Clamping mechanism and wafer cleaning device

Abstract

The invention discloses a clamping mechanism and a wafer cleaning device.The clamping mechanism comprises a plurality of clamping assemblies used for clamping wafers, each clamping assembly comprises a driving part and a clamping part, the clamping parts are arranged on a supporting table, and the driving parts are located below the clamping parts and used for driving clamping jaws of the clamping parts to swing; the multiple clamping assemblies are evenly distributed in the circumferential direction of the supporting table, and every two clamping assemblies are oppositely arranged to form a plurality of clamping sets. The multiple clamping sets have at least two clamping jaw swing angle ranges. By adopting the technical scheme, the defect that the wafer is easily jacked by the clamping jaw in the process of feeding the wafer through the manipulator in the prior art is overcome, and the tolerance to the transverse stroke error of the manipulator is remarkably improved, so that the manipulator can better adapt to the deviation in actual operation, the smoothness of the clamping process is ensured, and the working efficiency is improved.

Description

Technical Field

[0001] The invention relates to a clamping mechanism and a wafer cleaning device, belonging to the technical field of chip manufacturing. Background Art

[0002] Wafer cleaning is a very critical part of the chip manufacturing process. It is mainly used to remove pollutants and impurities on the surface of the wafer to ensure the quality and reliability of subsequent processes. Wafers undergo multiple cleanings during the manufacturing process, and the cleaning effect directly affects the performance and yield of the chip. The purpose of wafer cleaning is to remove particles, organic pollutants and metal impurities on the surface of the wafer. There may be tiny particles on the surface of the wafer. If they are not removed, these particles may cause defects in the subsequent photolithography and etching processes and affect the formation of the circuit; organic matter such as photoresist residues and grease will affect the deposition and etching processes of the film and need to be removed during the cleaning process; there may be metal ion contamination during the manufacturing process. Metal impurities may cause the electrical performance of the device to deteriorate and need to be removed during cleaning. Wet cleaning is the most common cleaning method, which is to use chemical solutions to clean the wafer. During the wet cleaning process, the wafer needs to be clamped first to ensure the stability of the wafer during the cleaning process, avoid mechanical stress or damage, and ensure that the cleaning solution can evenly cover the surface of the wafer to achieve the best cleaning effect. During the wafer cleaning process, it is crucial to clamp and fix the wafer, which ensures the stability of the wafer during the cleaning process and avoids damage or contamination caused by movement or shaking. The common way to fix the wafer is to clamp it with a mechanical clamp, usually using a clamp to clamp the wafer from the edge of the wafer. This method can fix the wafer and ensure that it does not shift during the cleaning process. At the same time, since the clamp only contacts the edge of the wafer, it avoids contamination of the wafer surface.

[0003] Since the clamping process is carried out in an environment containing a large amount of chemical solutions, the clamping components and transmission components are exposed to the chemical solutions, which can easily cause some components to be corroded by the chemical solutions, resulting in degradation or failure of the fixture performance; at the same time, the components may also be contaminated due to contact with the cleaning solution, and long-term use may lead to accumulation of residues, thereby affecting the cleaning effect; when maintaining the components, the complex structure will also increase the complexity and maintenance cost of the maintenance operation.

[0004] In addition, during the wafer cleaning process, the entire cleaning device is placed in a closed cover. Before cleaning, the wafer needs to be sent into the closed cover horizontally by a robot. After reaching the position, the wafer is released downward and clamped and fixed by the clamping parts below. However, since there are often errors in the stroke of the robot to transport the wafer horizontally, the wafer and the pair of clamps in the transport direction cannot be aligned. In other words, when the position of the wafer transported horizontally by the robot exceeds the standard position or does not reach the standard position, it is easy to be supported by the clamp on one side when it is lowered, and it cannot be placed between the pair of clamps. Summary of the invention

[0005] Therefore, the purpose of the present invention is to overcome the defect in the above-mentioned prior art that the wafer is easily held up by the clamping claws during the process of feeding the wafer by a robot, thereby providing a clamping mechanism and a wafer cleaning device.

