Wafer grinding piece and manufacturing method thereof, grinding equipment and method for processing wafer

Abstract

The embodiment of the invention discloses a wafer grinding piece, a manufacturing method of the wafer grinding piece, grinding equipment and a method for machining a wafer, relates to the technical field of grinding, and solves the problem that an existing chemical mechanical polishing machine is unstable in polishing rate. The wafer grinding piece comprises a substrate and a grinding material layer, and the grinding material layer is arranged on the substrate. The abrasive material layer comprises a first binder, a first abrasive material and a photodecomposition photosensitizer. The first abrasive and the photodecomposition photosensitizer are dispersed in the first binder and are bonded by the first binder. The wafer grinding piece is used in cooperation with a plurality of light-emitting devices, chemical bond breakage of the photolysis type photosensitizer of the grinding layer and decomposition of the photolysis type photosensitizer can be controlled by controlling starting and stopping of the light-emitting devices, and therefore the dissolving speed of the first grinding material in the area is increased. Therefore, the dissolution rate of the first abrasive in different areas of the grinding layer on the wafer grinding piece is accurately controlled, and the polishing rate of the grinding equipment is stable.

Description

Technical Field

[0001] The present application relates to the field of grinding technology, and in particular to a wafer grinding piece and a manufacturing method thereof, a grinding device and a method for processing a wafer. Background Art

[0002] Polishing pad is one of the important components of semiconductor grinding and polishing equipment. Polishing pad is formed by fixing polishing particles on a sheet with a binder. Taking chemical mechanical polisher as an example, the polishing pad is installed at a position opposite to the wafer. By rotating the polishing pad relative to the wafer, or rotating the wafer relative to the polishing pad, and spraying polishing liquid, moving pressure and friction are formed between the grinding disc and the wafer. Thus, grinding and polishing of the wafer surface are achieved. However, the existing chemical mechanical polisher has the problem of unstable polishing rate. Summary of the invention

[0003] The embodiments of the present application provide a wafer grinding piece and a manufacturing method thereof, a grinding device and a method for processing a wafer, which solve the problem of unstable polishing rate of existing chemical mechanical polishers.

[0004] In order to achieve the above objectives, this application adopts the following technical solutions:

[0005] In the first aspect, an embodiment of the present application provides a wafer grinding piece, which can be used in a mechanical polishing process, a chemical mechanical polishing process, and a thinning process. For example, the wafer grinding piece is a wafer grinding pad, a wafer polishing pad, or a wafer grinding wheel. The wafer grinding piece includes a substrate and an abrasive layer, wherein the substrate can serve as a supporting layer. The abrasive layer is disposed on the substrate. The abrasive layer includes a first abrasive, a photodecomposable photosensitizer, and a first adhesive. The first abrasive and the photodecomposable photosensitizer are dispersed in the first adhesive and bonded by the first adhesive.

[0006] Compared with the prior art, the grinding layer in the wafer grinding piece of the embodiment of the present application is additionally provided with a photodecomposable photosensitive agent. When the wafer is ground with the wafer grinding piece, a plurality of light-emitting devices can be added to the grinding equipment to work with the wafer grinding piece. In addition, the plurality of light-emitting devices are respectively arranged at positions corresponding to different regions of the grinding layer. When it is necessary to increase the dissolution rate of the first abrasive on certain regions corresponding to the wafer in the wafer grinding piece, the light-emitting device corresponding to the region can be turned on. The light beam emitted by the light-emitting device can break the chemical bonds of the photodecomposable photosensitive agent of the grinding layer in the region of the wafer grinding piece, and the photodecomposable photosensitive agent decomposes, so that the dissolution rate of the first abrasive in the region is accelerated. Therefore, by controlling the opening and closing of the plurality of light-emitting devices, the dissolution rate of the first abrasive in different regions on the wafer grinding piece can be accurately controlled. Thus, the dissolution rate of the first abrasive in different regions on the wafer grinding piece can be kept stable, so that the polishing rate of the grinding equipment (such as a wafer grinding and polishing machine) is stable. At the same time, the stress concentration problem in the grinding process is reduced, and the grinding uniformity of the first abrasive in the wafer grinding piece is improved.

