Grinding mechanism and chemical mechanical grinding device

Abstract

The invention provides a grinding mechanism and a chemical mechanical grinding device.The grinding mechanism comprises a grinding gasket and a grinding assembly, the grinding gasket is used for grinding a target wafer, the grinding assembly is located on the side, away from the grinding gasket, of the target wafer and comprises a grinding head and a pressure diaphragm, and the pressure diaphragm is connected to the grinding head; the pressure diaphragm comprises a diaphragm body and a convex ring structure, the convex ring structure is arranged on the side, facing the target wafer, of the diaphragm body in a protruding mode, the target wafer is at least partially contained in the convex ring structure in the axial direction of the target wafer, a first pressure cavity is formed in the side, deviating from the grinding gasket, of the convex ring structure, and a second pressure cavity is formed in the side, deviating from the grinding gasket, of the convex ring structure. Under the action of gas pressure in the first pressure cavity, the convex ring structure enables the edge portion of the target wafer to be tightly attached to the grinding gasket, and therefore the grinding quality of the target wafer is guaranteed.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor manufacturing technology, and more specifically, to a grinding mechanism and a chemical mechanical grinding device. Background Art

[0002] Chemical Mechanical Polishing, also known as chemical mechanical planarization, is a technology that flattens the surface of a wafer. During the polishing process, the wafer rotates on the polishing pad driven by the wafer polishing assembly, and with the help of chemical polishing agents, the surface material of the wafer is removed through the combined action of mechanical polishing and chemical corrosion, thereby achieving global flattening.

[0003] Chemical mechanical polishing is widely used in the polishing of metal and non-metal layers on wafers, and is also one of the fastest growing areas of semiconductor technology. During the chemical mechanical polishing process, the flatness of the wafer surface is extremely important for improving the yield.

[0004] However, when the existing chemical mechanical polishing equipment polishes the wafer, the pressure chamber set on the pressure diaphragm provides pressure to the wafer. Since the polishing pad is made of soft material, when the wafer rotates on the polishing pad, the part of the polishing pad close to the edge of the wafer will deform, so that the pressure diaphragm cannot maintain the pressure at the edge of the wafer within a preset range, thereby affecting the polishing quality of the wafer. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a grinding mechanism and a chemical mechanical grinding device to solve the technical problem in the prior art that the pressure applied to the edge of the wafer by the chemical mechanical grinding device during the wafer grinding process cannot be maintained within a preset pressure range.

[0006] To achieve the above objectives, the first aspect of the present application is to provide a grinding mechanism, comprising: A grinding pad, connected to a preset position and rotating about a preset rotation axis, for grinding a target wafer; A grinding assembly, located on a side of the target wafer away from the grinding pad, comprising a grinding head and a pressure diaphragm; The pressure diaphragm is connected to the grinding head, and the pressure diaphragm includes a diaphragm body and a convex ring structure, wherein the convex ring structure is convexly arranged on a side of the diaphragm body facing the target wafer, and along the axial direction of the target wafer, the target wafer is at least partially accommodated in the convex ring structure; A first pressure chamber is provided on the side of the convex ring structure away from the grinding pad. Under the action of the gas pressure in the first pressure chamber, the convex ring structure can make the edge of the target wafer fit onto the grinding pad.

[0007] Optionally, the convex ring structure includes: A first diaphragm extending along the axial direction of the target wafer and integrally provided with the diaphragm body; A second diaphragm extending in the radial direction of the target wafer and integrally provided with an end of the first diaphragm away from the diaphragm body; A third diaphragm extends along the axial direction of the target wafer and is integrally provided with an end of the second diaphragm away from the first diaphragm; The first pressure chamber is formed between the first diaphragm, the second diaphragm and the third diaphragm.

[0008] Optionally, A first rounded corner is provided at a connection portion between the second diaphragm and the first diaphragm; A second rounded corner is provided at a connection position between the third diaphragm and the second diaphragm.

[0009] Optionally, the convex ring structure further includes: The reinforcing diaphragm is located in the first pressure chamber, and one end of the reinforcing diaphragm is integrally arranged with the first diaphragm, and the other end opposite to the one end is integrally arranged with the second diaphragm.