[0006] In order to achieve the above-mentioned purpose, a clamping mechanism of the present invention includes multiple clamping components for clamping wafers, the clamping components include a driving part and a clamping part, the clamping part is arranged on a support table, and the driving part is located below the clamping part and is used to drive the clamping claws of the clamping part to swing; the multiple clamping components are evenly distributed in the circumferential direction of the support table, and the multiple clamping components are arranged opposite to each other in pairs to form multiple clamping groups; wherein the multiple clamping groups have at least two clamping claw swing angle ranges, and the clamping components in the same group have the same swing angle range.

[0007] The clamping part also includes a lifting rod and a rocker arm. The clamping claw is fixedly connected to the rocker arm and installed on the support platform through a rotating shaft. The clamping claw protrudes upward from the table surface of the support platform. The lifting rod is connected to the rocker arm through a linkage structure to drive the rocker arm to swing around the rotating shaft.

[0008] The linkage structure comprises a guide shaft pin arranged on the lifting rod and a long hole opened on the swing rod. The guide shaft pin is inserted into the long hole and can move relatively in the long hole.

[0009] The length of the long hole in the clamping group with a larger jaw swing angle range is greater than the length of the long hole in other clamping groups.

[0010] The long direction of the long hole is inclined relative to the horizontal plane.

[0011] There are two swing rods, which are respectively arranged on the left and right sides of the lifting rod, and the clamping claw is fixedly connected to one of the swing rods.

[0012] The two swing rods are symmetrically arranged on the left and right sides of the lifting rod.

[0013] The difference in the swing angle range of two clamping jaws in the multiple clamping groups is 3° to 4.5°.

[0014] There are four clamping assemblies, and the four clamping assemblies are arranged opposite to each other in pairs to form two clamping groups.

[0015] At least one supporting needle is also fixed on the inner side of each clamping jaw.

[0016] The clamping part also includes a return spring, and the return spring is pressed against the top end of the lifting rod; the driving part is used to move up and lift up the lifting rod, and to move down and detach from the lifting rod.

[0017] A sealing sleeve is arranged on the lower end surface of the support platform, and the top end of the lifting rod is inserted into the sealing sleeve and can slide along the sealing sleeve; the return spring is arranged in the sealing sleeve and pressed between the lifting rod and the support platform.

[0018] The lifting rod comprises a sleeve portion located at the top, the lower end of the return spring is inserted into the sleeve portion, and the sleeve portion and the sealing sleeve are slidably and sealingly matched with each other.

[0019] The driving part includes a lifting device and a push rod device, wherein the lifting device is used to drive the push rod device to rise and fall; the push rod device includes a push rod part and a cap part located at the top end of the push rod part, wherein the cap part is used to lift the lifting rod upward.

[0020] The cap portion includes a connection portion connected to the push rod portion and a lifting portion extending radially outward from the support platform, and the lifting portion is used to contact the lifting rod.

[0021] A base is arranged below the support platform, the lifting device is arranged in the base, and the push rod part passes upward through the through hole on the base; a first sealing component is arranged outside the through hole, and a second sealing component is arranged between the first sealing component and the cap part.

[0022] The second sealing assembly includes a bellows, the upper end of which is connected to the upper part of the top rod portion, and the lower end of which is connected to the first sealing assembly.

[0023] The first sealing assembly comprises a guide sleeve and at least one sealing ring arranged on the outside of the guide sleeve; the guide sleeve is sleeved on the outside of the push rod part.

[0024] The second sealing assembly comprises a sealing sleeve, the upper portion of which is sealingly connected to the push rod portion, and the top of the guide sleeve is inserted into the lower end of the sealing sleeve and is slidingly and sealingly connected to the sealing sleeve.

[0025] The upper part of the sealing sleeve is screwed onto the push rod part, and the top end of the sealing sleeve and the push rod part are sealed by a sealing ring.

[0026] The present invention also provides a wafer cleaning device, comprising a cleaning part and a closed cover, the cleaning part comprising the clamping mechanism as described above and a rotating drive mechanism arranged under the support table, the rotating drive mechanism is used to drive the support table to rotate; a loading door is provided on the closed cover, which is used for a loading robot to laterally feed the wafer into the closed cover; a clamping group with a larger jaw swing angle range in the clamping mechanism is arranged in the lateral feeding direction of the loading robot.