[0007] Furthermore, in some embodiments of the present application, the above-mentioned photodegradable photosensitizer includes any one of dichromate compounds, diazonium salt compounds, silver salts, or alkali-soluble resins having alkylene oxide groups. For example, the photodegradable photosensitizer is diazonaphthoquinone (DNQ). These materials have the advantages of high resolution, good step coverage, good contrast, etc.

[0008] In some embodiments of the present application, the first abrasive in the abrasive layer includes any one or more of silicon oxide, cerium oxide, aluminum oxide or diamond powder. In addition, the abrasive layer may also include other components. The first abrasive can be used with other components to grind different materials. For example, chemical mechanical polishing can be performed on silicon oxide, polysilicon, metal tungsten, metal copper, etc.

[0009] In addition, in some embodiments, a plurality of guide grooves are formed on the abrasive layer, and the plurality of guide grooves are arranged at intervals. When applied to a chemical mechanical polisher, the plurality of guide grooves can quickly and evenly guide the grinding liquid to improve the grinding uniformity.

[0010] Furthermore, in some embodiments of the present application, the groove wall of the above-mentioned guide groove is covered with a light shielding layer. The light beam emitted by the light emitting device is blocked by the light shielding layer and will not be irradiated on the groove wall of the guide groove, and the groove wall of the guide groove will not be accelerated to dissolve. Thus, the side wall of the guide groove is prevented from dissolving too quickly and breaking.

[0011] Similarly, since the bottom of the guide groove does not need to be ground or polished, it is usually unnecessary to increase the dissolution rate of the bottom of the guide groove. Therefore, in some embodiments of the present application, the bottom of the guide groove is also covered with a light shielding layer.

[0012] Based on this, the light-shielding layer on the groove wall and the groove bottom of the above-mentioned guide groove may include carbon powder to achieve light-proof performance. In addition, the light-shielding layer may also include a second abrasive, for example, the second abrasive is any one or more of silicon oxide compounds, cerium oxide compounds, aluminum oxide compounds or diamond powder, so that the light-shielding layer can also grind the wafer at the same time, maintaining the same grinding speed as the groove wall of the guide groove. In addition, the light-shielding layer on the groove wall and the groove bottom of the guide groove also includes a second adhesive, and the carbon powder and the second abrasive are dispersed in the second adhesive. The second adhesive can bond the carbon powder and the second abrasive together.

[0013] In the second aspect, the embodiment of the present application also includes a method for manufacturing a wafer grinding piece. The method for manufacturing a wafer grinding piece includes the following steps: mixing a first adhesive, a first abrasive and a photodecomposable photosensitizer to obtain a mixed liquid. Applying the mixed liquid on a substrate to form an abrasive layer. Curing the abrasive layer. The method for manufacturing a wafer grinding piece of the embodiment of the present application can realize the manufacture of the wafer grinding piece described in the above embodiment. Both can solve the same technical problems and obtain the same technical effects, which will not be repeated here.

[0014] Based on the above method, in some embodiments of the present application, between coating the mixed liquid on the substrate to form an abrasive layer and curing the abrasive layer, the method for manufacturing a wafer grinding piece further includes: forming a plurality of guide grooves on the abrasive layer. Thus, a wafer grinding piece with guide grooves is manufactured.

[0015] Furthermore, in some embodiments, after the abrasive layer is cured, the method for manufacturing a wafer grinding piece further includes: forming a light shielding layer on the surface of the abrasive layer away from the substrate. Curing the light shielding layer. Removing the light shielding layer from other areas of the abrasive layer except for the groove surface of the guide groove. Thus, a guide groove having a light shielding layer on both the groove wall and the groove bottom is formed.

[0016] In the third aspect, the embodiment of the present application also includes a grinding device, which can be a wafer thinning machine or a chemical mechanical polishing machine, etc. The grinding device includes a grinding piece loading device, the wafer grinding piece described in the above embodiment, a wafer loading device and a plurality of light-emitting devices. Among them, the wafer grinding piece can be arranged on the grinding piece loading device. The wafer loading device is used to load the wafer to be ground. The wafer grinding piece on the above-mentioned grinding piece loading device can be arranged relative to the wafer on the wafer loading device. The grinding piece loading device is used to drive the wafer grinding piece to rotate, or the wafer loading device is used to drive the wafer to rotate. Thereby, a moving pressure and friction force are formed between the wafer grinding piece and the wafer to realize the grinding, polishing or grinding thinning of the wafer by the wafer grinding piece. Multiple light-emitting devices are respectively arranged relative to multiple areas of the grinding layer in the wafer grinding piece. In addition, multiple light-emitting devices are used to control the dissolution of the photodecomposable photosensitizer in the wafer grinding piece. Thus, the grinding speed of different areas of the grinding layer in the wafer grinding piece is controlled, so that the dissolution rate of the first abrasive in different areas of the wafer grinding piece remains stable, so that the polishing rate of the grinding equipment (such as a wafer grinding and polishing machine) is stable.

