Grinding head, grinding equipment and grinding method

Abstract

The embodiment of the invention provides a grinding head, grinding equipment and a grinding method, and the grinding head comprises a grinding head support; the first grinding sleeve is borne in the grinding head support, the first grinding sleeve comprises a base film, the base film is suitable for being elastically deformed in the axial direction of the first grinding sleeve, and when the first grinding sleeve is used for grinding, the front face of the base film makes contact with a wafer to be ground; the one or more upright inverted-T-shaped annular air bags are located in the base film and abut against the back face of the base film; the one or more inverted T-shaped annular air bags are located in the base film and abut against the back face of the base film; wherein the upright inverted-T-shaped annular air bags and the inverted inverted-T-shaped annular air bags are alternately arranged on the base film at intervals, and the side walls of the adjacent upright inverted-T-shaped annular air bags and the inverted inverted-T-shaped annular air bags abut against each other. By adopting the grinding head provided by the embodiment of the invention, the wafer grinding yield can be improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and in particular to a grinding head, a grinding device and a grinding method. Background Art

[0002] In the semiconductor process flow, Chemical Mechanical Planarization (CMP) is a very important process, sometimes also called Chemical Mechanical Polishing (CMP). The so-called chemical mechanical polishing is a process that uses a grinding head with a combination of chemical and mechanical effects to remove excess material from the wafer and make the wafer obtain a flat surface. Specifically, this polishing method usually clamps the wafer to be polished and presses it on a high-speed rotating grinding pad with a certain pressure. Under the action of multiple components such as polishing agents, corrosive agents and grinding liquids, the wafer and the grinding pad rub against each other to achieve the purpose of flattening.

[0003] However, the existing grinding head has the problem of reduced grinding yield during the actual grinding process. Therefore, how to provide a technical solution to grind the wafer to improve the wafer grinding yield has become a technical problem that technicians in this field need to solve urgently. Summary of the invention

[0004] The technical problem solved by the present invention is to improve the wafer grinding yield by providing a grinding head, a grinding device and a grinding method.

[0005] In order to solve the above problems, an embodiment of the present invention provides a grinding head, including: a grinding head bracket; a first grinding sleeve, carried in the grinding head bracket, the first grinding sleeve including: a base film, suitable for elastic deformation along the axial direction of the first grinding sleeve, when grinding by the first grinding sleeve, the front side of the base film contacts the wafer to be ground; one or more upright convex-shaped annular air bags, located in the base film and in conflict with the back side of the base film; one or more inverted convex-shaped annular air bags, located in the base film and in conflict with the back side of the base film; wherein the plurality of upright convex-shaped annular air bags and the plurality of inverted convex-shaped annular air bags are alternately arranged on the base film, and the side walls of adjacent upright convex-shaped annular air bags and inverted convex-shaped annular air bags are in conflict with each other.

[0006] Optionally, the grinding head bracket includes:

[0007] a tubular peripheral support;

[0008] A spacer connected to the inner wall of the tubular peripheral support, wherein the spacer and the peripheral support are in an H shape in a cross section perpendicular to the surface of the basement membrane;

[0009] Wherein, the first grinding sleeve is carried on the first surface of the spacer in the grinding head bracket.

[0010] Optionally, the grinding head further comprises:

[0011] The second grinding sleeve is carried on the second surface of the spacer in the grinding head bracket, and the second grinding sleeve includes:

[0012] An auxiliary film, adapted to be elastically deformed along the axial direction of the second grinding sleeve, wherein the front surface of the auxiliary film contacts the wafer during grinding by the second grinding sleeve;

[0013] A plurality of fan-shaped air bags are located in the auxiliary film and are in conflict with the back surface of the auxiliary film. The centers of the fan-shaped air bags are consistent, and the side walls of adjacent fan-shaped air bags are in conflict with each other.

[0014] Optionally, the grinding head further comprises: a limiting structure located on the second surface of the spacer or on the back surface of the auxiliary film;

[0015] Wherein, adjacent limiting structures are used to limit the fan-shaped airbags therebetween.

[0016] Optionally, the limiting structure is provided with a third air hole, and the auxiliary membrane has a fourth air hole adapted to the third air hole.

[0017] Optionally, the material of the base film includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane, the material constituting the upright convex-shaped annular airbag includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane, and the material constituting the side wall of the inverted convex-shaped annular airbag includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane;

[0018] The material of the auxiliary membrane includes one or more of fluorinated rubber, vulcanized rubber and polyurethane, and the material constituting the fan-shaped airbag includes one or more of fluorinated rubber, vulcanized rubber and polyurethane.

[0019] Optionally, the shape of the cross section of the upright convex-shaped annular airbag along the direction perpendicular to the wafer surface includes: a convex shape, and the shape of the cross section of the inverted convex-shaped annular airbag along the direction parallel to the wafer surface includes: an inverted convex shape;

[0020] The shape of the base film includes: one or more of a circular cylinder, an elliptical cylinder, and a square cylinder;

[0021] The shape of the auxiliary film includes: one or more of a circular cylinder, an elliptical cylinder, and a square cylinder;

[0022] The shape of the spacer includes one or more of a circular cylinder, an elliptical cylinder, and a square cylinder.

[0023] Optionally, the cross-sectional area of ​​the tubular peripheral support in a direction parallel to the wafer surface is greater than or equal to the area of ​​the base film, and the area of ​​the base film is greater than or equal to the area of ​​the wafer;

[0024] The cross-sectional area of ​​the tubular peripheral support in a direction parallel to the wafer surface is greater than or equal to the area of ​​the auxiliary film, and the area of ​​the auxiliary film is greater than or equal to the area of ​​the wafer.

[0025] Optionally, the grinding head further comprises:

[0026] Pairs of limiting protrusions, wherein a first limiting protrusion in each pair of limiting protrusions is located on the first surface of the spacer, and a second limiting protrusion is located on the back surface of the base film;

[0027] Among them, two adjacent pairs of limiting protrusions are used to limit the upright convex-shaped annular airbag or the inverted convex-shaped annular airbag therebetween.

[0028] Optionally, the pair of limiting protrusions are provided with first pores, and the base film has second pores adapted to the first pores.

[0029] Optionally, the grinding head further includes:

[0030] adjacent first redundant airbag and second redundant airbag;

[0031] Wherein, the first redundant airbag is located in the basement membrane and conflicts with the back side of the basement membrane and a part of the inner wall of the tubular peripheral support;

[0032] The second redundant airbag is located in the basement membrane and contacts the first surface of the spacer and a portion of the inner wall of the tubular peripheral support.

[0033] Optionally, the cross-sectional shape of the first redundant airbag along the direction perpendicular to the wafer surface includes one or more of square, circle, and triangle, and the cross-sectional shape of the second redundant airbag along the direction perpendicular to the wafer surface includes one or more of square, circle, and triangle.

[0034] A grinding device, applied to the aforementioned grinding head, comprises: a control system;

[0035] The control system controls the first grinding sleeve to adsorb the wafer through the first air hole and the second air hole;

[0036] The control system controls the second grinding sleeve to adsorb the wafer through the third air hole and the fourth air hole;

[0037] The control system independently controls each upright convex-shaped annular airbag, each inverted convex-shaped annular airbag, each fan-shaped airbag, the first redundant airbag and the second redundant airbag to expand and contract in a direction perpendicular to the wafer surface.

[0038] Accordingly, an embodiment of the present invention further provides a grinding method, which is applied to a grinding head, wherein the grinding head includes a first grinding sleeve and / or a second grinding sleeve:

[0039] The grinding method comprises:

[0040] Providing a wafer, wherein a film layer to be polished is provided on a first surface of the wafer;

[0041] The film thickness of the film layer to be ground is obtained, and according to the distribution of the film thickness, it is determined whether to select the first grinding sleeve or the second grinding sleeve to grind the film layer to be ground.

[0042] Optionally, in response to selecting the first grinding sleeve to grind the film layer to be ground, the grinding method further includes:

[0043] Determining grinding parameters of the first grinding sleeve, wherein the grinding parameters include: grinding pressure and grinding time;

[0044] The second surface opposite to the first surface of the wafer is fixed on the base film of the first grinding sleeve for grinding.