[0027] At least one retaining ring is arranged on the radial outer side of the cleaning part, and the retaining ring is used to block and recover the cleaning liquid during the wafer cleaning process; a retaining ring lifting mechanism is arranged below the retaining ring.

[0028] By adopting the above technical solution, the clamping mechanism and wafer cleaning device of the present invention have the following beneficial effects compared with the prior art:

[0029] 1. Increase the swing angle of the clamping jaws in one clamping group, so that a larger opening angle can be formed between the two clamping jaws in the direction in which the robot feeds the wafer laterally, which has a higher tolerance for the lateral travel error of the robot and avoids the obstruction of the wafer caused by the clamping jaws opening angle being too small; at the same time, the opening angle between the two clamping jaws of other clamping groups is smaller. When the wafer is lowered, the clamping jaws of other clamping groups can still pre-support the wafer. Then the robot releases the wafer to keep the wafer at the pre-support height, and then resets the clamping jaws to complete the clamping of the wafer.

[0030] 2. By setting a linkage mechanism in which the guide shaft pin and the long hole cooperate with each other, the lifting action of the lifting rod is converted into the swinging action of the rocker arm and the clamping claw, and different clamping claw swing angles can be achieved by setting the long hole to different lengths. The structure is very simple and the operation is relatively stable.

[0031] 3. Support pins are fixed on the inner side of the clamp to pre-support the wafer when placing it. When the clamp closes to clamp the wafer, the clamp and the support pins rotate synchronously at a small angle, so that the top of the support pin is detached from the wafer while the clamp clamps the wafer, avoiding damage to the wafer surface during the cleaning rotation process.

[0032] 4. Two swing arms are arranged in one clamping part, and the two swing arms are arranged on the left and right sides of the lifting rod respectively, forming a symmetrical transmission structure, so that the clamping part is subjected to more balanced force when being lifted, the movement of the components is smoother, and the unidirectional wear caused by long-term uneven force on the components is avoided.

[0033] 5. The driving part and the clamping part are arranged as two parts separated from each other. When lifting, an upward force is applied to the lifting rod through the jacking rod device, and a reset spring is arranged at the same time to realize the reset of the lifting rod, which simplifies the installation structure and sealing structure of the clamping mechanism, so that the driving part and the clamping part can be installed independently, maintenance is more convenient, and better sealing effect can be achieved.

[0034] 6. The design of multi-layer sealing components effectively prevents the leakage of chemical solutions and further protects the internal mechanical structure.

[0035] 7. The clamping mechanism and wafer cleaning device of the present invention have a reasonable overall design structure, which enhances the reliability of the clamping device under different operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic structural diagram of the wafer cleaning device of the present invention.

[0037] Figure 2 It is a schematic diagram of the structure of the cleaning unit.

[0038] Figure 3 It is a schematic diagram of the distribution of the first clamping group and the second clamping group on the support platform.

[0039] Figure 4 It is a schematic diagram of the structure of the clamping part.

[0040] Figure 5 It is a side view of the clamping part.

[0041] Figure 6 A partial cross-sectional view of the assembly structure of the first embodiment of the clamping assembly.

[0042] Figure 7 It is a cross-sectional view of the second embodiment of the clamping assembly.

[0043] Figure 8 Schematic diagram of the distribution of six clamping components on the support table. DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the embodiments of the present application should fall within the scope of protection of the embodiments of the present application.

[0045] In the description of the present application, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0046] In addition, in the description of the present application, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal connection between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0047] The present invention is further described in detail below through the accompanying drawings and specific embodiments.

[0048] At present, for the wet processing of wafers (such as single-wafer cleaning), the horizontal cleaning and double-sided cleaning processes of wafers account for an increasing proportion in the high-end process. This cleaning process usually uses a horizontal wafer cleaning device, and its specific operation mode is: the wafer is clamped horizontally by claws, and the claws are driven by power components (such as motors) to drive the wafer to rotate. During the rotation of the wafer, the front of the wafer is cleaned by spraying chemical liquid on the front of the wafer. For the back cleaning process, it is necessary to spray chemical liquid from the back of the wafer. In order to increase the production capacity of the machine and accelerate the drying process of the wafer, it is usually supplemented by a purge function that provides high-purity nitrogen.