[0017] Based on the above, in some embodiments of the present application, the above-mentioned photodecomposable photosensitizer is a dichromate compound or a diazonium salt compound, and the light-emitting device is an ultraviolet lamp. The above-mentioned photodecomposable photosensitizer is a silver salt, or an alkali-soluble resin having an alkylene oxide group, and the light-emitting device is an infrared lamp. Thus, it is suitable for wafer grinding parts of various materials.

[0018] Furthermore, in some embodiments of the present application, the above-mentioned grinding equipment also includes a polishing liquid supply device, which is used to supply polishing liquid.

[0019] In a fourth aspect, an embodiment of the present application also includes a method for processing a wafer using the grinding equipment of the above embodiment. The method includes the following steps: loading a wafer on a wafer loading device. Controlling the wafer grinding piece on the grinding piece loading device to contact the wafer on the wafer loading device. Controlling the rotation of the wafer grinding piece on the grinding piece loading device or the wafer on the wafer loading device to grind the wafer. Controlling the opening and closing of multiple light-emitting devices respectively to adjust the dissolution rate of the photodecomposable photosensitizer in the wafer grinding piece. Thus, the grinding equipment can control the grinding speed of the wafer by the wafer grinding piece, so that the polishing rate of the wafer is stable.

[0020] Furthermore, in some embodiments of the present application, after controlling the wafer grinding piece on the grinding piece loading device to contact the wafer on the wafer loading device, the method further includes: controlling the polishing liquid supply device to supply or stop supplying polishing liquid to the wafer grinding piece. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to illustrate the technical solution of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be described below.

[0022] Figure 1 This is a schematic diagram of the structure of the grinding equipment according to the embodiment of the present application;

[0023] Figure 2 This is a schematic diagram of the structure of a wafer grinding piece according to an embodiment of the present application;

[0024] Figure 3 A cross-sectional view of a wafer grinding piece according to an embodiment of the present application;

[0025] Figure 4 The three-dimensional structure diagram of the grinding equipment in the embodiment of the present application is a wafer thinning machine;

[0026] Figure 5 This is a schematic diagram of the structure of a wafer thinning machine as the grinding device in an embodiment of the present application;

[0027] Figure 6 The grinding device of the embodiment of the present application is a schematic structural diagram of a wafer thinning machine including a polishing liquid supply device;

[0028] Figure 7 A schematic diagram of the structure of a wafer thinning machine having a wafer polishing pad with a guide groove according to an embodiment of the present application;

[0029] Figure 8 This is a schematic structural diagram of a wafer polishing pad with a guide groove according to an embodiment of the present application;

[0030] Fig. 9 The wafer polishing pad having a guide groove and a first light shielding layer according to an embodiment of the present application;

[0031] Fig.10 The wafer polishing pad of the embodiment of the present application has a guide groove, a first light shielding layer and a second light shielding layer;

[0032] Fig.11 This is a schematic diagram of the three-dimensional structure of a chemical mechanical polisher in an embodiment of the present application;

[0033] Fig.12 A schematic diagram of the three-dimensional structure of a chemical mechanical polisher including a grinding slurry arm according to an embodiment of the present application;

[0034] Fig.13 The top view of the grinding device in the embodiment of the present application is a chemical mechanical polishing machine;

[0035] Fig.14 is a schematic structural diagram of a mixing device;

[0036] Fig.15 It is a structural schematic diagram of a wafer grinding piece processing equipment;

[0037] Fig.16 for Fig.15 Enlarged view of part A in the middle;

[0038] Fig.17 for Fig.15 Enlarged view of middle part B;

[0039] Fig.18 This is a schematic cross-sectional view of a wafer grinding piece in which the groove wall of the guide groove according to an embodiment of the present application has a light shielding layer.