[0010] Optionally, a plurality of second pressure chambers are provided on the diaphragm body, the plurality of second pressure chambers are arranged in sequence along the radial direction of the target wafer, and the plurality of pressure chambers are independent of each other.

[0011] Optionally, it also includes: An edge ring is slidably connected to the grinding head along the circumference of the target wafer and is located outside the pressure diaphragm, and the edge ring abuts against the grinding pad; A bidirectional flow channel is provided on one side of the edge ring facing the grinding pad, and the bidirectional flow channel is used for flowing into the edge of the target wafer or flowing out of the target wafer from the edge of the target wafer.

[0012] Optionally, A plurality of columnar protrusions are convexly provided on one side of the edge ring facing the grinding pad, and the plurality of columnar protrusions are evenly spaced along the circumference of the edge ring; The bidirectional flow channel is formed between any two adjacent columnar protrusions.

[0013] Optionally, a fourth diaphragm is provided on a side of the convex ring structure away from the target wafer, the fourth diaphragm comprises a first sub-diaphragm extending radially along the target wafer and a second sub-diaphragm arranged at an angle to the first sub-diaphragm, the first sub-diaphragm and the second sub-diaphragm being arranged integrally; A third pressure chamber is formed between the first sub-diaphragm, the first sub-diaphragm and a side of the convex ring structure facing away from the target wafer; A boss matched with the first sub-diaphragm is provided on the inner side of the grinding head or the edge ring, and under the action of the pressure of the third pressure chamber along the circumference of the target wafer, the first sub-diaphragm fits with the boss.

[0014] Optionally, a fifth diaphragm is disposed on the side wall of the first pressure chamber away from the target wafer, and a fourth pressure chamber is formed between the fifth diaphragm and the side wall of the first pressure chamber away from the target wafer.

[0015] The beneficial effect of the grinding mechanism provided by the present application is that: compared with the prior art, the grinding mechanism provided by the present application includes a grinding pad and a grinding assembly, wherein the grinding pad is rotatably connected to a preset position for grinding a target wafer, and the grinding assembly is located on the side of the target wafer away from the grinding pad, and includes a grinding head and a pressure diaphragm, and the pressure diaphragm is connected to the grinding head; the pressure diaphragm includes a diaphragm body and a convex ring structure, the convex ring structure is convexly arranged on the side of the diaphragm body facing the target wafer, and the target wafer is at least partially accommodated in the convex ring structure along the axial direction of the target wafer, and a first pressure chamber is provided on the side of the convex ring structure away from the grinding pad, and under the action of the gas pressure in the first pressure chamber, the convex ring structure makes the edge of the target wafer fit tightly with the grinding pad, thereby ensuring the grinding quality of the target wafer.

[0016] In a second aspect, the present application provides a chemical mechanical polishing device, comprising: The grinding mechanism is any one of the grinding mechanisms described above.

[0017] The beneficial effect of the chemical mechanical polishing device provided by the present application is that: compared with the prior art, the chemical mechanical polishing device provided by the present application includes a polishing mechanism provided by any one of the above items, the polishing mechanism includes a polishing pad and a polishing assembly, wherein the polishing pad is rotatably connected to a preset position for polishing a target wafer, the polishing assembly is located on the side of the target wafer away from the polishing pad, and includes a polishing head and a pressure diaphragm, the pressure diaphragm is connected to the polishing head; the pressure diaphragm includes a diaphragm body and a convex ring structure, the convex ring structure is convexly arranged on the side of the diaphragm body facing the target wafer, along the axial direction of the target wafer, the target wafer is at least partially accommodated in the convex ring structure, and a first pressure chamber is provided on the side of the convex ring structure away from the polishing pad, under the action of the gas pressure in the first pressure chamber, the convex ring structure makes the edge of the target wafer fit tightly with the polishing pad, thereby ensuring the polishing quality of the target wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 A schematic diagram of the structure of a chemical mechanical polishing device provided in an embodiment of the present application; Figure 2 A schematic diagram of the grinding mechanism structure provided in an embodiment of the present application; Figure 3 A schematic diagram of the structure of the grinding mechanism provided in the embodiment of the present application when it cooperates with the target wafer; Figure 4 A schematic diagram of the structure of a pressure diaphragm provided in an embodiment of the present application; Figure 5 A schematic structural diagram of a pressure diaphragm provided in another embodiment of the present application; Figure 6 A schematic diagram of the grinding mechanism structure provided in another embodiment of the present application; Figure 7 A schematic diagram of the grinding mechanism structure provided in another embodiment of the present application; Figure 8 A schematic diagram of the structure of the second gas flow channel provided in an embodiment of the present application; Fig. 9 A schematic diagram of the structure of an edge ring provided in an embodiment of the present application; Fig.10 for Figure 6 A magnified view of the structure of the middle A section; Fig.11 for Figure 7 Enlarged view of the structure of part B in the middle.