[0049] like Figure 1-Figure 3 As shown, the present invention provides a specific wafer cleaning device, including a cleaning portion 1 and a sealing cover 2 , wherein the cleaning portion 1 is arranged inside the sealing cover 2 .

[0050] The cleaning unit 1 includes a central rotating support mechanism 100 and a clamping mechanism 200 . The central rotating support mechanism 100 includes a support table 11 , a base 12 located below the support table 11 , and a rotating drive mechanism 17 located in the base 12 . The rotating drive mechanism is used to drive the support table 11 to rotate.

[0051] In this embodiment, the clamping mechanism 200 includes four clamping components 21 for clamping the wafer 90. The clamping components 21 include a driving part 211 and a clamping part 212. The clamping part 212 is disposed on the support platform 11. The driving part 211 is located below the clamping part 212 and is used to drive the clamping claw 201 of the clamping part 212 to swing. Figure 3 As shown, the four clamping assemblies 21 are evenly distributed in the circumferential direction of the support platform 11, and the four clamping assemblies 21 are arranged opposite to each other in pairs to form two clamping groups, namely, a first clamping group 21a and a second clamping group 21b. Of course, in other embodiments, the clamping assemblies 21 may also be other numbers, such as Figure 8 As shown, there are six clamping assemblies 21 .

[0052] The multiple clamping assemblies 21 are evenly distributed in the circumferential direction of the support table 11, and the multiple clamping assemblies 21 are arranged opposite to each other in pairs to form multiple clamping groups; wherein the multiple clamping groups have at least two jaw swing angle ranges, the jaw swing angle ranges of the clamping assemblies in the same group are the same, and the two jaw swing angle ranges of the clamping group arranged in the lateral feeding direction of the loading robot are larger.

[0053] The enclosed cover 2 is provided with a loading door 20 for a loading robot (not shown) to laterally feed the wafer into the enclosed cover 2. In the present embodiment, the first clamping group 21a is arranged in the lateral feeding direction F of the loading robot, and the swing angle range of the clamping jaws 201 in the first clamping group 21a is greater than the swing angle range of the clamping jaws 201 in the second clamping group 21b. Most preferably, the swing angle range of the clamping jaws 201 in the first clamping group 21a is 3° to 4.5° greater than the swing angle range of the clamping jaws 201 in the second clamping group 21b, so that a larger opening angle can be formed between the two clamping jaws 201 in the direction in which the robot laterally feeds the wafer, which has a higher tolerance for the lateral travel error of the robot, and avoids the clamping jaws 201 from blocking the wafer due to too small an opening angle. At the same time, the angle between the two clamping jaws 201 of the second clamping group 21b part 21 is smaller than the angle between the two clamping jaws 201 in the first clamping group 21a part 21. When the wafer is lowered into the second clamping group 21b part 21, the clamping jaws 201 of the second clamping group 21b part 21 can still pre-support the wafer. Then the robot releases the wafer to keep the wafer at the pre-support height, and then resets the clamping jaws 201 to complete the clamping of the wafer.

[0054] like Figure 4 , Figure 5 As shown, the clamping part 212 includes a clamping jaw 201, a lifting rod 202 and a swing rod 203. The clamping jaw 201 is fixedly connected to the swing rod 203 and is installed on the support platform 11 through a rotating shaft 205. The clamping jaw 201 protrudes upward from the surface of the support platform 11. At least one supporting pin 204 is also fixed on the inner side of each of the clamping jaws 201. In this embodiment, there are two supporting pins 204, which are spaced apart. The lifting rod 202 is connected to the swing rod 203 through a linkage structure, which is used to drive the swing rod 203 to swing around the rotating shaft 205, so that the clamping jaw 201 and the supporting pin 204 swing synchronously. The support pins 204 can be used to pre-support the wafer when placing it, that is, when the jaws 201 are opened, the wafer is lowered onto the support pins 204. In the subsequent closing process of the jaws 201, the jaws 201 and the support pins 204 rotate synchronously at a small angle, so that the top of the support pins 204 are detached from the wafer while the jaws 201 clamp the edge side wall of the wafer, thereby avoiding damage to the lower surface of the wafer during the cleaning rotation process.