[0040] Figure Number:

[0041] 1000-grinding equipment; 1000a-wafer thinning machine; 1000b-chemical mechanical polishing machine; 100-wafer grinding piece; 100a-wafer grinding wheel; 101-first wafer grinding wheel; 100b-wafer grinding pad; 1-substrate; 11-first surface; 2-abrasive layer; 21-first adhesive; 22-first abrasive; 23-photodecomposable photosensitizer; 24-mixed liquid; 3-guiding groove; 4-light shielding layer; 4a-first light shielding layer; 4b-second light shielding layer; 200-grinding piece loading device; 200a-rotating axis; 200b-rotating disk; 300-wafer loading device; 300a-workbench; 301-clamping device; 300b-wafer holder; 400-light-emitting device; 500-polishing liquid supply device; 500b-grinding slurry arm; 2000-wafer; 3000-mixing device; 4000-grinding processing equipment; 10-unwinding roller; 20-transmission workbench; 30-first coating device; 40-abrasive layer curing device; 50-pattern printing roller; 60-second coating device; 70-light-shielding layer curing device; 80-grinding device. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0043] In the following, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0044] In addition, in the present application, directional terms such as "up", "down", "left", "right", "horizontal" and "vertical" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to the changes in the orientation of the components in the drawings.

[0045] In this application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can refer to the connection of mechanical structure or physical structure. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be directly connected or indirectly connected through an intermediate medium. It can also be understood as the physical contact and electrical conduction of components, and it can also be understood as the form in which different components in the circuit structure are connected through physical lines such as PCB copper foil or wires that can transmit electrical signals.

[0046] The embodiment of the present application includes a grinding device, which can be used for fine grinding, rough grinding or polishing of a wafer, etc. Therefore, it can be applied to a mechanical polishing process, a chemical mechanical polishing process or a semiconductor thinning process.

[0047] Figure 1 The partial structure of the grinding device of the embodiment of the present application is shown. Figure 1 The grinding device 1000 includes a wafer grinding piece 100, a grinding piece loading device 200 and a wafer loading device 300. The wafer grinding piece 100 is loaded on the grinding piece loading device 200 and is arranged opposite to the wafer loading device 300. For example, the wafer grinding piece 100 is a wafer grinding pad, a wafer polishing pad or a wafer grinding wheel, etc., which is not limited in the present application. The wafer loading device 300 is used to load the wafer 2000, and the loaded wafer 2000 can be opposite to the wafer grinding piece 100. One of the grinding piece loading device 200 and the wafer loading device 300 is a rotating piece. That is, the grinding piece loading device 200 can drive the wafer grinding piece 100 to rotate, and the wafer loading device 300 and the wafer 2000 remain stationary. Alternatively, the wafer loading device 300 can drive the wafer 2000 to rotate, and the grinding piece loading device 200 and the wafer grinding piece 100 remain stationary. Thus, the wafer grinding piece 100 can perform fine grinding, rough grinding or polishing on the wafer 2000 .

[0048] In order to ensure a good grinding or polishing effect on the wafer 2000, the grinding device 1000 needs to maintain a stable grinding speed or polishing speed. It can be understood that the wafer grinding piece 100 is an important factor affecting the grinding or polishing effect of the grinding device 1000. Some existing grinding devices 1000 adjust the grinding speed of the wafer grinding piece 100 by adjusting the rotation speed of the wafer loading device 300 or the grinding piece loading device 200. However, this method can only adjust the grinding speed of the entire grinding surface of the wafer grinding piece 100 at the same time, and cannot adjust the abrasive dissolution rate of a local area on the wafer grinding piece 100. For example, the dissolution rate of the abrasive in some areas of the wafer grinding piece 100 is slow, which causes stress concentration problems in the wafer grinding piece 100, affecting the grinding effect.

[0049] Therefore, the embodiment of the present application provides a wafer grinding piece 100 with improved materials, which can achieve fine adjustment of the abrasive dissolution rate in a local area of ​​the wafer grinding piece 100. Figure 2 The wafer grinding piece 100 of the embodiment of the present application is shown as a three-dimensional structure of a wafer grinding pad. Figure 3 FIG. 1 shows a cross section of a wafer polishing pad of the wafer polishing member 100 according to an embodiment of the present application. Figure 2 and Figure 3 The wafer grinding piece 100 of the embodiment of the present application includes a substrate 1 and an abrasive layer 2, wherein the substrate 1 has a first surface 11, and the abrasive layer 2 is disposed on the first surface 11 of the substrate 1. The substrate 1 serves as a support layer for the abrasive layer 2. The substrate 1 may be flexible or rigid, and the present application does not limit this.