[0045] Optionally, in response to selecting the second grinding sleeve to grind the film layer to be ground, the grinding method further includes:

[0046] Determining grinding parameters of the second grinding sleeve, wherein the grinding parameters include: grinding pressure and grinding time;

[0047] The second surface opposite to the first surface of the wafer is fixed on the base film of the second grinding sleeve for grinding.

[0048] Compared with the prior art, the technical solution of the embodiment of the present invention has the following advantages:

[0049] A grinding head according to an embodiment of the present invention comprises: a first grinding sleeve; the first grinding sleeve comprises: a base film, one or more upright convex-shaped annular airbags, and one or more inverted convex-shaped annular airbags, wherein the plurality of upright convex-shaped annular airbags and the plurality of inverted convex-shaped annular airbags are alternately arranged on the base film, and the side walls of adjacent upright convex-shaped annular airbags and inverted convex-shaped annular airbags are in conflict with each other. Each upright convex-shaped annular airbag and each inverted convex-shaped annular airbag respectively correspond to different film thickness distributions on the wafer, and according to different film thicknesses, the deformation amount of elastic deformation of the base film along the axial direction of the first grinding sleeve is adjusted through the upright convex-shaped annular airbag and / or the inverted convex-shaped annular airbag, so that different film thickness partitions are subjected to grinding pressures adapted to the film thicknesses, thereby improving the wafer grinding yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, 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 embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0051] Figure 1 to Figure 2 It is a schematic diagram of the structure of a grinding head;

[0052] Figures 3 to 12 is a schematic structural diagram of a grinding head according to an embodiment of the present invention;

[0053] Fig.13 It is a schematic flow chart of a grinding method corresponding to the grinding head according to an embodiment of the present invention. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions 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. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0055] As can be seen from the background technology, a grinding head has the problem of reduced wafer grinding yield. Figure 1 to Figure 2 A grinding head is shown, and the reasons for the reduction of wafer grinding yield are analyzed.

[0056] refer to Figure 1 and Figure 2 ,in Figure 2 for Figure 1The grinding head comprises: a grinding frame 100 and a grinding sleeve 101; the grinding sleeve 101 is arranged on the grinding frame 100. During grinding, the first surface 102 of the grinding sleeve 101 contacts the wafer, and the wafer is ground by adjusting the pressure applied to the wafer by the grinding sleeve 101.

[0057] The use of the above-mentioned grinding head has the following problems: In the actual grinding process, the film layers of different thicknesses on the wafer are all ground with uniform grinding pressure and grinding time. After grinding, some areas of the film layer on the wafer are over-ground, while some areas are not ground, resulting in the scrapping of the wafer and reducing the wafer grinding yield;

[0058] In view of the above technical problems, an embodiment of the present invention provides a grinding head to improve the wafer grinding yield.

[0059] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0060] refer to Figures 3 to 12 Schematic diagram of the structure of the grinding head according to the embodiment of the present invention.

[0061] The grinding head of the embodiment of the present invention comprises: a grinding head bracket; a first grinding sleeve, which is carried in the grinding head bracket, and the first grinding sleeve comprises: a spacer, which is suitable for elastic deformation along the axial direction of the first grinding sleeve, and when grinding by the first grinding sleeve, the front side of the spacer contacts the wafer to be ground; one or more upright convex-shaped annular air bags, which are located in the spacer and conflict with the back side of the spacer; one or more inverted convex-shaped annular air bags, which are located in the spacer and conflict with the back side of the spacer; wherein the plurality of upright convex-shaped annular air bags and the plurality of inverted convex-shaped annular air bags are alternately arranged on the spacer, and the side walls of adjacent upright convex-shaped annular air bags and inverted convex-shaped annular air bags conflict with each other.

[0062] The grinding head of the embodiment of the present invention comprises: a first grinding sleeve; the first grinding sleeve comprises: a spacer, one or more upright convex-shaped annular airbags, and one or more inverted convex-shaped annular airbags, wherein the plurality of upright convex-shaped annular airbags and the plurality of inverted convex-shaped annular airbags are alternately arranged on the spacer, and the side walls of adjacent upright convex-shaped annular airbags and inverted convex-shaped annular airbags are in conflict with each other. Each upright convex-shaped annular airbag and each inverted convex-shaped annular airbag respectively correspond to different film thickness distributions on the wafer, and according to different film thicknesses, the deformation amount of the elastic deformation of the spacer along the axial direction of the first grinding sleeve is adjusted through the upright convex-shaped annular airbag and / or the inverted convex-shaped annular airbag, so that different film thickness partitions are subjected to grinding pressures adapted to the film thickness, thereby improving the wafer grinding yield.

[0063] refer to Figure 3 and Figure 4 ,in, Figure 4 yes Figure 3 The cross-sectional view along the middle line B1B2. The grinding head comprises: a grinding head bracket.

[0064] The grinding bracket is used for carrying the first grinding sleeve and the second grinding sleeve to drive the first grinding sleeve and the second grinding sleeve to grind the wafer.

[0065] The grinding head support includes: a tubular peripheral support 200 .

[0066] The material of the tubular peripheral bracket 200 includes: metal material (such as stainless steel, aluminum, etc.) or anti-static plastic material (such as polycarbonate, electro-polypropylene, acrylic, etc.); the tubular peripheral bracket 200 is an annular column structure, and the annular column structure includes any of the following: a circular annular column structure, an elliptical annular column structure, a square annular column structure, etc. The embodiment of the present application does not limit the tubular material and the specific column structure, and those skilled in the art can adjust the settings according to actual conditions. In this embodiment, the material of the tubular peripheral bracket 200 is metal, and the tubular peripheral bracket 200 is a circular annular column structure.

[0067] The grinding head support includes: a spacer 201 connected to the inner wall 202 of the tubular peripheral support 200, and used for carrying and separating the first grinding sleeve and the second grinding sleeve.

[0068] The spacer 201 includes a first surface 203 and a second surface 204 .

[0069] The spacer 201 may be shaped like one or more of a circular annular cylinder, an elliptical annular cylinder, and a square annular cylinder. In this embodiment, the spacer 201 is shaped like a circular annular cylinder.

[0070] The material of the spacer 201 includes: metal material (such as stainless steel material, aluminum material, etc.) or anti-static plastic material (such as polycarbonate, polypropylene, acrylic, etc.). In this embodiment, the material of the spacer 201 is metal material.

[0071] In a cross section perpendicular to the surface of the base film 301 , the spacer 201 and the peripheral support are in an H shape; wherein the first grinding sleeve is supported on the first surface 203 of the spacer 201 in the grinding head support.

[0072] The spacer 201 and the peripheral support are H-shaped, which can keep the surfaces of the base film of the first grinding sleeve and the auxiliary film of the second grinding sleeve parallel to the wafer surface, so that the grinding pressure of the grinding head on the wafer is within a preset error.

[0073] refer to Figures 5 to 7 ,in, Figure 5 is a top view of the first grinding sleeve 300 located on the tubular peripheral support 200; Figure 6 for Figure 5 The cross-section along C1C2, Figure 7 for Figure 5 The cross-sectional view along the middle line D1D2. The grinding head comprises: a first grinding sleeve 300, which is carried in the grinding head bracket. The first grinding sleeve is used for grinding wafers.

[0074] It should be noted that, in order to clearly and concisely present the cross-sectional view of the first grinding sleeve, Figure 6 The spacer 201 is not shown in the figure, but this should not be construed as a limitation of the present invention.

[0075] The first grinding sleeve includes: a base film 301 .

[0076] The basement membrane 301 provides a supporting foundation for the one or more upright convex-shaped annular airbags and the one or more inverted convex-shaped annular airbags.

[0077] The base film 301 is suitable for elastic deformation along the axial direction of the first grinding sleeve. When grinding with the first grinding sleeve, the front side 301a of the base film 301 contacts the wafer to be ground, that is, the base film 301 is elastically deformed in a direction perpendicular to the surface of the wafer, and the base film 301 can be close to and away from the wafer; when grinding with the first grinding sleeve, the front side 301a of the base film 301 contacts the back side of the wafer to be ground.

[0078] The back side of the wafer is the side without the semiconductor device film layer.

[0079] The material of the base film 301 includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane. In this embodiment, the material of the base film 301 is fluorinated rubber.

