Retainer for wafer polishing and wafer polishing device

Abstract

The utility model discloses a retainer used for wafer polishing and a wafer polishing device, the retainer used for wafer polishing comprises a first connecting disc, the upper end of which is provided with a connecting structure; the retaining ring is connected with the lower end of the first connecting disc and is used for limiting the wafer; the multiple clamping assemblies are arranged on the retaining ring and arranged in the circumferential direction of the retaining ring, each clamping assembly comprises an upper clamping piece, a lower clamping piece and a first driving piece, and the upper clamping pieces and the lower clamping pieces are oppositely arranged in the axial direction of the retaining ring; the upper clamping piece and the lower clamping piece are respectively provided with an upper clamping part and a lower clamping part, and the upper clamping part and the lower clamping part extend out of the inner wall in the retaining ring; the first driving piece is connected with the upper clamping piece and / or the lower clamping piece. According to the retainer for wafer polishing, the material utilization rate is increased, the service life is prolonged, and the capability of adapting to wafers with different thicknesses is enhanced.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of semiconductor manufacturing, in particular to a kind of retainer and wafer polishing device for wafer polishing. BACKGROUND

[0002] As shown in Figure 1 The wafer polishing device in the prior art includes a polishing head 1a, a retainer 1b and a back film 1c. The polishing head 1a is connected to the retainer 1b by a buckle, and the back film is located inside the retainer 1b and is fixed integrally with the retainer 1b. During polishing, the wafer is placed in the retainer 1b, and the back film 1c contacts and presses the wafer surface, thereby stably pressing the wafer on the polishing pad, while the retainer 1b maintains contact with the polishing pad.

[0003] However, the integrated back film and retainer structure used in the prior art has the following problems: first, when the back film is worn out due to use or aging, the entire retainer must be scrapped, which leads to unnecessary material waste. Since the service life of the back film is relatively short and needs to be replaced regularly, while the other parts of the retainer usually have a longer service life, after the back film is worn out, the other parts of the retainer can still be used, and the overall scrapping causes waste of resources. Second, the retainer back film of the existing integrated structure can only adapt to wafers of a certain thickness. For wafers of different thicknesses, different specifications of retainers must be replaced, which not only increases the complexity in production and use, but also leads to additional consumption of equipment and materials, thereby reducing production efficiency and cost effectiveness. SUMMARY

[0004] Therefore, it is necessary to provide a retainer and wafer polishing device for wafer polishing to improve material utilization, extend service life, and enhance the ability to adapt to wafers of different thicknesses, in view of the defects of the existing integrated retainer in terms of material waste, mismatched service life and adaptability.

[0005] A retainer for wafer polishing, comprising:

[0006] A first connecting disc, having a connecting structure at its upper end for detachable connection with a polishing head;

[0007] A retaining ring connected to the lower end of the first connecting disc for limiting the wafer;

[0008] A plurality of clamping assemblies are arranged on the holding ring and along the circumferential direction of the holding ring, and the clamping assembly comprises an upper clamping piece, a lower clamping piece and a first driving piece, wherein the upper clamping piece and the lower clamping piece are arranged oppositely along the axial direction of the holding ring, and the upper clamping piece and the lower clamping piece are respectively provided with an upper clamping part and a lower clamping part which protrude from the inner wall of the holding ring; the first driving piece is connected with the upper clamping piece and / or the lower clamping piece, and is used for moving the upper clamping piece and the lower clamping piece in opposite directions or opposite directions, so that the upper clamping part and the lower clamping part clamp or release the back film.

[0009] In one of the embodiments, the upper clamping part can move in the radial direction of the holding ring, and the upper clamping piece further comprises a second driving piece connected with the upper clamping part, which is used for driving the upper clamping part to move in the radial direction of the holding ring.

[0010] In one of the embodiments, the second driving piece is a pneumatic cylinder.

[0011] In one of the embodiments, the lower clamping part can move in the radial direction of the holding ring, and the lower clamping piece further comprises a third driving piece connected with the lower clamping part, which is used for driving the lower clamping part to move in the radial direction of the holding ring.

[0012] In one of the embodiments, the third driving piece is a pneumatic cylinder.

[0013] In one of the embodiments, the first driving piece is a pneumatic cylinder.

[0014] In one of the embodiments, the connecting structure comprises a plurality of clamping grooves arranged on the upper surface of the first connecting disc.