[0020] Among them, the reference numerals in the figure are: 10. Grinding pad; 20. Grinding head; 21. First gas flow channel; 211. Main gas flow channel; 212. Sub-gas flow channel; 22. Second gas flow channel; 23. Boss; 30. Pressure diaphragm; 31. Diaphragm body; 32. Protruding ring structure; 321. First diaphragm; 322. Second diaphragm; 323. Third diaphragm; 314. First chamfered corner; 325. Second chamfered corner; 326. Strengthening diaphragm; 33. First pressure chamber; 34. Second pressure chamber; 35. Fourth diaphragm; 351. First sub-diaphragm; 352. Second sub-diaphragm; 36. Third pressure chamber; 37. Fifth diaphragm; 38. Fourth pressure chamber; 40. Target wafer; 50. Rotating seat; 60. Edge ring; 61. Columnar protrusion; 62. Bidirectional flow channel; 70. Rotary joint. DETAILED DESCRIPTION

[0021] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0022] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0023] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present 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.

[0024] 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 the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0025] Please also read Figures 1 to 11 , the grinding mechanism and chemical mechanical grinding equipment provided in the embodiments of the present application are now described.

[0026] To achieve the above objectives, the first aspect of the present application is to provide a grinding mechanism, including a grinding pad 10 and a grinding assembly.

[0027] See also Figures 1 to 3 , wherein the grinding pad 10 is rotatably connected to a preset position and rotates around a first rotation axis to grind the target wafer 40 .

[0028] Specifically, in the application, the grinding pad 10 is disposed on a rotating seat 50 in a chemical mechanical grinding device, the first rotation axis is the rotation axis of the rotating seat 50 , and the rotating seat 50 is driven to rotate by a motor so that the grinding pad 10 grinds the target wafer 40 .

[0029] The grinding assembly is located on a side of the target wafer 40 away from the grinding pad 10 , and includes a grinding head 20 and a pressure diaphragm 30 .

[0030] The pressure diaphragm 30 is connected to the side of the grinding head 20 facing the target wafer 40. The pressure diaphragm 30 is used to transmit the pressure of the gas to the target wafer 40 so that the target wafer 40 and the grinding pad 10 are closely fitted. Under the action of the gas pressure, when the grinding pad 10 rotates around the first rotation axis, it cooperates with the grinding head 20 to grind the target wafer 40.

[0031] The pressure diaphragm 30 includes a diaphragm body 31 and a convex ring structure 32 . The convex ring structure 32 is convexly disposed on one side of the diaphragm body 31 facing the target wafer 40 . The inner diameter of the convex ring structure 32 is greater than or equal to the diameter of the target wafer 40 so that the target wafer 40 can be accommodated in the convex ring structure 32 .

[0032] Along the axial direction of the target wafer 40 , the target wafer 40 is at least partially accommodated in the convex ring structure 32 , so that the side of the target wafer 40 facing away from the grinding pad 10 and at least a portion of the circumferential sidewall of the target wafer 40 are wrapped in the convex ring structure 32 .

[0033] A first annular pressure chamber 33 is provided on the side of the convex ring structure 32 facing away from the grinding pad 10 . The first pressure chamber 33 is used to inject gas. Under the action of the gas pressure in the first pressure chamber 33 , the convex ring structure 32 can fit the edge of the target wafer 40 to the grinding pad 10 .