[0080] The shape of the base film 301 includes one or more of a circular cylinder, an elliptical cylinder, and a square cylinder. In this embodiment, the shape of the base film 301 is a circular cylinder.

[0081] The first grinding sleeve includes: one or more upright convex-shaped annular air bags, which are located in the base film 301 and contact the back of the base film 301. It has the following beneficial effects: according to different film thickness distribution areas on the wafer, each upright convex-shaped annular air bag can independently provide grinding pressure adapted to the film thickness distribution area to grind the front side of the wafer, thereby improving the wafer grinding yield.

[0082] The front side of the wafer is the side covered with the semiconductor device film layer.

[0083] The one or more upright convex-shaped annular airbags are located inside the basement membrane 301, that is, the area of ​​the one or more upright convex-shaped annular airbags is smaller than the area of ​​the basement membrane 301; the one or more upright convex-shaped annular airbags are in contact with the back side of the basement membrane 301, that is, the one or more upright convex-shaped annular airbags are in seamless contact with the basement membrane 301.

[0084] In this embodiment, the number of the upright convex-shaped annular airbags is two, namely a first upright convex-shaped annular airbag 302 and a second upright convex-shaped annular airbag 303 .

[0085] The first upright convex-shaped annular airbag 302 and the second upright convex-shaped annular airbag 303 are respectively located in the basement membrane 301 and are in seamless contact with the basement membrane 301, that is, one end 302a of the first upright convex-shaped annular airbag 302 and one end 303a of the second upright convex-shaped annular airbag 303 are respectively in seamless contact with the basement membrane 301.

[0086] The shape of the upright convex-shaped annular airbag in the cross section along the direction perpendicular to the wafer surface includes: a convex shape.

[0087] The material constituting the upright convex-shaped annular airbag includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane. In this embodiment, the material constituting the upright convex-shaped annular airbag is fluorinated rubber.

[0088] The first grinding sleeve includes: one or more inverted convex-shaped annular air bags, which are located in the base film 301 and are in conflict with the back side of the base film 301. The following beneficial effects are achieved: according to different film thickness distribution areas on the wafer, each inverted convex-shaped annular air bag can independently provide a grinding pressure adapted to the film thickness distribution area to grind the front side of the wafer, thereby improving the wafer grinding yield.

[0089] The one or more inverted convex-shaped annular airbags are located inside the basement membrane 301, that is, the area of ​​the one or more inverted convex-shaped annular airbags is smaller than the area of ​​the basement membrane 301; the one or more inverted convex-shaped annular airbags are in conflict with the back side of the basement membrane 301, that is, the one or more inverted convex-shaped annular airbags are in seamless contact with the basement membrane 301.

[0090] It should be pointed out that the inverted convex-shaped annular airbag can also be inflated. In other words, the inverted convex-shaped annular airbag can be in seamless contact with the basement membrane 301 when inflated, and can have a certain gap between the inverted convex-shaped annular airbag and the basement membrane 301 when not inflated.

[0091] In the following, unless otherwise specified, the description is made with the inverted convex-shaped annular airbag as the inflated state. In addition, the upright convex-shaped annular airbag and the fan-shaped airbag are described in the same manner as the inverted convex-shaped annular airbag.

[0092] In this embodiment, there are two inverted convex-shaped annular airbags, namely a first inverted convex-shaped annular airbag 304 and a second inverted convex-shaped annular airbag 305; the cross-sectional view of the second inverted convex-shaped annular airbag 305 along the direction parallel to the wafer surface is circular.

[0093] The first inverted convex-shaped annular airbag 304 and the second inverted convex-shaped annular airbag 305 are located inside the basement membrane 301 and are in seamless contact with the basement membrane 301 , that is, one end 304a of the first inverted convex-shaped annular airbag 304 and one end 305a of the second inverted convex-shaped annular airbag 305 are in seamless contact with the basement membrane 301 .

[0094] The shape of the inverted convex-shaped annular airbag in the cross section along the direction perpendicular to the wafer surface includes: an inverted convex shape.

[0095] The material constituting the inverted convex-shaped annular airbag includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane. In this embodiment, the material constituting the inverted convex-shaped annular airbag is fluorinated rubber.

[0096] The plurality of upright convex-shaped annular airbags and the plurality of inverted convex-shaped annular airbags are alternately arranged on the base film 301, and the side walls of the adjacent upright convex-shaped annular airbags and the inverted convex-shaped annular airbags collide with each other. This has the following beneficial effects: the risk of warping of the base film 301 in contact with the adjacent upright convex-shaped annular airbags and the inverted convex-shaped annular airbags is reduced, the overall flatness of the base film 301 is improved, and the fineness of the local adjustment of the base film 301 is improved, thereby improving the wafer grinding yield.

[0097] Continue to refer Figure 6 , taking the first upright convex-shaped annular airbag 302 and the first inverted convex-shaped annular airbag 304 as examples, the above beneficial effects are analyzed: the side walls of the adjacent first upright convex-shaped annular airbag 302 and the first inverted convex-shaped annular airbag 304 collide with each other, forming a first region Q1 and a second region Q2; when the first upright convex-shaped annular airbag 302 is inflated, a thrust in a direction parallel to the surface of the wafer is applied to the first region Q1, which increases the risk of the base film 301 being lifted at the contact point between the first region Q1 and the base film 301, resulting in the grinding pressure provided by the lifted base film 301 not being within the preset range, thereby reducing the grinding yield. In this embodiment, due to the existence of the second region Q2, a pulling force opposite to the thrust is provided to the first region Q1, reducing the probability of the base film 301 being lifted at the contact point between the first region Q1 and the base film 301, thereby improving the grinding yield.

[0098] The side walls of the adjacent upright convex-shaped annular airbags and the inverted convex-shaped annular airbags are in conflict with each other, that is, the side walls of the adjacent upright convex-shaped annular airbags are in seamless contact with the side walls of the upright convex-shaped annular airbags.

[0099] In the present embodiment, the first upright convex-shaped annular airbag 302, the second upright convex-shaped annular airbag 303, the first inverted convex-shaped annular airbag 304, and the second inverted convex-shaped annular airbag 305 are arranged alternately and spaced along the edge of the wafer pointing towards the center of the wafer in the order of the first upright convex-shaped annular airbag 302, the first inverted convex-shaped annular airbag 304, the second upright convex-shaped annular airbag 303, and the second inverted convex-shaped annular airbag 305.

[0100] The first inverted convex-shaped annular airbag 304 is in conflict with the first upright convex-shaped annular airbag 302 and the second upright convex-shaped annular airbag 303 respectively, that is, the first side wall 304b of the first inverted convex-shaped annular airbag 304 is in seamless contact with the second side wall 302b of the first upright convex-shaped annular airbag 302, and the second side wall 304c of the first inverted convex-shaped annular airbag 304 is in seamless contact with the first side wall 303c of the second upright convex-shaped annular airbag 303; the first side wall 305b of the second inverted convex-shaped annular airbag 305 is in seamless contact with the second side wall 303b of the second upright convex-shaped annular airbag 303, and the second side wall 305c of the second inverted convex-shaped annular airbag 305 is in seamless contact with the second side wall 303b of the second upright convex-shaped annular airbag 303.

[0101] Continue to refer Figure 6It should be noted that, in the present embodiment, the other end 302d of the first upright convex-shaped annular airbag 302, the other end 303d of the second upright convex-shaped annular airbag 303, the other end 304d of the first inverted convex-shaped annular airbag 304 and the other end 305d of the second inverted convex-shaped annular airbag 305 are all in contact with the first surface 203 of the spacer 201, that is, there is no gap in contact.

[0102] refer to Figures 8 to 10 , combined with Figure 4 ,in, Figure 8 is a top view of the second grinding sleeve located on the tubular peripheral support 200, Fig. 9 for Figure 8 Cross-section along E1E2; Fig.10 include Fig.10 (a) Fig.10 (b) Fig.10 (c) Fig.10 (d) where Fig.10 (a) Figure 8 Cross-section along F1F2, Fig.10 (b) Figure 8 Cross-section along G1G2, Fig.10 (c) Figure 8 Cross-section along H1H2, Fig.10 (d) Figure 8 Cross-section along J1J2.