[0050] Furthermore, the substrate 1 can be made of a variety of materials. For example, the flexible substrate can include any one or more of a polymer film, cloth or paper, and the present application does not limit this. Among them, the polymer film can be a polyolefin film (such as polypropylene), a polyester film (such as polyethylene terephthalate), a polyamide film or a cellulose ester film, etc. Furthermore, the flexible substrate can be used in a wafer grinding pad or a wafer polishing pad.

[0051] The rigid substrate can be used in a wafer grinding wheel. As an example, the rigid substrate can include any one or more of a metal plate, a ceramic plate or other similar materials, and the present application does not limit this.

[0052] Continue to refer to Figure 3 The abrasive layer 2 on the substrate 1 of the embodiment of the present application includes a first adhesive 21, a first abrasive 22 and a photodegradable photosensitive agent 23. The first abrasive 22 and the photodegradable photosensitive agent 23 are dispersed in the first adhesive 21 and bonded by the first adhesive 21 to form an integrated film layer structure.

[0053] Compared with the existing wafer grinding piece 100, the wafer grinding piece 100 of the embodiment of the present application is additionally provided with a photodecomposable photosensitive agent 23. The photodecomposable photosensitive agent 23 requires multiple light emitting devices 400 to be added to the grinding device 1000 to work with the wafer grinding piece 100. The grinding device 1000 is further described below in conjunction with a specific embodiment.

[0054] Figure 4 The grinding device 1000 of the embodiment of the present application is a structure of a wafer thinning machine 1000a. Figure 4 and Figure 5The wafer thinning machine 1000a includes a workbench 300a, a plurality of rotating shafts 200a, a plurality of wafer grinding wheels 100a and a plurality of light emitting devices 400. The workbench 300a includes a plurality of clamping devices 301 and a positioning device (not shown in the figure), wherein the plurality of clamping devices 301 are used to fix the wafer 2000, and the positioning device is used to ensure the positioning accuracy of the wafer 2000 on the clamping device 301. The plurality of rotating shafts 200a are installed above the workbench 300a. The plurality of wafer grinding wheels 100a are respectively installed below the plurality of rotating shafts 200a. The first abrasive 22 in the plurality of wafer grinding wheels 100a has different particle sizes, and can be respectively used for rough grinding, fine grinding and polishing of the wafer 2000. One of the plurality of wafer grinding wheels 100a is a first wafer grinding wheel 101. The first wafer grinding wheel 101 can be used for polishing the wafer 2000.

[0055] by Figure 4 and Figure 5 The first wafer grinding wheel 101 among the multiple wafer grinding wheels 100a shown adopts the structure of the above-mentioned wafer grinding piece 100 as an example, that is, the abrasive layer 2 in the first wafer grinding wheel 101 includes a photodecomposable photosensitive agent 23. Multiple light-emitting devices 400 are installed on the workbench 300a at positions that can be opposite to the first wafer grinding wheel 101. The multiple light-emitting devices 400 correspond to different areas of the abrasive layer 2 on the first wafer grinding wheel 101. When the light beam emitted by the light-emitting device 400 irradiates the photodecomposable photosensitive agent 23 in the abrasive layer 2, the chemical bonds of the photodecomposable photosensitive agent 23 are broken.

[0056] When the wafer thinning machine 1000a is working, the first wafer grinding wheel 101 is controlled to contact the wafer 2000, and the rotating shaft 200a is controlled to drive the wafer grinding wheel 100a to rotate. Thus, the first wafer grinding wheel 101 can polish the wafer 2000. When it is necessary to increase the dissolution rate of the first abrasive 22 on certain areas corresponding to the wafer 2000 in the first wafer grinding wheel 101, the light emitting device 400 corresponding to the area can be turned on. The light beam emitted by the light emitting device 400 can break the chemical bonds of the photodegradable photosensitive agent 23 of the abrasive layer 2 in the area of ​​the first wafer grinding wheel 101, and the photodegradable photosensitive agent 23 is decomposed, so that the dissolution rate of the first abrasive 22 in the area is accelerated. Therefore, by controlling the opening and closing of multiple light emitting devices 400, the dissolution rate of the first abrasive 22 in different areas on the first wafer grinding wheel 101 can be accurately controlled. Thus, the dissolution rate of the first abrasive 22 in different regions of the first wafer grinding wheel 101 can be kept stable, so that the polishing rate of the wafer thinning machine 1000a is stable. At the same time, the stress concentration problem during the grinding process is reduced, and the grinding uniformity of the first abrasive 22 in the first wafer grinding wheel 101 is improved.