[0034] When the target wafer 40 is accommodated in the convex ring structure 32, after gas is injected into the first pressure chamber 33, under the action of the pressure in the first pressure chamber 33, the convex ring structure 32 applies pressure to the edge of the target wafer 40 along the direction of the grinding head 20 pointing to the grinding pad 10, thereby fitting the edge of the target wafer 40 onto the grinding pad 10 within a preset pressure range to prevent the target wafer 40 from slipping during the grinding process.

[0035] At the same time, under the action of the pressure in the first pressure chamber 33, the convex ring structure 32 applies pressure to the edge of the target wafer 40 along the direction of the grinding head 20 pointing to the grinding pad 10, so as to prevent the grinding pad 10 from deforming at the edge of the target wafer 40 during the grinding of the target wafer 40, thereby reducing the stress concentration on the target wafer 40 caused by the deformation of the grinding pad 10, so as to prevent the grinding quality of the target wafer 40 from failing to meet the standards.

[0036] Compared with the prior art, the grinding mechanism provided in the present application includes a grinding pad 10 and a grinding assembly, wherein the grinding pad 10 is rotatably connected to a preset position for grinding a target wafer 40, and the grinding assembly is located on the side of the target wafer 40 away from the grinding pad 10, and the grinding assembly includes a grinding head 20 and a pressure diaphragm 30, the grinding head 20 rotates relative to the target wafer 40, and the pressure diaphragm 30 is connected to the grinding head 20; the pressure diaphragm 30 includes a diaphragm body 31 and a convex ring structure 32, the convex ring structure 32 is convexly arranged on the side of the diaphragm body 31 facing the target wafer 40, along the axial direction of the target wafer 40, the target wafer 40 is at least partially accommodated in the convex ring structure 32, and a first pressure chamber 33 is provided on the side of the convex ring structure 32 away from the grinding pad 10, under the action of the gas pressure in the first pressure chamber 33, the convex ring structure 32 makes the edge of the target wafer 40 fit tightly with the grinding pad 10, thereby ensuring the grinding quality of the target wafer 40.

[0037] In one embodiment of the present application, see Figure 1 The grinding head 20 rotates relative to the grinding pad 10 around a second rotation axis, the second rotation axis is the center axis of the grinding head 20, and the first rotation axis and the second rotation axis are parallel and spaced apart.

[0038] In one embodiment of the present application, along the axial direction of the target wafer 40, the circumferential side wall portion of the target wafer 40 is accommodated in the convex ring structure 32, that is, along the axial direction of the target wafer 40, the thickness dimension of the target wafer 40 is greater than the depth dimension of the convex ring structure 32. When the target wafer 40 is located in the convex ring structure 32, the side of the target wafer 40 facing the grinding pad 10 is spaced apart from the side of the convex ring structure 32 facing the grinding pad 10.

[0039] In another embodiment of the present application, along the axial direction of the target wafer 40, the circumferential side walls of the target wafer 40 are all contained in the convex ring structure 32, that is, along the axial direction of the target wafer 40, the thickness dimension of the target wafer 40 is equal to the depth dimension of the convex ring structure 32. When the target wafer 40 is located in the convex ring structure 32, the side of the target wafer 40 facing the grinding pad 10 is flush with the side of the convex ring structure 32 facing the grinding pad 10.

[0040] In the present application, the convex ring structure 32 includes a first diaphragm 321 , a second diaphragm 322 and a third diaphragm 323 .

[0041] See also Figure 3 and Figure 4The first diaphragm 321 extends along the axial direction of the target wafer 40 and is integrally arranged with the diaphragm body 31. The second diaphragm 322 extends along the radial direction of the target wafer 40 and along the direction of the first diaphragm 321 away from the target wafer 40, and is integrally arranged with one end of the first diaphragm 321 away from the diaphragm body 31. The third diaphragm 323 extends along the axial direction of the target wafer 40 and is integrally arranged with one end of the second diaphragm 322 away from the first diaphragm 321. A first pressure chamber 33 is formed between one side of the first diaphragm 321 facing the third diaphragm 323, the side wall of the second diaphragm 322, and the third diaphragm 323 facing the first diaphragm 321.