[0103] The grinding head further includes: a second grinding sleeve 400, which is carried on the second surface 204 of the spacer 201 in the grinding head bracket. The second grinding sleeve 400 is used for grinding wafers.

[0104] The second grinding sleeve includes: an auxiliary film 405 .

[0105] The auxiliary film 405 provides a supporting basis for the plurality of fan-shaped airbags.

[0106] The auxiliary film 405 is suitable for elastic deformation along the axial direction of the second grinding sleeve. When grinding with the second grinding sleeve, the front side 405a of the auxiliary film 405 contacts the wafer, that is, the auxiliary film 405 is elastically deformed in a direction perpendicular to the surface of the wafer, and the auxiliary film 405 can be close to and away from the wafer; when grinding with the second grinding sleeve, the front side of the auxiliary film 405 contacts the back side of the wafer to be ground.

[0107] The material of the auxiliary film 405 includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane. In this embodiment, the material of the auxiliary film 405 is fluorinated rubber.

[0108] The shape of the auxiliary film 405 includes one or more of a circular cylinder, an elliptical cylinder, and a square cylinder. In this embodiment, the shape of the auxiliary film 405 is a circular cylinder.

[0109] The second grinding sleeve includes: a plurality of fan-shaped air bags, which are located in the auxiliary film 405 and are in conflict with the back side of the auxiliary film 405, the centers of the fan-shaped air bags are consistent, and the side walls of adjacent fan-shaped air bags are in conflict. It has the following beneficial effects: according to the different film thickness distribution on the wafer, each fan-shaped air bag can independently provide a grinding pressure adapted to the film thickness distribution to grind the front side of the wafer, thereby improving the wafer grinding yield.

[0110] A plurality of fan-shaped airbags are located in the auxiliary film 405 and in contact with the back side of the auxiliary film 405 . The area of ​​each fan-shaped airbag is smaller than that of the auxiliary film 405 , and each fan-shaped airbag is in seamless contact with the auxiliary film 405 .

[0111] In this embodiment, the number of the fan-shaped airbags is 4, namely the first fan-shaped airbag 401, the second fan-shaped airbag 402, the third fan-shaped airbag 403, and the fourth fan-shaped airbag 404. The centers of the first fan-shaped airbag 401, the second fan-shaped airbag 402, the third fan-shaped airbag 403, and the fourth fan-shaped airbag 404 are the same, which is the center O.

[0112] The first fan-shaped airbag 401, the second fan-shaped airbag 402, the third fan-shaped airbag 403, and the fourth fan-shaped airbag 404 are respectively located in the auxiliary film 405 and are in seamless contact with the auxiliary film 405, that is, the first end 401a of the first fan-shaped airbag 401 is in seamless contact with the auxiliary film 405, the first end 402a of the second fan-shaped airbag 402 is in seamless contact with the auxiliary film 405, the first end 403a of the third fan-shaped airbag 403 is in seamless contact with the auxiliary film 405, and the first end 404a of the fourth fan-shaped airbag 404 is in seamless contact with the auxiliary film 405.

[0113] In addition, the second end 401b of the first fan-shaped airbag 401 is in seamless contact with the second surface 204 of the spacer 201, the second end 402b of the second fan-shaped airbag 402 is in seamless contact with the second surface 204 of the spacer 201, and the third end 403b of the third fan-shaped airbag 403 is in seamless contact with the second surface 204 of the spacer 201, and the second end 404b of the fourth fan-shaped airbag 404 is in seamless contact with the second surface 204 of the spacer 201.

[0114] The material constituting the fan-shaped airbag includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane. In this embodiment, the material of the auxiliary fan-shaped airbag is fluorinated rubber.

[0115] The side walls of the adjacent fan-shaped airbags are in conflict with each other, that is, the side walls of the adjacent fan-shaped airbags are in contact with each other without any gap.

[0116] Continue to refer Figure 6 The grinding head also includes: adjacent first redundant airbags 500 and second redundant airbags 501.

[0117] The first redundant airbag 500 is located in the base film 301 and contacts the back side of the base film 301 and a portion of the inner wall 202 of the tubular peripheral support 200. That is, the first redundant airbag 500 is located in the base film 301 and contacts the back side of the base film 301 and a portion of the inner wall 202 of the tubular peripheral support 200 without a gap, which has the following beneficial effects:

[0118] First, when the wafer is ground, the probability of the wafer edge warping is reduced, so that the grinding pressure of the first redundant airbag 500 on the wafer edge film layer is within a preset range, thereby improving the grinding yield.

[0119] Second, the adjacent first redundant airbag 500 and second redundant airbag 501 can reduce the risk of the edge of the first grinding sleeve being lifted, thereby improving the grinding yield. The reasons are analyzed as follows:

[0120] The airbag at the edge of the first grinding sleeve is the first upright convex annular airbag 302, and the first side wall 302c of the first upright convex annular airbag 302 includes: a third area Q3, when the first upright convex annular airbag 302 is inflated, a thrust will be given to the third area Q3 in parallel with the wafer surface, increasing the risk of the base film 301 connected to the third area Q3 being lifted, causing the grinding pressure on the wafer near the third area Q3 to be not within the preset range, thereby reducing the grinding yield. In this embodiment, the first redundant airbag 500 provides a force opposite to the thrust to the third area Q3, and at the same time, the second redundant airbag 501, along the direction perpendicular to the wafer, provides a pressure to the third area Q3 in the direction perpendicular to the wafer, reducing the risk of the base film 301 connected to the third area Q3 being lifted, thereby improving the grinding yield.

[0121] In this embodiment, the shape of the cross section of the first redundant airbag 500 along the direction perpendicular to the wafer surface includes one or more of a square, a circle, and a triangle. In this embodiment, the shape of the cross section of the first redundant airbag 500 along the direction perpendicular to the wafer surface is a square.

[0122] The material of the first redundant airbag 500 includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane. In this embodiment, the material of the first redundant airbag 500 is fluorinated rubber.

[0123] The second redundant airbag 501 is located in the basement membrane 301 and is in conflict with the first surface 203 of the spacer 201 and a portion of the inner wall 202 of the tubular peripheral support 200. That is, the second redundant airbag 501 is located in the basement membrane 301 and is in seamless contact with the first surface 203 of the spacer 201 and a portion of the inner wall 202 of the tubular peripheral support 200.

[0124] The shape of the cross section of the second redundant airbag 501 along the direction perpendicular to the wafer surface includes one or more of square, circle, and triangle. In this embodiment, the shape of the cross section of the second redundant airbag 501 along the direction perpendicular to the wafer surface is a square.

[0125] The material of the second redundant airbag 501 includes: one or more of fluorinated rubber, vulcanized rubber and polyurethane. In this embodiment, the material of the second redundant airbag 501 is fluorinated rubber.

[0126] Continue to refer Figure 6 and Figure 7 , combined with Figure 4 In this embodiment, the number of the first redundant airbag is 1, namely the first redundant airbag 500; the number of the second redundant airbag is 1, namely the second redundant airbag 501. The first redundant airbag 500 and the second redundant airbag 501 are integrally formed, and the second redundant airbag 501 is located on the first redundant airbag 500.

[0127] The first side wall 500a of the first redundant airbag 500 is in seamless contact with a portion of the inner wall 202 of the tubular peripheral support 200, and the second side wall 500b of the first redundant airbag 500 is in seamless contact with the first side wall 302c of the first upright convex-shaped annular airbag 302; the first side wall 501a of the second redundant airbag 501 is in seamless contact with a portion of the inner wall 202 of the tubular peripheral support 200, and the second side wall 501b of the second redundant airbag 501 is in seamless contact with the first side wall 302c of the first upright convex-shaped annular airbag 302.

[0128] It should be noted that the first upright convex-shaped annular airbag 302, the second upright convex-shaped annular airbag 303, the first inverted convex-shaped annular airbag 304, the second inverted convex-shaped annular airbag 305, the first redundant airbag 500, and the second redundant airbag 501 are integrally formed with the base film 301, which improves the efficiency of manufacturing the first grinding sleeve.

[0129] The first fan-shaped airbag 401 , the second fan-shaped airbag 402 , the third fan-shaped airbag 403 , the fourth fan-shaped airbag 404 and the auxiliary film 405 are integrally formed, thereby improving the efficiency of manufacturing the second grinding sleeve.