[0057] Furthermore, it is understandable that the light-emitting device 400 needs to be selected according to the material of the photodecomposable photosensitive agent 23. In some embodiments of the present application, the above-mentioned photodecomposable photosensitive agent 23 includes any one of a dichromate compound, a diazonium salt compound, a silver salt, or an alkali-soluble resin having an alkylene oxide group. These materials have the advantages of high resolution, good step coverage, and good contrast. Therefore, when the material of the photodecomposable photosensitive agent 23 is a silver salt or an alkali-soluble resin having an alkylene oxide group, the material can react with an infrared beam. Therefore, the light-emitting device 400 uses an infrared lamp. For another example, when the material of the photodecomposable photosensitive agent 23 is a dichromate compound or a diazonium salt compound (such as diazonaphthoquinone), the material can react with an ultraviolet beam. Therefore, the light-emitting device 400 uses an ultraviolet lamp.

[0058] As for other components in the abrasive layer 2, in some embodiments of the present application, the first abrasive 22 in the abrasive layer 2 may include any one or more of silicon oxide SiO2, cerium oxide CeO2, aluminum oxide Al2O3 or diamond powder. In addition, the abrasive layer 2 may also include other components. The first abrasive 22 may be matched with other components to grind different wafer 2000 materials, such as grinding or polishing wafers 2000 made of silicon oxide, polysilicon, metal tungsten, metal copper and the like.

[0059] Furthermore, in some embodiments of the present application, the first binder 21 in the abrasive layer 2 may include epoxy resin or acrylate. Furthermore, the first binder 21 may also include fillers, such as a mixture of nano-scale fillers and micro-scale fillers, or nano-scale fillers.

[0060] The above describes the materials of various components in the abrasive layer 2. In some embodiments, the wafer thinning machine 1000a further includes: Figure 6 The polishing liquid supply device 500 shown is used to supply polishing liquid. The polishing liquid may contain abrasive particles, oxidants, complexing agents, surfactants, abrasives, pH regulators, corrosion inhibitors and other components. Various components in the polishing liquid can react with the wafer 2000 to form a thin fluid film with weak bonding force on the surface to be processed of the wafer 2000. The abrasive particles in the fluid film and the polishing liquid can remove a small amount of the surface of the wafer 2000 under pressure and friction. Therefore, during the process of the first wafer grinding wheel 101 grinding or polishing the wafer 2000, the polishing liquid supply device 500 is controlled to spray the polishing liquid onto the first wafer grinding wheel 101 to optimize the polishing effect. At the same time, the polishing liquid can also take away the first abrasive 22 ground out of the abrasive layer 2 in the first wafer grinding wheel 101.

[0061] Therefore, in order to assist the polishing liquid to timely guide out the first abrasive 22 after grinding the wafer 2000, in some embodiments of the present application, the abrasive layer 2 in the first wafer grinding wheel 101 is formed as follows: Figure 7 The plurality of guide grooves 3 shown are arranged at intervals. The plurality of guide grooves 3 may also intersect in a local area. Figure 8 As shown, the guide grooves 3 can extend from the inside to the outside of the abrasive layer 2. Therefore, the plurality of guide grooves 3 can accelerate the discharge of the first abrasive 22 after grinding the wafer 2000, thereby improving the grinding uniformity.

[0062] However, during the grinding or polishing process, the groove wall of the guide groove 3 is irradiated by the light beam, and the dissolution speed is fast and it is easy to break. Fig. 9 , the groove wall of the guide groove 3 in the embodiment of the present application is covered with a first light shielding layer 4a. The light beam emitted by the light emitting device 400 is blocked by the first light shielding layer 4a and will not be irradiated on the groove wall of the guide groove 3, and the groove wall of the guide groove 3 will not be accelerated to dissolve and break. Thus, the side wall of the guide groove 3 is prevented from dissolving too fast and breaking.