[0042] In this application, please refer to Figure 4 The connection portion between the second diaphragm 322 and the first diaphragm 321 is provided with a first rounded corner 314, and the connection portion between the third diaphragm 323 and the second diaphragm 322 is provided with a second rounded corner 325. The first rounded corner 314 and the second rounded corner 325 have the same chamfer radius.

[0043] The grinding head 20 drives the target wafer 40 to rotate on the grinding pad 10 through the pressure diaphragm 30. A first chamfer 314 is provided at the connection position between the second diaphragm 322 and the first diaphragm 321, and a second chamfer 325 is provided at the connection position between the third diaphragm 323 and the second diaphragm 322, so that the grinding liquid can pass through the convex ring structure 32 and enter between the target wafer 40 and the grinding pad 10.

[0044] In one embodiment of the present application, see Figure 5 The convex ring structure 32 also includes a reinforcing diaphragm 326 .

[0045] The reinforcement diaphragm 326 is located in the first pressure chamber 33 , and one end of the reinforcement diaphragm 326 is integrally provided with the first diaphragm 321 , and the other end opposite to the one end is integrally provided with the second diaphragm 322 .

[0046] By arranging a reinforcing diaphragm 326 in the first pressure chamber 33, the structural strength of the convex ring is improved.

[0047] In one embodiment of the present application, the reinforcing membrane 326 is an annular structure.

[0048] In another embodiment of the present application, the reinforcement diaphragm 326 is a strip-shaped structure, and there are multiple reinforcement diaphragms 326 , which are evenly spaced along the circumference of the pressure diaphragm 30 .

[0049] In this application, please refer to Figures 2 to 5A plurality of second pressure chambers 34 are provided on the diaphragm body 31, and the plurality of second pressure chambers 34 are arranged in sequence along the radial direction of the target wafer 40, and the plurality of pressure chambers are independent of each other. Among the plurality of second pressure chambers 34, the second pressure chamber 34 located at the center of the diaphragm body 31 is circular, and the remaining second pressure chambers 34 are annular.

[0050] In this application, please refer to Figures 6 to 8 The polishing head 20 is provided with a first gas flow channel 21 inside. The first gas flow channel 21 includes a main gas flow channel 211 and a plurality of sub-gas flow channels 212. The plurality of sub-gas flow channels 212 are all connected to the main gas flow channel 211. Figures 3 to 5 The first pressure chamber 33 and the second pressure chamber 34 are respectively connected to the main gas flow channel 211 through a sub-gas flow channel 212, so as to inject gas into the first pressure chamber 33 and the second pressure chamber 34.

[0051] In the technical solution in which the grinding assembly rotates about the second rotation axis, see Figures 6 to 8 A rotary joint 70 is provided on the grinding head 20 , an air inlet end of the rotary joint 70 is connected to the air source, and an air outlet end of the rotary joint 70 is connected to the first gas flow channel 21 .

[0052] In one embodiment of the present application, the pressure of the gas in the first pressure chamber 33 and each of the multiple second pressure chambers 34 can be adjusted as needed, wherein when the gas pressures in the multiple second pressure chambers 34 are adjusted to different pressure values, different pressures can be applied to different parts of the target wafer 40 to press the target wafer 40 onto the grinding pad 10.

[0053] Pressure sensors are provided at positions on the grinding head 20 corresponding to the first pressure chamber 33 and the multiple second pressure chambers 34, and a micro solenoid valve is provided in each sub-gas flow channel 212. The pressure sensor in each sub-gas flow channel 212 is electrically connected to the corresponding micro solenoid valve. When the pressure in the cavity corresponding to the pressure sensor reaches a preset pressure value, the pressure sensor generates a control signal and transmits the control signal to the micro solenoid valve. The micro solenoid valve closes the corresponding sub-gas flow channel 212 according to the control signal.

[0054] In the present application, the grinding mechanism further includes an edge ring 60 .