[0130] It should be noted that the area of ​​the cross section of the tubular peripheral support 200 along the direction parallel to the wafer surface is greater than or equal to the area of ​​the base film 301, and the area of ​​the base film 301 is greater than or equal to the area of ​​the wafer, which has the following beneficial effects. First, when the base film 301 adsorbs the wafer, the tubular peripheral support 200 is prevented from hitting the wafer to be ground; second, the film layer on the wafer can be covered by the base film 301 to improve the grinding yield.

[0131] The area of ​​the cross section of the tubular peripheral support 200 along the direction parallel to the wafer surface is greater than or equal to the area of ​​the auxiliary film 405, and the area of ​​the auxiliary film 405 is greater than or equal to the area of ​​the wafer, which has the following beneficial effects: first, when the auxiliary film 405 adsorbs the wafer, the tubular peripheral support 200 is prevented from colliding with the wafer to be ground; second, the film layer on the wafer can be covered by the auxiliary film 405 to improve the grinding yield.

[0132] The grinding head also includes: a pair of limiting protrusions, the first limiting protrusion in each pair of limiting protrusions is located on the first surface of the spacer 201, and the second limiting protrusion is located on the back side of the base film 301; wherein the two adjacent pairs of limiting protrusions are used to limit the upright convex-shaped annular airbag or the inverted convex-shaped annular airbag therebetween.

[0133] The first limiting protrusion and the second limiting protrusion are used to define the size of the upright convex-shaped annular airbag and the inverted convex-shaped annular airbag. The second limiting protrusion has the following beneficial effects: the second limiting protrusion is used to limit the upright convex-shaped annular airbag and the inverted convex-shaped annular airbag from expanding and contracting in a direction parallel to the wafer surface, but expanding and contracting in a direction perpendicular to the wafer surface, so that the upright convex-shaped annular airbag and the inverted convex-shaped annular airbag are adapted to the film thickness distribution, thereby improving the grinding yield.

[0134] Continue to refer Figure 7In this embodiment, the pair of limiting protrusions includes: a first pair of limiting protrusions, a second pair of limiting protrusions, a third pair of limiting protrusions, and a fourth pair of limiting protrusions. The first pair of limiting protrusions includes: a first limiting protrusion 601 and a second limiting protrusion 602; the second pair of limiting protrusions includes: a third limiting protrusion 603 and a fourth limiting protrusion 604; the third pair of limiting protrusions includes: a fifth limiting protrusion 605 and a sixth limiting protrusion 606; the fourth pair of limiting protrusions includes: a seventh limiting protrusion 607 and an eighth limiting protrusion 608. The first limiting protrusion 601, the third limiting protrusion 603, the fifth limiting protrusion 605, and the seventh limiting protrusion 607 are located on the first surface 203 of the spacer 201; the second limiting protrusion 602, the fourth limiting protrusion 604, the sixth limiting protrusion 606, and the eighth limiting protrusion 608 are located on the back side of the base film 301.

[0135] Continue to refer Figure 7 The two adjacent pairs of limiting protrusions are used to limit the upright convex-shaped annular airbag or the inverted convex-shaped annular airbag therebetween. In this embodiment, the adjacent first limiting protrusion 601, the second limiting protrusion 602, the third limiting protrusion 603, and the fourth limiting protrusion 604 limit the first upright convex-shaped annular airbag 302; the adjacent third limiting protrusion 603, the fourth limiting protrusion 604, the fifth limiting protrusion 605, and the sixth limiting protrusion 606 limit the first inverted convex-shaped annular airbag 304; the adjacent fifth limiting protrusion 605, the sixth limiting protrusion 606, the seventh limiting protrusion 607, and the eighth limiting protrusion 608 limit the second upright convex-shaped annular airbag 303; two groups of adjacent seventh limiting protrusions 607 and eighth limiting protrusions 608 limit the second inverted convex-shaped annular airbag 305.

[0136] In this embodiment, the adjacent first limiting protrusion 601 , the second limiting protrusion 602 and the inner wall 202 of the tubular periphery limit the first redundant airbag 500 and the second redundant airbag 501 .

[0137] One end of the airbag side wall is connected to the base film 301 through a limiting protrusion among adjacent limiting protrusions, and the other end of the airbag side wall is connected to the spacer 201 through another limiting protrusion among adjacent limiting protrusions, and the adjacent limiting protrusion is a part of the airbag side wall.

[0138] Combination Figure 6 and Figure 7In this embodiment, one end of the first side wall 302c of the first upright convex annular airbag 302 is connected to the spacer 201 through the first limiting protrusion 601 in the adjacent limiting protrusions, and the other end of the first side wall 302c of the first upright convex annular airbag 302 is connected to the base film 301 through the second limiting protrusion 602 in the adjacent limiting protrusions. The first limiting protrusion 601 and the second limiting protrusion 602 of the adjacent limiting protrusions are the first side wall 302c of the first upright convex annular airbag 302. A part; one end of the second side wall 302b of the first upright convex-shaped annular airbag 302 is connected to the spacer 201 through the third limiting protrusion 603 in the adjacent limiting protrusion, and the other end of the second side wall 302b of the first upright convex-shaped annular airbag 302 is connected to the base membrane 301 through the fourth limiting protrusion 604 in the adjacent limiting protrusion, and the third limiting protrusion 603 and the fourth limiting protrusion 604 of the adjacent limiting protrusion are a part of the second side wall 302b of the first upright convex-shaped annular airbag 302.

[0139] One end of the first side wall 304b of the first inverted convex annular airbag 304 is connected to the spacer 201 through the third limiting protrusion 603 in the adjacent limiting protrusions, and the other end of the first side wall 304b of the first inverted convex annular airbag 304 is connected to the basement membrane 301 through the fourth limiting protrusion 604 in the adjacent limiting protrusions. The third limiting protrusion 603 and the fourth limiting protrusion 604 of the adjacent limiting protrusions are part of the first side wall 304b of the first inverted convex annular airbag 304. One end of the second side wall 304c of the first inverted convex-shaped annular airbag 304 is connected to the spacer 201 through the fifth limiting protrusion 605 among the adjacent limiting protrusions, and the other end of the two side walls 304c of the first inverted convex-shaped annular airbag 304 is connected to the basement membrane 301 through the sixth limiting protrusion 606 among the adjacent limiting protrusions, and the fifth limiting protrusion 605 and the sixth limiting protrusion 606 of the adjacent limiting protrusions are part of the second side wall 304c of the first inverted convex-shaped annular airbag 304.

[0140] One end of the first side wall 303c of the second upright convex annular airbag 303 is connected to the spacer 201 through the fifth limiting protrusion 605 among the adjacent limiting protrusions, and the other end of the first side wall 303c of the second upright convex annular airbag 303 is connected to the base film 301 through the sixth limiting protrusion 606 among the adjacent limiting protrusions. The fifth limiting protrusion 605 and the sixth limiting protrusion 606 of the adjacent limiting protrusions are part of the first side wall 303c of the second upright convex annular airbag 303. One end of the second side wall 303b of the second upright convex-shaped annular airbag 303 is connected to the spacer 201 through the 7th limiting protrusion 607 among the adjacent limiting protrusions, and the other end of the second side wall 303b of the second upright convex-shaped annular airbag 303 is connected to the base membrane 301 through the 8th limiting protrusion 608 among the adjacent limiting protrusions. The 7th limiting protrusion 607 and the 8th limiting protrusion 608 of the adjacent limiting protrusions are part of the second side wall 303b of the second upright convex-shaped annular airbag 303.

[0141] One end of the first side wall 305b of the second inverted convex annular airbag 305 is connected to the spacer 201 through the seventh limiting protrusion 607 among the adjacent limiting protrusions, and the other end of the first side wall 305b of the second inverted convex annular airbag 305 is connected to the basement membrane 301 through the eighth limiting protrusion 608 among the adjacent limiting protrusions. The seventh limiting protrusion 607 and the eighth limiting protrusion 608 of the adjacent limiting protrusions are part of the first side wall 305b of the second inverted convex annular airbag 305. One end of the second side wall 305c of the second inverted convex-shaped annular airbag 305 is connected to the spacer 201 through the 7th limiting protrusion 607 among the adjacent limiting protrusions, and the other end of the second side wall 305c of the second inverted convex-shaped annular airbag 305 is connected to the basement membrane 301 through the 8th limiting protrusion 608 among the adjacent limiting protrusions. The 7th limiting protrusion 607 and the 8th limiting protrusion 608 of the adjacent limiting protrusions are part of the second side wall 305c of the second inverted convex-shaped annular airbag 305.