[0055] In this embodiment, the linkage structure includes a guide pin 202a provided on the lifting rod 202 and a long hole 203a provided on the swing rod 203. The long direction of the long hole 203a is inclined relative to the horizontal plane. The guide pin 202a is inserted into the long hole 203a and can move relatively in the long hole 203a. The relative movement of the guide pin 202a in the long hole 203a helps to accurately control the swing angle of the clamping jaw 201 and improve the clamping accuracy. The inclined long hole 203a has a better guiding effect on the guide pin 202a and reduces the friction loss during use. At the same time, the inclined structure design reduces the lateral deviation during swinging, ensuring the stability of the clamping part 212 during operation. This design reduces complex mechanical connections, reduces the failure rate, and simplifies maintenance work.

[0056] There are two swing rods 203, which are respectively arranged on the left and right sides of the lifting rod 202 to form a symmetrical transmission structure, and the clamping claw 201 is fixedly connected to one of the swing rods 203. The symmetrical transmission structure formed by the two swing rods 203 can make the clamping part 212 more evenly stressed when being lifted, make the movement of the components smoother, and avoid unidirectional wear caused by uneven stress on the components for a long time.

[0057] The length of the long hole 203a in the first clamping group 21a is greater than the length of the long hole 203a in the second clamping group 21b. The relative movement stroke interval of the guide shaft pin 202a in the long hole 203a starts from one end of the long hole 203a to the other end of the long hole 203a. By changing the length of the long hole 203a, the relative movement stroke of the guide shaft pin 202a can be limited. The different lengths of the long holes 203a in the first clamping group 21a and the second clamping group 21b can ultimately achieve different swing angle amplitudes of the respective clamping jaws 201. Therefore, by setting the length of the long hole 203a in the first clamping group 21a to be greater than the length of the long hole 203a in the second clamping group 21b, the swing angle of the clamping jaw 201 in the first clamping group 21a can be greater than the swing angle of the clamping jaw 201 in the second clamping group 21b. This structure is very simple to implement and relatively stable in operation.

[0058] In order to improve the sealing performance of the structure, prevent key components from being corroded by chemical solutions or intruded by dirt, and also to achieve a simpler installation and maintenance structure, the clamping assembly 21 in the present invention arranges the driving part 211 and the clamping part 212 into two independent and separable parts.

[0059] like Figure 6As shown, in the first embodiment of the clamping assembly 21, the clamping part 212 further includes a reset spring 206, and the reset spring 206 is pressed against the top end of the lifting rod 202; the driving part 211 is used to move up and lift the lifting rod 202, and to move down and disengage from the lifting rod 202. A sealing sleeve 207 is provided on the lower end surface of the support platform 11, and the top end of the lifting rod 202 is inserted into the sealing sleeve 207 and can slide along the sealing sleeve 207; the reset spring 206 is provided in the sealing sleeve 207 and is pressed between the lifting rod 202 and the support platform 11. The lifting rod 202 includes a sleeve part 202b located at the top, and the lower end of the reset spring 206 is inserted into the sleeve part 202b, and the sleeve part 202b and the sealing sleeve 207 are slidably and sealedly matched with each other.

[0060] The driving part 211 includes a lifting device 221a and a push rod device 221b. The lifting device 221a is used to drive the push rod device 221b to move up and down, and can be a linear driving device such as a cylinder or a motor push rod. The push rod device 221b includes a push rod part 208 and a cap part 209 located at the top of the push rod part 208. The cap part 209 is used to lift the lifting rod 202 upward.

[0061] The reset spring 206 is designed to provide a reset force to the clamping part 212 and a clamping force to the wafer, and has high operability, high efficiency and reliability. At the same time, the setting of the reset spring 206 also enhances the stability during the clamping process, ensuring that the clamping jaws 201 will not loosen due to external forces during clamping. The elasticity of the reset spring 206 can effectively absorb external impacts and improve the overall adaptability and reliability of the system. The mutual sliding seal of the sealing sleeve 207 and the sleeve part 202b prevents leakage of the cleaning liquid, protects the reset spring 206 from chemical corrosion, and prolongs the service life of the components.