[0015] In one of the embodiments, the first connecting disc is provided with a first pipe interface on the upper surface.

[0016] A wafer polishing device, comprising:

[0017] A polishing head comprising a second connecting disc;

[0018] The holding device for wafer polishing, the first connecting disc of the holding device is connected with the second connecting disc of the polishing head.

[0019] A back film is located in the holding ring and is fixed in the holding ring by a plurality of clamping assemblies, and the holding device and the back film form a wafer containing space.

[0020] The back film of the above-mentioned holder for wafer polishing adopts a detachable design, and the back film can be replaced independently without scrapping the whole holder. This not only greatly reduces the waste of resources caused by back film loss, but also reduces maintenance costs and improves the long-term economic benefits of the equipment. Compared with the existing integrated back film structure, the other parts of the holder can continue to be used after the back film is lost, thereby improving the overall service life. Moreover, the upper clamping member and the lower clamping member can move axially along the holding ring, thereby the thickness of the accommodated wafer can be adjusted, so that the holder can adapt to wafers of different thicknesses. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of an existing wafer polishing device;

[0022] Figure 2 It is a structural schematic diagram of a wafer polishing device in one of the embodiments of the present application, and shows the state when the polishing head and the holder are separated;

[0023] Figure 3 It is a structural schematic diagram of a wafer polishing device in one of the embodiments of the present application, and shows the state when the polishing head and the holder are combined;

[0024] Figure 4 It is a structural schematic diagram of the upper clamping member in one of the embodiments of the present application, and shows the state when the upper clamping part is retracted;

[0025] Figure 5 It is a structural schematic diagram of the upper clamping member in one of the embodiments of the present application, and shows the state when the upper clamping part is extended;

[0026] Figure 6 It is a structural schematic diagram of the lower clamping member in one of the embodiments of the present application, and shows the state when the lower clamping part is retracted;

[0027] Figure 7 It is a structural schematic diagram of the lower clamping member in one of the embodiments of the present application, and shows the state when the lower clamping part is extended.

[0028] Explanation of reference signs: 1, holder; 11, first connecting disc; 111, clamping groove; 112, first pipeline interface; 12, holding ring; 13, upper clamping member; 131, upper clamping part; 132, second driving member; 14, lower clamping member; 141, lower clamping part; 142, third driving member; 15, first driving member; 2, back film; 3, polishing head; 31, rotating shaft; 32, second connecting disc; 321, buckle; 322, second pipeline interface; 4, wafer. DETAILED DESCRIPTION

[0029] In order to make the above objects, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings. Obviously, the following detailed description of the specific embodiments is only a part of the embodiments of the present application, and the present application can also be implemented in many other embodiments different from those described herein. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0030] In this document, when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present. The terms "front," "back," "upper," "lower," and the like, are used herein for ease of description and are not intended to limit the scope of the present application.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application.

[0032] In order to facilitate the understanding of the wafer polishing device provided by the embodiments of the present application, the application scenario of the wafer polishing device provided by the embodiments of the present application will be described first. The wafer polishing device is applied to a process of polishing the surface of a wafer by using a chemical mechanical polishing (CMP) method, and is used to hold the wafer on a polishing platform. The wafer polishing device will be described in detail below with reference to the drawings.

[0033] As shown in Figure 2 , 3 In one of the embodiments of the present application, a holder 1 for wafer polishing is provided, which comprises a first connecting disc 11, a retaining ring 12 and a plurality of clamping assemblies. The first connecting disc 11 has a first surface (i.e. an upper surface) and a second surface (i.e. a lower surface), and the first surface of the first connecting disc 11 is provided with a connecting structure which is detachably connected with a polishing head 3. In one embodiment, the connecting structure comprises a plurality of clamping grooves 111 provided on the first surface of the first connecting disc 11. A plurality of buckles 321 are correspondingly provided on the polishing head 3, and the first connecting disc 11 is detachably connected with the polishing head 3 through the cooperation of the buckles and the clamping grooves. In order to facilitate operation and installation, the shape of the first connecting disc 11 is preferably circular.

[0034] The retaining ring 12 is annular in structure and is fixed to the second surface of the first connecting plate 11 or is integrated with the first connecting plate 11. The retaining ring 12 is a ring body structure commonly used in the prior art for limiting the wafer in the process of chemical mechanical polishing to lock the wafer 4 in it. The retaining ring 12 has a space for accommodating the wafer. When the wafer polishing device approaches the polishing pad on the polishing platform, the polishing pad, the first connecting plate 11 and the retaining ring 12 together fix the wafer 4 in the internal space to prevent the wafer from falling out.