[0142] The material of the limiting protrusion includes: one or more of nylon, polytetrafluoroethylene, polyphenylene ether, stainless steel, and aluminum alloy. In this embodiment, the material of the limiting protrusion is nylon.

[0143] The shape of the cross section of the limiting protrusion along the direction perpendicular to the wafer surface includes one or more of circular, square, elliptical, triangular, and polygonal shapes. In this embodiment, the shape of the cross section of the limiting protrusion along the direction perpendicular to the wafer surface is square.

[0144] The grinding head further includes: a limiting structure, which is located on the second surface of the spacer 201 or on the back surface of the auxiliary film 405; wherein adjacent limiting structures are used to limit the fan-shaped airbags therebetween.

[0145] In this embodiment, the limiting structure is located on the back side of the auxiliary film 405, and has the following beneficial effects: the limiting structure is used to limit the fan-shaped airbag from expanding and contracting in a direction parallel to the wafer surface, but expanding and contracting in a direction perpendicular to the wafer surface, so that the fan-shaped airbag is adapted to the film thickness distribution, thereby improving the grinding yield.

[0146] refer to Figures 8 to 10 In this embodiment, the limiting structure includes: a first limiting structure 406, a second limiting structure 407, a third limiting structure 408, and a fourth limiting structure 409; the adjacent first limiting structure 406 and second limiting structure 407 are used to limit the second fan-shaped airbag 402 therebetween, so that the second fan-shaped airbag 402 expands and contracts along a direction perpendicular to the wafer surface; the adjacent second limiting structure 407 and third limiting structure 408 are used to limit the third fan-shaped airbag 403 therebetween, so that The third fan-shaped airbag 403 is made to expand and contract along a direction perpendicular to the surface of the wafer; the adjacent third limiting structure 408 and fourth limiting structure 409 are used to limit the fourth fan-shaped airbag 404 therebetween, so that the fourth fan-shaped airbag 404 expands and contracts along a direction perpendicular to the surface of the wafer; the adjacent fourth limiting structure 409 and first limiting structure 406 are used to limit the first fan-shaped airbag 401 therebetween, so that the first fan-shaped airbag 401 expands and contracts along a direction perpendicular to the surface of the wafer.

[0147] The material of the limiting structure includes: one or more of nylon, polytetrafluoroethylene, polyphenylene ether, stainless steel, and aluminum alloy. In this embodiment, the material of the limiting structure is nylon.

[0148] The shape of the cross section of the limiting structure along the direction perpendicular to the wafer surface includes one or more of circular, square, elliptical, triangular, and polygonal shapes. In this embodiment, the shape of the cross section of the limiting structure along the direction perpendicular to the wafer surface is square.

[0149] A first air hole (not shown) is provided on the paired limiting protrusions, and a second air hole (not shown) adapted to the first air hole is provided on the base film 301, that is, the second air hole is connected with the first air hole, so that the first grinding sleeve can adsorb the back side of the wafer through the second air hole to achieve grinding of the wafer.

[0150] The shape of the first air hole includes: one or more of a circle, an ellipse, a square, a triangle, and a polygon. In this embodiment, the shape of the first air hole is a circle.

[0151] The limiting structure is provided with a third air hole (not shown), and the auxiliary film 405 has a fourth air hole (not shown) adapted to the third air hole, that is, the fourth air hole is connected to the third air hole, so that the second grinding sleeve can adsorb the back side of the wafer through the fourth air hole to achieve grinding of the wafer.

[0152] A grinding device, comprising the aforementioned grinding head, further comprising: a control system (not shown);

[0153] The control system is independently connected to the first pore, the second pore, the third pore, and the fourth pore. The control system controls the first grinding sleeve to adsorb the wafer through the first pore and the second pore, that is, controls the second pore on the base film 301 to adsorb the wafer. The control system controls the second grinding sleeve to adsorb the back of the wafer through the third pore and the fourth pore, that is, controls the fourth pore on the auxiliary film 405 to adsorb the back of the wafer.

[0154] The control system is also independently connected to each upright convex-shaped annular airbag, each inverted convex-shaped annular airbag, each fan-shaped airbag, the first redundant airbag 500 and the second redundant airbag 501; the control system independently controls each upright convex-shaped annular airbag, each inverted convex-shaped annular airbag, each fan-shaped airbag, the first redundant airbag 500 and the second redundant airbag 501 to expand and contract in a direction perpendicular to the wafer surface.

[0155] It should be noted that the control system inflates each upright convex-shaped annular airbag, each inverted convex-shaped annular airbag, each fan-shaped airbag, the first redundant airbag 500 and the second redundant airbag 501 to control each upright convex-shaped annular airbag, each inverted convex-shaped annular airbag, each fan-shaped airbag, the first redundant airbag 500 and the second redundant airbag 501 to expand in a direction perpendicular to the surface of the wafer so as to apply grinding pressure to the base film 301 on the wafer; the control system evacuates air from each upright convex-shaped annular airbag, each inverted convex-shaped annular airbag, each fan-shaped airbag, the first redundant airbag 500 and the second redundant airbag 501 to control each upright convex-shaped annular airbag, each inverted convex-shaped annular airbag, each fan-shaped airbag, the first redundant airbag 500 and the second redundant airbag 501 to contract in a direction perpendicular to the surface of the wafer so as to restore the base film 301 and the airbags to the state before inflation.

[0156] refer to Figure 11 to Figure 12 , combined with Figure 4, is a schematic diagram of the structure of a grinding head according to an embodiment of the present invention, wherein: Fig.11 is a top view of a grinding head according to an embodiment of the present invention, Fig.12 for Fig.11 Cross-sectional view along the K1K2 direction.

[0157] It should be noted that the structure of the grinding head of the embodiment of the present invention includes: the aforementioned grinding head bracket, the first grinding sleeve 300, the second grinding sleeve 400, the tubular peripheral bracket 200, the limiting protrusion, and the limiting structure.

[0158] The grinding head support includes: a tubular peripheral support 200 and a spacer 201 .

[0159] In this embodiment, the first grinding sleeve 300 is located on the first surface 203 of the spacer 201, and the second grinding sleeve 400 is located on the second surface 204 of the spacer 201. In other embodiments, the first grinding sleeve 300 is located on the second surface 204 of the tubular peripheral bracket 200, and the first grinding sleeve 300 is located on the first surface 203 of the spacer 201.

[0160] In order to solve the technical problem, the present invention also provides a grinding method corresponding to the grinding head.

[0161] Fig.13 It is a schematic flow chart of a grinding method corresponding to a grinding head according to an embodiment of the present invention.

[0162] The grinding method of the embodiment of the present invention is applied to a grinding head. The grinding head comprises: a first grinding sleeve and / or a second grinding sleeve.

[0163] That is, the grinding head includes a first grinding sleeve, or the grinding head includes a second grinding sleeve, or the grinding head includes a first grinding sleeve and a second grinding sleeve.

[0164] Regarding the specific structures of the first grinding sleeve and the second grinding sleeve, reference may be made to the relevant description of the grinding head in the aforementioned embodiment, which will not be repeated here.

[0165] The present invention illustrates the grinding method corresponding to the grinding head by taking the grinding head comprising a first grinding sleeve and a second grinding sleeve.

[0166] refer to Fig.13 , combined with Figure 6 and Fig.12 , the grinding method comprises the following main steps:

[0167] Step S11: providing a wafer, wherein a film layer to be polished is disposed on a first surface of the wafer.

[0168] The film layer to be polished includes: a dielectric layer, a metal layer, etc. In this embodiment, the polishing method is described by taking the dielectric layer as an example.

[0169] The first surface of the wafer is the surface covered with a semiconductor device film layer, such as a surface covered with a dielectric layer.

[0170] Step S12: obtaining the film thickness of the film to be ground, and determining whether to select the first grinding sleeve or the second grinding sleeve to grind the film to be ground according to the distribution of the film thickness.