[0062] A base 12 is arranged below the support platform 11, the lifting device 221a is arranged in the base 12, and the push rod part 208 passes upward through the through hole on the base 12; a first sealing component is arranged on the outside of the through hole, and a second sealing component is arranged between the first sealing component and the cap part 209.

[0063] In this embodiment, the first sealing component is a guide sealing ring 231 , and the second sealing component includes a bellows 232 . The upper end of the bellows 232 is connected to the upper part of the top rod 208 , and the lower end is connected to the guide sealing ring 231 .

[0064] like Figure 7As shown, in the second embodiment of the clamping assembly 21, the first sealing assembly includes a guide sleeve 233 and a plurality of sealing rings 234 arranged on the outside of the guide sleeve 233, and the sealing rings 234 are used to form a seal between the guide sleeve 233 and the base 12; the guide sleeve 233 is sleeved on the outside of the top rod 208. The second sealing assembly includes a sealing sleeve 235, the upper part of which is sealed and connected with the top rod 208. Specifically, the upper part of the sealing sleeve 235 is screwed on the top rod 208, and the top end of the sealing sleeve 235 is sealed with the top rod 208 through a sealing ring 236. The top of the guide sleeve 233 is inserted into the lower end of the sealing sleeve 235 and is slidably sealed and connected with the sealing sleeve 235.

[0065] The driving part 211 and the clamping part 212 are set as two parts separated from each other. When lifting, the lifting rod 202 is exerted with an upward force through the push rod device 221b, and the reset spring 206 is set to reset the lifting rod 202, which simplifies the installation structure and sealing structure of the clamping mechanism 200, so that the driving part 211 and the clamping part 212 can be installed independently, which is more convenient for maintenance and can achieve a better sealing effect. At the same time, the design of the multi-layer sealing component also effectively prevents the leakage of chemical solutions and further protects the internal mechanical structure.

[0066] The cap portion 209 includes a connection portion connected to the push rod portion 208 and a lifting portion 209a extending radially outward from the support platform 11, and the lifting portion 209a is used to contact the lifting rod 202. A larger cap portion 209 structure is arranged at the top of the push rod portion 208, which can realize the lifting effect of the driving portion 211 and the clamping portion 212 under the condition of non-centering, so that the driving portion 211 located at the bottom can be arranged as close to the center of the cleaning portion 1 as possible, making the structure more compact.

[0067] A first retaining ring 13 and a second retaining ring 14 are provided radially outside the cleaning part 1. The first retaining ring 13 and the second retaining ring 14 are used to block and recover the cleaning liquid during the wafer cleaning process. A first lifting mechanism 15 and a second lifting mechanism 16 are provided below the first retaining ring 13 and the second retaining ring 14, respectively, for driving the lifting thereof.

[0068] Obviously, the above embodiments are only examples for clear explanation, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from them are still within the protection scope of the invention.

Claims

1. A clamping mechanism, characterized in that: It comprises a plurality of clamping assemblies for clamping wafers, wherein the clamping assemblies comprise a driving part and a clamping part, wherein the clamping part is arranged on a supporting platform, and the driving part is located below the clamping part and is used for driving the jaws of the clamping part to swing; the plurality of clamping assemblies are evenly distributed in the circumferential direction of the supporting platform, and the plurality of clamping assemblies are arranged opposite to each other in pairs to form a plurality of clamping groups; wherein the plurality of clamping groups have at least two jaw swing angle ranges, and the jaw swing angle ranges of the clamping assemblies in the same group are the same.

2. The clamping mechanism according to claim 1, characterized in that: The clamping part also includes a lifting rod and a rocker arm. The clamping claw is fixedly connected to the rocker arm and installed on the support platform through a rotating shaft. The clamping claw protrudes upward from the table surface of the support platform. The lifting rod is connected to the rocker arm through a linkage structure to drive the rocker arm to swing around the rotating shaft.

3. The clamping mechanism according to claim 2, characterized in that: The linkage structure comprises a guide shaft pin arranged on the lifting rod and a long hole opened on the swing rod. The guide shaft pin is inserted into the long hole and can move relatively in the long hole.

4. The clamping mechanism according to claim 3, characterized in that: The length of the long hole in the clamping group with a larger jaw swing angle range is greater than the length of the long hole in other clamping groups.