[0055] See also Figure 2 , Figure 6 to Figure 7 The edge ring 60 is slidably connected to the grinding head 20 , and the edge ring 60 slides relative to the grinding head 20 along the axial direction of the target wafer 40 . The edge ring 60 is located outside the pressure diaphragm 30 , and the edge ring 60 abuts against the grinding pad 10 .

[0056] In the present application, among the multiple sub-gas flow channels 212, the outlet of one sub-gas flow channel 212 corresponds to the edge ring 60. During the grinding of the target wafer 40, the gas pressure in the sub-gas flow channel 212 is used to make the edge ring 60 fit tightly with the grinding pad 10, so that the grinding ring presses the grinding pad 10 on the outside of the target wafer 40, thereby preventing the deformation of the grinding pad 10 at this position from affecting the grinding of the target wafer 40.

[0057] In another implementation of this application, please refer to Figure 8 A second gas flow channel 22 is provided inside the grinding head 20 , and a gas outlet end of the second gas flow channel 22 corresponds to the edge ring 60 .

[0058] In the technical solution in which the grinding assembly rotates around the second rotation axis, a rotating joint 70 is provided on the grinding head 20, and the rotating joint 70 is provided with two conducting interfaces for simultaneously conducting the first gas flow channel 21 and the second gas flow channel 22, so that the first gas flow channel 21 and the second gas flow channel 22 are connected to the gas source.

[0059] See also Fig. 9 A bidirectional flow channel 62 is provided on one side of the edge ring 60 facing the polishing pad 10 . The bidirectional flow channel 62 is used to flow into the edge of the target wafer 40 or flow out of the target wafer 40 from the edge of the target wafer 40 .

[0060] Specifically, in one embodiment of the present application, a plurality of columnar protrusions 61 are protruded from one side of the edge ring 60 facing the grinding pad 10, wherein the cross-sectional shape of the columnar protrusions 61 is circular, and the plurality of columnar protrusions 61 are evenly spaced along the circumference of the edge ring 60, and a bidirectional flow channel 62 is formed between any two adjacent columnar protrusions 61.

[0061] Compared with the unidirectional and arc-shaped flow channel set on the edge in the prior art, in the edge ring 60, a bidirectional flow channel 62 is formed between any two adjacent columnar protrusions 61, which not only enables the grinding fluid to enter between the target wafer 40 and the grinding pad 10 from the outside of the grinding head 20 through the bidirectional flow channel 62, but also the particulate matter and excess grinding fluid generated after grinding the target wafer 40 and the grinding pad 10 can also flow from the fitting part of the target wafer 40 and the grinding pad 10 to the outside of the grinding head 20 through the bidirectional flow channel 62.

[0062] In one embodiment of the present application, see 3 to Figure 7, a fourth diaphragm 35 is provided on the side of the convex ring structure 32 away from the target wafer 40, and the fourth diaphragm 35 includes a first sub-diaphragm 351 extending radially along the target wafer 40 and a second sub-diaphragm 352 arranged at an angle to the first sub-diaphragm 351, and the first sub-diaphragm 351 and the second sub-diaphragm 352 are arranged integrally. An annular third pressure chamber 36 is formed between the first sub-diaphragm 351, the first sub-diaphragm and the side of the convex ring structure 32 away from the target wafer 40. A boss 23 matching the first sub-diaphragm 351 is provided on the inner side of the grinding head 20 or the edge ring 60, and under the action of the circumferential pressure of the third pressure chamber 36 along the target wafer 40, the first sub-diaphragm 351 fits with the boss 23.

[0063] Specifically, in the present application, the fourth diaphragm 35 is disposed on the side of the third diaphragm 323 away from the first diaphragm 321. And one of the plurality of sub-gas flow channels 212 is connected to the third pressure chamber 36 to facilitate filling the third pressure chamber 36 with gas.

[0064] The boss 23 includes a first side wall extending radially along the target wafer 40, and a second side wall extending axially along the target wafer 40. Under the action of the gas pressure in the third pressure chamber 36, the first sub-diaphragm 351 fits with the first side wall, and the second sub-diaphragm 352 fits with the second side wall, thereby improving the reliability of the connection between the diaphragm body 31 and the grinding head 20.