[0035] A plurality of clamping assemblies are arranged on the retaining ring 12 along the circumferential direction of the retaining ring, and the clamping assemblies comprise an upper clamping piece 13, a lower clamping piece 14 and a first driving piece 15. The upper clamping piece 13 and the lower clamping piece 14 are arranged opposite to each other along the axial direction of the retaining ring, and the upper clamping piece 13 and the lower clamping piece 14 are respectively provided with an upper clamping portion 131 and a lower clamping portion 141 which extend out of the inner wall of the retaining ring. The first driving piece 15 is connected with the upper clamping piece 13 and / or the lower clamping piece 14, and is used for moving the upper clamping piece 13 and the lower clamping piece 14 in opposite directions or in opposite directions, so as to clamp or release the back film 2 by the upper clamping portion 131 and the lower clamping portion 141.

[0036] The retaining ring 1 for wafer polishing adopts a detachable back film design, and the back film 2 can be replaced independently without scrapping the entire retaining ring. This not only greatly reduces the waste of resources caused by the loss of the back film, but also reduces the maintenance cost and improves the long-term economic benefit of the equipment. Compared with the existing integrated back film structure, the retaining ring of the utility model can continue to be used after the back film is lost, thereby improving the overall service life. Moreover, the upper clamping piece 13 and the lower clamping piece 14 can move along the axial direction of the retaining ring, so that the thickness of the wafer accommodating space can be adjusted, and the retaining ring can adapt to wafers of different thicknesses.

[0037] As Figure 4 , 5As shown in the figure, in one embodiment, the upper clamping part 131 can move in the radial direction of the holding ring, the upper clamping part 131 further comprises a second driving part 132, the second driving part 132 is connected with the upper clamping part 131, and is used for driving the upper clamping part 131 to move in the radial direction of the holding ring. In this way, when the back film 2 is installed or dismounted, the second driving part 132 drives the upper clamping part 131 to retract, and the back film 2 can be smoothly installed in the holding ring 12 or taken out of the holding ring 12. The second driving part 132 is preferably a pneumatic cylinder, the piston rod of the pneumatic cylinder is connected with the upper clamping part 131, and the air inlet and the air outlet of the pneumatic cylinder are connected with the first pipeline interface 112 arranged on the upper surface of the first connecting disc 11 through air pipes. The pneumatic pressure adjusting system of the pneumatic cylinder controls the piston rod of the pneumatic cylinder to retract in a predetermined range, and drives the upper clamping part 131 to move in the radial direction of the holding ring 12. In addition to the pneumatic cylinder, the second driving part 132 can also adopt a driving mode such as an electric motor.

[0038] As shown in the figure, Figure 6 , 7 As shown in the figure, in one embodiment, the lower clamping part 141 can move in the radial direction of the holding ring, the lower clamping part 141 further comprises a third driving part 142, the third driving part 142 is connected with the lower clamping part 141, and is used for driving the lower clamping part 141 to move in the radial direction of the holding ring. In this way, when the back film 2 is installed or dismounted, the third driving part 142 drives the lower clamping part 141 to retract, and the back film 2 can be smoothly installed in the holding ring 12 or taken out of the holding ring 12. The third driving part 142 is preferably a pneumatic cylinder, the piston rod of the pneumatic cylinder is connected with the lower clamping part 141, and the air inlet and the air outlet of the pneumatic cylinder are connected with the first pipeline interface 112 arranged on the upper surface of the first connecting disc 11 through air pipes. The pneumatic pressure adjusting system of the pneumatic cylinder controls the piston rod of the pneumatic cylinder to retract in a predetermined range, and drives the lower clamping part 141 to move in the radial direction of the holding ring 12. In addition to the pneumatic cylinder, the third driving part 142 can also adopt a driving mode such as an electric motor.