[0171] In this embodiment, the film layer to be ground is ground in the following order: obtaining the film thickness of the film layer to be ground, and determining whether to select the first grinding sleeve or the second grinding sleeve according to the distribution of the film thickness.

[0172] First, the film thickness of the film to be polished is obtained.

[0173] The thickness of the dielectric layer of the film layer to be polished on the first surface of the wafer is tested by an optical interferometer.

[0174] Second, determining whether to select the first grinding sleeve or the second grinding sleeve to grind the wafer according to the distribution of the film thickness.

[0175] In response to selecting the first grinding sleeve to grind the film layer to be ground, the method further includes: determining grinding parameters of the first grinding sleeve, and the grinding parameters include: grinding pressure and grinding time.

[0176] In this embodiment, the thickness of the dielectric layer of the film layer to be ground is divided into 5 film thickness annular partitions, namely the first film thickness annular partition, the second film thickness annular partition, the third film thickness annular partition, the fourth film thickness annular partition, and the fifth film thickness annular partition; the average thickness of the dielectric layer in the first film thickness annular partition is greater than the average thickness of the dielectric layer in the second film thickness annular partition, the average thickness of the dielectric layer in the second film thickness annular partition is greater than the average thickness of the dielectric layer in the third film thickness annular partition, the average thickness of the dielectric layer in the third film thickness annular partition is greater than the average thickness of the dielectric layer in the fourth film thickness annular partition, and the average thickness of the dielectric layer in the fourth film thickness annular partition is greater than the average thickness of the dielectric layer in the fifth film thickness annular partition. On the first grinding sleeve, there are: a first upright convex annular airbag 302, a second upright convex annular airbag 303, a first inverted convex annular airbag 304, a second inverted convex annular airbag 305, a first redundant airbag 500, and a second redundant airbag 501. The first upright convex-shaped annular airbag 302 corresponds to the first film thickness annular partition, the first inverted convex-shaped annular airbag 304 corresponds to the second film thickness annular partition, the second upright convex-shaped annular airbag 303 corresponds to the third film thickness annular partition, the second inverted convex-shaped annular airbag 305 corresponds to the fourth film thickness annular partition, and the first redundant airbag 500 corresponds to the fifth film thickness annular partition.

[0177] It should be noted that the average thickness of the dielectric layer in the first film thickness annular partition is greater than the average thickness of the dielectric layer in the second film thickness annular partition, the average thickness of the dielectric layer in the second film thickness annular partition is greater than the average thickness of the dielectric layer in the third film thickness annular partition, the average thickness of the dielectric layer in the third film thickness annular partition is greater than the average thickness of the dielectric layer in the fourth film thickness annular partition, and the average thickness of the dielectric layer in the fourth film thickness annular partition is greater than the average thickness of the dielectric layer in the fifth film thickness annular partition. This is only an example, but the present invention is not limited thereto.

[0178] The grinding pressure is determined according to the average thickness of the dielectric layer in the annular partition of the film thickness.

[0179] In this embodiment, the control system controls the gas pressure of the first upright convex-shaped annular airbag 302 to be greater than the gas pressure of the first inverted convex-shaped annular airbag 304, so that the grinding pressure of the first upright convex-shaped annular airbag 302 on the first film thickness annular partitioned wafer is greater than the grinding pressure of the first inverted convex-shaped annular airbag 304 on the second film thickness annular partitioned wafer. The control system controls the gas pressure of the first inverted convex-shaped annular airbag 304 to be greater than the gas pressure of the second upright convex-shaped annular airbag 303, so that the grinding pressure of the first inverted upright convex-shaped annular airbag on the second film thickness annular partitioned wafer is greater than the grinding pressure of the second upright convex-shaped annular airbag 303 on the third film thickness annular partitioned wafer. The control system controls the gas pressure of the second upright convex-shaped annular airbag 303 to be greater than the grinding pressure of the second inverted convex-shaped annular airbag 305 on the fourth film thickness annular partitioned wafer. The control system controls the gas pressure of the second inverted convex-shaped annular airbag 305 to be greater than the grinding pressure exerted by the first redundant airbag 500 on the fifth film thickness annular partitioned wafer.

[0180] The grinding time is determined according to the average thickness of the dielectric layer in the annular partition of the film thickness.

[0181] In this embodiment, the grinding time of the first upright convex-shaped annular airbag 302 on the first film thickness annular partitioned wafer is greater than the grinding time of the first inverted convex-shaped annular airbag 304 on the second film thickness annular partitioned wafer; the grinding time of the first inverted upright convex-shaped annular airbag on the second film thickness annular partitioned wafer is greater than the grinding time of the second upright convex-shaped annular airbag 303 on the third film thickness annular partitioned wafer; the grinding time of the second upright convex-shaped annular airbag 303 on the third film thickness annular partitioned wafer is greater than the grinding time of the second inverted convex-shaped annular airbag 305 on the fourth film thickness annular partitioned wafer; the grinding time of the second inverted upright convex-shaped annular airbag on the fourth film thickness annular partitioned wafer is greater than the grinding time of the first redundant airbag 500 on the fifth film thickness annular partitioned wafer.

[0182] The wafer is ground according to the determined grinding pressure and grinding time corresponding to the first grinding sleeve.

[0183] The control system controls the first air hole and the second air hole to fix the second surface opposite to the first surface of the wafer on the base film 301 of the first grinding sleeve for grinding, so as to make the dielectric layer on the first surface of the wafer flat.

[0184] In the above application scenarios, when the flatness of the previous material layer (such as a dielectric layer, a metal layer, etc.) is insufficient, the flatness of the layer to be ground can be improved by adopting the grinding method in the embodiment of the present invention, but the specific application scenarios of the embodiment of the present invention are not limited to this.

[0185] In response to selecting the second polishing sleeve to polish the film layer to be polished, the method further includes: determining polishing parameters of the second polishing sleeve, and the polishing parameters include: polishing pressure and polishing time.

[0186] In this embodiment, the thickness of the dielectric layer of the film layer to be ground is divided into four film thickness fan-shaped partitions, namely the first film thickness fan-shaped partition, the first film thickness fan-shaped partition, the third film thickness fan-shaped partition, and the fourth film thickness fan-shaped partition; the average thickness of the dielectric layer in the first film thickness fan-shaped partition is greater than the average thickness of the dielectric layer in the second film thickness fan-shaped partition, the average thickness of the dielectric layer in the second film thickness fan-shaped partition is greater than the average thickness of the dielectric layer in the third film thickness fan-shaped partition, and the average thickness of the dielectric layer in the third film thickness fan-shaped partition is greater than the average thickness of the dielectric layer in the fourth film thickness fan-shaped partition. The second grinding sleeve includes: a first fan-shaped airbag 401, a second fan-shaped airbag 402, a third fan-shaped airbag 403, and a fourth fan-shaped airbag 404. The first fan-shaped airbag 401 corresponds to the first film thickness fan-shaped partition, the second fan-shaped airbag 402 corresponds to the second film thickness fan-shaped partition, the third fan-shaped airbag 403 corresponds to the third film thickness fan-shaped partition, and the fourth fan-shaped airbag 404 corresponds to the fourth film thickness fan-shaped partition.

[0187] The grinding pressure is determined according to the average thickness of the dielectric layer in the film thickness sector area.

[0188] In this embodiment, the control system controls the gas pressure of the first fan-shaped airbag 401 to be greater than that of the second fan-shaped airbag 402, so that the grinding pressure of the first fan-shaped airbag 401 on the first film thickness fan-shaped partitioned wafer is greater than the grinding pressure of the second fan-shaped airbag 402 on the second film thickness fan-shaped partitioned wafer; the control system controls the gas pressure of the second fan-shaped airbag 402 to be greater than that of the third fan-shaped airbag 403, so that the grinding pressure of the second fan-shaped airbag 402 on the second film thickness fan-shaped partitioned wafer is greater than the grinding pressure of the third fan-shaped airbag 403 on the third film thickness fan-shaped partitioned wafer; the control system controls the gas pressure of the third fan-shaped airbag 403 to be greater than that of the fourth fan-shaped airbag 404, so that the grinding pressure of the third fan-shaped airbag 403 on the third film thickness fan-shaped partitioned wafer is greater than the grinding pressure of the fourth fan-shaped airbag 404 on the fourth film thickness fan-shaped partitioned wafer.