[0065] In one implementation of this application, see Figure 6 and Fig.10 The boss 23 is arranged on the inner wall of the grinding head 20. After the gas is filled into the third pressure chamber 36, under the pressure of the gas along the axial direction of the target wafer 40, the first side wall of the first sub-diaphragm 351 abuts, and under the pressure of the gas along the radial direction of the target wafer 40, the second side wall of the second sub-diaphragm 352 abuts.

[0066] In another implementation of this application, please refer to Figure 7 and Fig.11 The boss 23 is arranged on the inner side wall of the abutment ring. After the gas is filled into the third pressure chamber 36, under the axial pressure of the gas along the target wafer 40, the first side wall of the first sub-diaphragm 351 abuts, and under the radial pressure of the gas along the target wafer 40, the second side wall of the second sub-diaphragm 352 abuts.

[0067] In one embodiment of the present application, see Figures 3 to 7 A fifth diaphragm 37 is disposed on the side wall of the first pressure chamber 33 away from the target wafer 40 , and an annular fourth pressure chamber 38 is formed between the fifth diaphragm 37 and the side wall of the first pressure chamber 33 away from the target wafer 40 .

[0068] In the technical solution in which the boss 23 is disposed in the grinding head 20 , along the axial direction of the target wafer 40 , part of the fourth pressure chamber 38 corresponds to the grinding head 20 , and another part of the chamber corresponds to the edge ring 60 .

[0069] Specifically, the fifth diaphragm 37 is arranged on the side of the third diaphragm 323 facing the first diaphragm 321, and a fourth pressure chamber 38 is formed between the fifth diaphragm 37 and the side of the third diaphragm 323 facing the first diaphragm 321. Among the multiple sub-airflow channels, one of the sub-airflow channels is connected to the fourth pressure chamber 38. Since part of the cavity of the fourth pressure chamber 38 corresponds to the grinding head 20 along the axial direction of the target wafer 40, and another part of the cavity corresponds to the edge ring 60, after the gas is introduced into the fourth pressure chamber 38, under the action of the pressure of the gas along the horizontal direction of the target wafer 40, the part of the third diaphragm 323 corresponding to the grinding head 20 is attached to the inner wall of the grinding head 20, and the part of the third diaphragm 323 corresponding to the edge ring 60 is attached to the inner wall of the edge ring 60, so as to further improve the connection strength between the pressure diaphragm 30 and the grinding head 20.

[0070] When gas is filled into the first pressure chamber 33 and the second pressure chamber 34, under the action of the radial pressure of the gas in the second pressure chamber 34 along the target diaphragm, the third side wall fits against the inner wall of the edge ring 60, which further improves the reliability of the connection between the pressure diaphragm 30 and the grinding head 20 while preventing the grinding fluid from entering the grinding head 20 and the edge ring 60.

[0071] In a second aspect, the present application provides a chemical mechanical polishing device, including a polishing mechanism, wherein the polishing mechanism is the polishing mechanism provided by any one of the above embodiments.

[0072] Compared with the prior art, the chemical mechanical polishing device provided in the present application includes the polishing mechanism provided by any one of the above items, the polishing mechanism includes a polishing pad 10 and a polishing assembly, wherein the polishing pad 10 is rotatably connected to a preset position for polishing a target wafer 40, the polishing assembly is located on the side of the target wafer 40 away from the polishing pad 10, and includes a polishing head 20 and a pressure diaphragm 30, which rotates relative to the target wafer 40 along the polishing head 20, and the pressure diaphragm 30 is connected to the polishing head 20; the pressure diaphragm 30 includes a diaphragm body 31 and a convex ring structure 32, the convex ring structure 32 is convexly arranged on the side of the diaphragm body 31 facing the target wafer 40, along the axial direction of the target wafer 40, the target wafer 40 is at least partially accommodated in the convex ring structure 32, and a first pressure chamber 33 is provided on the side of the convex ring structure 32 away from the polishing pad 10, under the action of the gas pressure in the first pressure chamber 33, the convex ring structure 32 makes the edge of the target wafer 40 fit tightly with the polishing pad 10, thereby ensuring the polishing quality of the target wafer 40.