5. The clamping mechanism according to claim 3, characterized in that: The long direction of the long hole is inclined relative to the horizontal plane.

6. The clamping mechanism according to claim 3, characterized in that: There are two swing rods, which are respectively arranged on the left and right sides of the lifting rod, and the clamping claw is fixedly connected to one of the swing rods.

7. The clamping mechanism according to claim 6, characterized in that: The two swing rods are symmetrically arranged on the left and right sides of the lifting rod.

8. The clamping mechanism according to claim 1, characterized in that: The difference in the swing angle range of two clamping jaws in the multiple clamping groups is 3° to 4.5°.

9. The clamping mechanism according to claim 1, characterized in that: There are four clamping assemblies, and the four clamping assemblies are arranged opposite to each other in pairs to form two clamping groups.

10. The clamping mechanism according to claim 1, characterized in that: At least one supporting needle is also fixed on the inner side of each clamping jaw.

11. The clamping mechanism according to any one of claims 2 to 7, characterized in that: The clamping part also includes a return spring, and the return spring is pressed against the top end of the lifting rod; the driving part is used to move up and lift up the lifting rod, and to move down and detach from the lifting rod.

12. The clamping mechanism according to claim 11, characterized in that: A sealing sleeve is arranged on the lower end surface of the support platform, and the top end of the lifting rod is inserted into the sealing sleeve and can slide along the sealing sleeve; the return spring is arranged in the sealing sleeve and pressed between the lifting rod and the support platform.

13. The clamping mechanism according to claim 12, characterized in that: The lifting rod comprises a sleeve portion located at the top, the lower end of the return spring is inserted into the sleeve portion, and the sleeve portion and the sealing sleeve are slidably and sealingly matched with each other.

14. The clamping mechanism according to any one of claims 2 to 7, characterized in that: The driving part includes a lifting device and a push rod device, wherein the lifting device is used to drive the push rod device to rise and fall; the push rod device includes a push rod part and a cap part located at the top end of the push rod part, wherein the cap part is used to lift the lifting rod upward.

15. The clamping mechanism according to claim 14, characterized in that: The cap portion includes a connection portion connected to the push rod portion and a lifting portion extending radially outward from the support platform, and the lifting portion is used to contact the lifting rod.

16. The clamping mechanism according to claim 14, characterized in that: A base is arranged below the support platform, the lifting device is arranged in the base, and the push rod part passes upward through the through hole on the base; a first sealing component is arranged outside the through hole, and a second sealing component is arranged between the first sealing component and the cap part.

17. The clamping mechanism according to claim 16, characterized in that: The second sealing assembly includes a bellows, the upper end of which is connected to the upper part of the top rod portion, and the lower end of which is connected to the first sealing assembly.

18. The clamping mechanism according to claim 16, characterized in that: The first sealing assembly comprises a guide sleeve and at least one sealing ring arranged on the outside of the guide sleeve; the guide sleeve is sleeved on the outside of the push rod part.

19. The clamping mechanism according to claim 18, characterized in that: The second sealing assembly comprises a sealing sleeve, the upper portion of which is sealingly connected to the push rod portion, and the top of the guide sleeve is inserted into the lower end of the sealing sleeve and is slidingly and sealingly connected to the sealing sleeve.

20. The clamping mechanism according to claim 19, characterized in that: The upper part of the sealing sleeve is screwed onto the push rod part, and the top end of the sealing sleeve and the push rod part are sealed by a sealing ring.

21. A wafer cleaning device, characterized in that: It includes a cleaning part and a closing cover, the cleaning part includes a clamping mechanism as described in any one of claims 1 to 20 and a rotating drive mechanism arranged under the support table, the rotating drive mechanism is used to drive the support table to rotate; a loading door is provided on the closing cover, which is used for a loading robot to laterally feed the wafer into the closing cover; a clamping group with a larger jaw swing angle range in the clamping mechanism is arranged in the lateral feeding direction of the loading robot.

22. The wafer cleaning device according to claim 21, characterized in that: At least one retaining ring is arranged on the radial outer side of the cleaning portion, and the retaining ring is used to block and recover the cleaning liquid; a retaining ring lifting mechanism is arranged below the retaining ring.

Images