[0189] The grinding time is determined according to the average thickness of the dielectric layer in the film thickness sector area.

[0190] In this embodiment, the grinding time of the first fan-shaped airbag 401 on the first film thickness fan-shaped partitioned wafer is greater than the grinding time of the second fan-shaped airbag 402 on the second film thickness fan-shaped partitioned wafer; the grinding time of the second fan-shaped airbag 402 on the second film thickness fan-shaped partitioned wafer is greater than the grinding time of the third fan-shaped airbag 403 on the third film thickness fan-shaped partitioned wafer; the grinding time of the third fan-shaped airbag 403 on the third film thickness fan-shaped partitioned wafer is greater than the grinding time of the fourth fan-shaped airbag 404 on the fourth film thickness fan-shaped partitioned wafer.

[0191] The wafer is ground according to the determined grinding pressure and grinding time corresponding to the second grinding sleeve.

[0192] The control system controls the third air hole and the fourth air hole to fix the second surface of the wafer opposite to the first surface on the auxiliary film 405 of the second grinding sleeve for grinding, so that the wafer obtains a flat surface.

[0193] It should be noted that, in this embodiment, the control system, the first air hole, the second air hole, the third air hole and the fourth air hole can refer to the description of the control system in the aforementioned grinding equipment and will not be described here.

[0194] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A grinding head, characterized in that: include: Grinding head bracket; A first grinding sleeve is carried in the grinding head bracket, and the first grinding sleeve comprises: A base film, adapted to undergo elastic deformation along the axial direction of the first grinding sleeve, wherein the front surface of the base film contacts the wafer to be ground when the first grinding sleeve is used for grinding; One or more upright convex annular air cells, located in the basement membrane and in contact with the back side of the basement membrane; One or more inverted convex-shaped annular air cells, located in the basement membrane and in contact with the back side of the basement membrane; The plurality of upright convex-shaped annular airbags and the plurality of inverted convex-shaped annular airbags are alternately arranged on the basement membrane, and the side walls of adjacent upright convex-shaped annular airbags and inverted convex-shaped annular airbags are in conflict with each other.

2. The grinding head according to claim 1, characterized in that: The grinding head bracket comprises: a tubular peripheral support; A spacer connected to the inner wall of the tubular peripheral support, wherein the spacer and the peripheral support are in an H shape in a cross section perpendicular to the surface of the basement membrane; Wherein, the first grinding sleeve is carried on the first surface of the spacer in the grinding head bracket.

3. The grinding head according to claim 2, characterized in that: The grinding head also includes: The second grinding sleeve is carried on the second surface of the spacer in the grinding head bracket, and the second grinding sleeve includes: An auxiliary film, adapted to undergo elastic deformation along the axial direction of the second grinding sleeve, wherein the front surface of the auxiliary film contacts the wafer during grinding by the second grinding sleeve; A plurality of fan-shaped air bags are located in the auxiliary film and are in conflict with the back surface of the auxiliary film. The centers of the fan-shaped air bags are consistent, and the side walls of adjacent fan-shaped air bags are in conflict with each other.

4. The grinding head according to claim 3, characterized in that: The grinding head further comprises: a limiting structure located on the second surface of the spacer or on the back surface of the auxiliary film; Wherein, adjacent limiting structures are used to limit the fan-shaped airbags therebetween.

5. The grinding head according to claim 4, characterized in that: The limiting structure is provided with a third air hole, and the auxiliary film is provided with a fourth air hole adapted to the third air hole.

6. The grinding head according to claim 3, characterized in that: The material of the base film includes one or more of fluorinated rubber, vulcanized rubber and polyurethane, the material constituting the upright convex-shaped annular airbag includes one or more of fluorinated rubber, vulcanized rubber and polyurethane, and the material constituting the side wall of the inverted convex-shaped annular airbag includes one or more of fluorinated rubber, vulcanized rubber and polyurethane; The material of the auxiliary membrane includes one or more of fluorinated rubber, vulcanized rubber and polyurethane, and the material constituting the fan-shaped airbag includes one or more of fluorinated rubber, vulcanized rubber and polyurethane.

7. The grinding head according to claim 3, characterized in that: The shape of the cross section of the upright convex-shaped annular airbag along the direction perpendicular to the wafer surface includes: a convex shape, and the shape of the cross section of the inverted convex-shaped annular airbag along the direction parallel to the wafer surface includes: an inverted convex shape; The shape of the base film includes: one or more of a circular cylinder, an elliptical cylinder, and a square cylinder; The shape of the auxiliary film includes: one or more of a circular cylinder, an elliptical cylinder, and a square cylinder; The shape of the spacer includes one or more of a circular cylinder, an elliptical cylinder, and a square cylinder.

8. The grinding head according to claim 3, characterized in that: The cross-sectional area of ​​the tubular peripheral support in the direction parallel to the wafer surface is greater than or equal to the area of ​​the base film, and the area of ​​the base film is greater than or equal to the area of ​​the wafer; The cross-sectional area of ​​the tubular peripheral support in a direction parallel to the wafer surface is greater than or equal to the area of ​​the auxiliary film, and the area of ​​the auxiliary film is greater than or equal to the area of ​​the wafer.

9. The grinding head according to claim 2, characterized in that: The grinding head also includes: Pairs of limiting protrusions, wherein a first limiting protrusion in each pair of limiting protrusions is located on the first surface of the spacer, and a second limiting protrusion is located on the back surface of the base film; Among them, two adjacent pairs of limiting protrusions are used to limit the upright convex-shaped annular airbag or the inverted convex-shaped annular airbag therebetween.

10. The grinding head according to claim 9, characterized in that: The paired limiting protrusions are provided with first pores, and the base film is provided with second pores matched with the first pores.

11. The grinding head according to claim 2, characterized in that: Also includes: adjacent first redundant airbag and second redundant airbag; Wherein, the first redundant airbag is located in the basement membrane and conflicts with the back side of the basement membrane and a portion of the inner wall of the tubular peripheral support; The second redundant airbag is located in the basement membrane and contacts the first surface of the spacer and a portion of the inner wall of the tubular peripheral support.

12. The grinding head according to claim 11, characterized in that: The cross-sectional shape of the first redundant airbag along the direction perpendicular to the wafer surface includes one or more of square, circle, and triangle. The cross-sectional shape of the second redundant airbag along the direction perpendicular to the wafer surface includes one or more of square, circle, and triangle.

13. A grinding device comprising the grinding head according to any one of claims 1 to 12, characterized in that: Also includes: Control systems; The control system controls the first grinding sleeve to adsorb the wafer through the first air hole and the second air hole; The control system controls the second grinding sleeve to adsorb the wafer through the third air hole and the fourth air hole; The control system independently controls each upright convex-shaped annular airbag, each inverted convex-shaped annular airbag, each fan-shaped airbag, the first redundant airbag and the second redundant airbag to expand and contract in a direction perpendicular to the wafer surface.

14. A grinding method, applied to a grinding head, characterized in that: The grinding head comprises the first grinding sleeve as claimed in claim 1, and / or comprises the second grinding sleeve as claimed in claim 3: The grinding method comprises: Providing a wafer, wherein a film layer to be polished is provided on a first surface of the wafer; The film thickness of the film layer to be ground is obtained, and according to the distribution of the film thickness, it is determined whether to select the first grinding sleeve or the second grinding sleeve to grind the film layer to be ground.

15. The grinding method according to claim 14, characterized in that: In response to selecting the first grinding sleeve to grind the film layer to be ground, the method further includes: Determining grinding parameters of the first grinding sleeve, wherein the grinding parameters include: grinding pressure and grinding time; The second surface opposite to the first surface of the wafer is fixed on the base film of the first grinding sleeve for grinding.

16. The grinding method according to claim 14, characterized in that: In response to selecting the second grinding sleeve to grind the film layer to be ground, the method further includes: Determining grinding parameters of the second grinding sleeve, wherein the grinding parameters include: grinding pressure and grinding time; The second surface opposite to the first surface of the wafer is fixed on the base film of the second grinding sleeve for grinding.

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