[0073] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A grinding mechanism, characterized in that: include: A grinding pad, connected to a preset position and rotating about a preset rotation axis, for grinding a target wafer; A grinding assembly, located on a side of the target wafer away from the grinding pad, comprising a grinding head and a pressure diaphragm; The pressure diaphragm is connected to the grinding head, and the pressure diaphragm includes a diaphragm body and a convex ring structure, wherein the convex ring structure is convexly arranged on a side of the diaphragm body facing the target wafer, and along the axial direction of the target wafer, the target wafer is at least partially accommodated in the convex ring structure; A first pressure chamber is provided on the side of the convex ring structure away from the grinding pad. Under the action of the gas pressure in the first pressure chamber, the convex ring structure can make the edge of the target wafer fit onto the grinding pad.

2. The grinding mechanism according to claim 1, characterized in that: The convex ring structure comprises: A first diaphragm extending along the axial direction of the target wafer and integrally provided with the diaphragm body; A second diaphragm extending in the radial direction of the target wafer and integrally provided with an end of the first diaphragm away from the diaphragm body; A third diaphragm extends along the axial direction of the target wafer and is integrally provided with an end of the second diaphragm away from the first diaphragm; The first pressure chamber is formed between the first diaphragm, the second diaphragm and the third diaphragm.

3. The grinding mechanism according to claim 2, characterized in that: A first rounded corner is provided at a connection portion between the second diaphragm and the first diaphragm; A second rounded corner is provided at a connection position between the third diaphragm and the second diaphragm.

4. The grinding mechanism according to claim 3, characterized in that: The convex ring structure also includes: The reinforcing diaphragm is located in the first pressure chamber, and one end of the reinforcing diaphragm is integrally arranged with the first diaphragm, and the other end opposite to the one end is integrally arranged with the second diaphragm.

5. The grinding mechanism according to claim 4, characterized in that: A plurality of second pressure chambers are disposed on the diaphragm body, and the plurality of second pressure chambers are sequentially arranged along the radial direction of the target wafer, and the plurality of pressure chambers are independent of each other.

6. The grinding mechanism according to claim 1 or 5, characterized in that: Also includes: An edge ring is slidably connected to the grinding head along the circumference of the target wafer and is located outside the pressure diaphragm, and the edge ring abuts against the grinding pad; A bidirectional flow channel is provided on one side of the edge ring facing the grinding pad, and the bidirectional flow channel is used for flowing into the edge of the target wafer or flowing out of the target wafer from the edge of the target wafer.

7. The grinding mechanism according to claim 6, characterized in that: A plurality of columnar protrusions are convexly provided on one side of the edge ring facing the grinding pad, and the plurality of columnar protrusions are evenly spaced along the circumference of the edge ring; The bidirectional flow channel is formed between any two adjacent columnar protrusions.

8. The grinding mechanism according to claim 7, characterized in that: A fourth diaphragm is provided on a side of the convex ring structure away from the target wafer, the fourth diaphragm comprising a first sub-diaphragm extending radially along the target wafer and a second sub-diaphragm arranged at an angle to the first sub-diaphragm, the first sub-diaphragm and the second sub-diaphragm being arranged integrally; A third pressure chamber is formed between the first sub-diaphragm, the first sub-diaphragm and a side of the convex ring structure facing away from the target wafer; A boss matched with the first sub-diaphragm is provided on the inner side of the grinding head or the edge ring, and under the action of the pressure of the third pressure chamber along the circumference of the target wafer, the first sub-diaphragm fits with the boss.

9. The grinding mechanism according to claim 8, characterized in that: A fifth diaphragm is disposed on the side wall of the first pressure chamber away from the target wafer, and a fourth pressure chamber is formed between the fifth diaphragm and the side wall of the first pressure chamber away from the target wafer.

10. A chemical mechanical polishing device, characterized in that: include: A grinding mechanism, wherein the grinding mechanism is the grinding mechanism described in any one of claims 1-9.

Images