is located at a low position when the loading cup places the wafer, and is located at a high position when the loading cup clamps the wafer and cleans the wafer polishing head. The top of the air film cleaning brush located at the high position is aligned with the top of the retaining ring cleaning brush.

10. The loading cup according to claim 7, wherein: The polishing head cleaning assembly comprises two retaining ring cleaning brushes, and the retaining ring cleaning brushes are arranged radially opposite to each other on both sides of the wafer placement rack.

11. The loading cup according to claim 7 or 10, characterized in that: The retaining ring cleaning brush is slidably connected to the top of the carrier platform fixedly arranged on the radial outer side of the loading cup, and the retaining ring cleaning brush can reciprocate in a small range in the radial direction or tangential direction.

12. The loading cup according to claim 1, wherein: The two wafer flipping assemblies are arranged radially opposite to each other on both sides of the loading cup, and the two wafer flipping assemblies act synchronously to clamp and flip the wafer.

13. The loading cup according to claim 9, characterized in that The wafer placement rack, the wafer flip assembly and the polishing head cleaning assembly are installed on the same base, the base is cup-shaped, and the side wall of the base surrounds the outer periphery of the loading cup.

14. The loading cup according to claim 13, characterized in that The air film cleaning brush also has a middle lifting position between the low position and the high position. When the wafer is broken, the air film cleaning brush located in the middle position is used to form an operating space for cleaning wafer fragments between the air film cleaning brush and the base.

15. The loading cup according to claim 1, wherein: A wafer rack lifting device is provided at the center of the wafer rack, and the wafer rack lifting device is used to lift the wafer rack, and the wafer rack has three lifting positions: low position, middle position, and high position; The wafer placement rack is located in a low position when the loading cup cleans the wafer polishing head; The wafer placement rack is located in a middle position when the wafer is placed in the loading cup, and the wafer placement rack located in the middle position is used to make the bottom of the wafer placed thereon higher than the top of the polishing head cleaning assembly; The wafer placement rack is located at a high position when the loading cup clamps the wafer, and the wafer placement rack located at a high position is aligned with the wafer clamping mechanism.

16. A loading cup, characterized in that: The loading cup includes a wafer placement rack capable of adjusting height, a wafer flipping assembly, and a polishing head cleaning assembly; The wafer placement rack has at least three lifting positions, namely, low position, middle position and high position; the wafer flip assembly has at least two lifting positions, namely, low position and high position; and the polishing head cleaning assembly has at least two lifting positions, namely, low position and high position; When the wafer placement rack places the wafer, the wafer placement rack is in a middle position, the wafer flipping assembly is in a low position, and the polishing head cleaning assembly is in a low position; When the wafer flipping assembly flips the wafer, the wafer placement rack, the wafer flipping assembly and the polishing head cleaning assembly are all in a high position; When the polishing head cleaning assembly cleans the wafer, the wafer placement rack and the wafer flip assembly are in a low position, and the polishing head cleaning assembly is in a high position.

17. The loading cup according to claim 16, characterized in that The wafer placement rack provides an operation channel, and the wafer flipping assembly and the polishing head cleaning assembly share the operation channel to flip the wafer or clean the wafer polishing head; The wafer flip assembly is arranged on the outer periphery of the wafer placement rack, and the wafer flip assembly includes a wafer clamping mechanism, and the wafer clamping mechanism can enter the operation channel radially to clamp the wafer when the wafer placement rack is in a high position; The polishing head cleaning assembly can axially pass through the operating channel to be in a low position when the wafer placement rack is in a middle position, and axially pass through the operating channel to be in a high position to clean the wafer polishing head when the wafer placement rack is in a low position.

18. A wafer polishing device, characterized in that: The polishing device comprises a polishing unit, a base lifting assembly and a loading cup as claimed in any one of claims 1 to 17; The polishing unit includes a polishing turntable, a wafer polishing head, a polishing head moving assembly, a polishing liquid supply assembly and a trimming assembly, and the bearing cup is connected to a base lifting assembly; The wafer polishing head is used for polishing the wafer on the polishing turntable, and can absorb and move the wafer; The polishing head moving assembly moves the wafer between the loading cup and the polishing turntable by moving the wafer polishing head, and is used to move the wafer polishing head above the loading cup and use the loading cup to clean the wafer polishing head; The base lifting assembly lifts the loading cup by lifting the base of the loading cup. The base has two lifting positions, low and high. The base is at the low position when the loading cup clamps the wafer and flips the wafer, and is at the high position when the loading cup places the wafer and cleans the wafer polishing head.

19. A wafer processing device, characterized in that: The wafer processing equipment performs chemical mechanical polishing using the wafer polishing apparatus as claimed in claim 18.

20. A method for using the loading cup according to any one of claims 1 to 17, characterized in that: The method comprises: Placing the wafer, when placing the wafer, controlling the lifting and lowering of the wafer placement rack and the polishing head cleaning assembly so that the bottom of the wafer placed on the wafer placement rack is higher than the top of the polishing head cleaning assembly; Flip the wafer. The steps of flipping the wafer include: Flipping step I, clamping the wafer, first, controlling the lifting and lowering of the lifting mechanism and the wafer placement rack, so that the wafer clamping mechanism installed on the lifting mechanism is aligned with the wafer placement rack, and then controlling the wafer clamping mechanism to enter the operating channel of the wafer placement rack in the radial direction to clamp the wafer placed on the wafer placement rack; Flipping step II, flipping the wafer, first, controlling the lifting mechanism to lift the wafer clamping mechanism and the wafer to the highest position, then rotating the wafer clamping mechanism 180 degrees to flip the wafer; Flipping step III, putting the wafer back, first, controlling the lifting mechanism to lower the wafer clamping mechanism and the wafer until the wafer clamping mechanism is aligned with the wafer placement rack, then controlling the wafer clamping mechanism to move radially outward from the operation channel, so as to place the flipped wafer back on the wafer placement rack; Cleaning the wafer polishing head. The steps of cleaning the wafer polishing head include: Cleaning step I: raising the polishing head cleaning assembly and passing it through the operating channel axially until its top end is higher than the wafer placement rack. Cleaning step II, moving the wafer polishing head to fit the polishing head cleaning assembly, and rotating the wafer polishing head to start cleaning.

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