[0039] The first driving part 15 can be selected from a pneumatic cylinder, an electric motor or a stepping motor, etc. Preferably, the first driving part 15 is a pneumatic cylinder, the air inlet and the air outlet of the pneumatic cylinder are connected with the first pipeline interface 112 arranged on the upper surface of the first connecting disc 11 through air pipes. The first driving part 15 can adopt two independent pneumatic cylinders, which respectively drive the upper clamping part 13 and the lower clamping part 14. A pneumatic cylinder can also be adopted, the piston rod of the pneumatic cylinder is connected with the upper clamping part 13 and the lower clamping part 14 through a transmission mechanism, and the synchronous movement of the upper clamping part 13 and the lower clamping part 14 in the opposite directions is realized.

[0040] Wafer polishing device

[0041] In another embodiment of the present application, a wafer polishing device is provided, comprising a polishing head 3, a holder 1 and a back film 2. The polishing head 3 comprises a rotating shaft 31 and a second connecting disc 32, the rotating shaft 31 is arranged on the upper surface of the second connecting disc 32, and the lower surface of the second connecting disc 32 is provided with a buckle 321 and a second pipeline interface 322, the buckle 321 is matched with the clamping groove 111 on the first connecting disc 11, and the second pipeline interface 322 is matched with the first pipeline interface 112 on the first connecting disc 11.

[0042] The holder is the same as the holder in the above embodiment, and will not be described here.

[0043] The back film 2 is located in the holding ring 12 and is fixed in the holding ring 12 through a plurality of clamping assemblies, and the holder 1 and the back film 2 form a wafer containing space 4.

[0044] Through the above structure design and implementation, the wafer polishing device of the present application not only realizes the detachable design of the back film 2, reduces the equipment maintenance cost and resource waste, but also accurately adjusts the driving mode of the clamping assembly, so that the wafer 4 can be stably maintained on the polishing platform, thereby ensuring the stability and consistency of the polishing process.

[0045] The above embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the present application. It should be pointed out that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which belong to the protection scope of the present application.

Claims

1. A retainer for wafer polishing, characterized by, The utility model relates to a wafer polishing holder, comprising: a first connecting plate, an upper end of which is provided with a connecting structure detachably connected with a polishing head; a retaining ring connected with a lower end of the first connecting plate for limiting a wafer; a plurality of clamping assemblies arranged on the retaining ring along a circumferential direction of the retaining ring, the clamping assemblies comprising: an upper clamping piece, a lower clamping piece, and a first driving piece, wherein the upper clamping piece and the lower clamping piece are oppositely arranged along an axial direction of the retaining ring, and the upper clamping piece and the lower clamping piece are respectively provided with an upper clamping portion and a lower clamping portion, the upper clamping portion and the lower clamping portion extending out of an inner wall in the retaining ring; the first driving piece is connected with the upper clamping piece and / or the lower clamping piece for moving the upper clamping piece and the lower clamping piece in opposite directions or opposite directions, so that the upper clamping portion and the lower clamping portion clamp or release a back film.

2. The holder for wafer polishing according to claim 1, wherein The upper clamping portion can move in an extension and retraction direction along a radius direction of the retaining ring, and the upper clamping piece further comprises a second driving piece connected with the upper clamping portion for driving the upper clamping portion to move in an extension and retraction direction along the radius direction of the retaining ring.

3. The holder for wafer polishing according to claim 2, wherein, The second driving piece is a pneumatic cylinder.

4. The holder for wafer polishing according to claim 1, wherein The lower clamping portion can move in an extension and retraction direction along a radius direction of the retaining ring, and the lower clamping piece further comprises a third driving piece connected with the lower clamping portion for driving the lower clamping portion to move in an extension and retraction direction along the radius direction of the retaining ring.

5. The holder for wafer polishing according to claim 4, wherein The third driving piece is a pneumatic cylinder.

6. The holder for wafer polishing according to claim 1, wherein The first driving piece is a pneumatic cylinder.

7. The holder for wafer polishing according to claim 1, wherein The connecting structure comprises a plurality of clamping grooves arranged on an upper surface of the first connecting plate.

8. The holder for wafer polishing according to claim 1, wherein The first connecting plate is provided with a first pipeline interface on the upper surface.

9. A wafer polishing apparatus characterized by comprising: The utility model relates to a wafer polishing holder, comprising: a polishing head comprising a second connecting plate; the wafer polishing holder according to any one of claims 1 to 8, a first connecting plate of the holder is connected with a second connecting plate of the polishing head; a back film located in the retaining ring and fixed in the retaining ring by a plurality of clamping assemblies, and the holder and the back film form a wafer containing space.

Images