[0063] Furthermore, the bottom of the guide groove 3 does not need to be ground or polished for the wafer 2000, so in some embodiments of the present application, such as Fig.10 As shown, the bottom of the guide groove 3 is also covered with a second light shielding layer 4b. The light beam emitted by the light emitting device 400 is blocked by the second light shielding layer 4b and will not be irradiated on the bottom of the guide groove 3, and the bottom of the guide groove 3 will not be accelerated to dissolve.

[0064] It should be noted that the first light shielding layer 4a and the second light shielding layer 4b of the guide groove 3 can be made by the same process to save the process flow. Therefore, the first light shielding layer 4a and the second light shielding layer 4b of the guide groove 3 can be made of the same material. Of course, the first light shielding layer 4a and the second light shielding layer 4b of the guide groove 3 can also be made of different materials, and this application does not limit this.

[0065] In some embodiments of the present application, the first light shielding layer 4a and the second light shielding layer 4b of the above-mentioned guide groove 3 may both include carbon powder to achieve light-proof performance. In addition, the first light shielding layer 4a also includes a second abrasive, for example, the second abrasive is any one or several of silicon oxide, cerium oxide, aluminum oxide or diamond powder, so that the first light shielding layer 4a can also grind the wafer 2000 at the same time, maintaining the same grinding speed as the groove wall of the guide groove 3. In addition, the second light shielding layer 4b can also include any one or several abrasive materials of silicon oxide, cerium oxide, aluminum oxide or diamond powder. In addition, the first light shielding layer 4a and the second light shielding layer 4b of the guide groove 3 also include a second adhesive, and the second abrasive and carbon powder are dispersed in the second adhesive. The second adhesive can bond the carbon powder and the second abrasive together.

[0066] The above description is made by taking the example that the grinding device 1000 of the embodiment of the present application is a wafer thinning machine 1000a. Fig.11 The structure of the grinding device 1000 of the embodiment of the present application is also shown as a chemical mechanical polisher. Fig.11 The chemical mechanical polishing machine 1000b includes a rotating disk 200b, a wafer holder 300b, a wafer grinding pad 100b and a plurality of light emitting devices 400, wherein the rotating disk 200b is located directly below the wafer holder 300b. The wafer holder 300b is used to fix the wafer 2000, and the wafer grinding pad 100b is fixed on the upper surface of the rotating disk 200b. The abrasive layer 2 in the wafer grinding pad 100b can be made of the same structure and material as the abrasive layer 2 in the first wafer grinding wheel 101 in the above-mentioned embodiment. The plurality of light emitting devices 400 correspond to different areas of the abrasive layer 2 on the wafer grinding pad 100b, respectively. When the light beam emitted by the light emitting device 400 irradiates the photodecomposable photosensitive agent 23 in the abrasive layer 2, the chemical bonds in the photodecomposable photosensitive agent 23 are broken.

[0067] Furthermore, the chemical mechanical polishing machine 1000b further includes: Fig.12 The slurry arm 500b is shown in the figure. The slurry arm 500b is arranged above the rotating disk 200b. The slurry arm 500b can be a hollow structure. The polishing liquid can be guided to the wafer polishing pad 100b through the pipeline inside the slurry arm 500b. Fig.12 and Fig.13 As shown, a plurality of light emitting devices 400 may be fixed on the polishing slurry arm 500b and arranged in sequence along the extending direction of the polishing slurry arm 500b.

[0068] When the chemical mechanical polisher 1000b is working, the wafer 2000 is controlled to contact with the wafer polishing pad 100b, and the rotating disk 200b is controlled to drive the wafer polishing pad 100b to rotate. Thus, the wafer polishing pad 100b can polish the wafer 2000. Similarly, when it is necessary to increase the dissolution rate of the first abrasive 22 on certain areas corresponding to the wafer 2000 in the wafer polishing pad 100b, the light emitting device 400 corresponding to the area can be turned on. The light beam emitted by the light emitting device 400 can break the chemical bonds of the photodegradable photosensitive agent 23 of the abrasive layer 2 in the area of ​​the wafer polishing pad 100b, and the photodegradable photosensitive agent 23 is decomposed, so that the dissolution rate of the first abrasive 22 in the area is accelerated. Therefore, the chemical mechanical polisher 1000b of the embodiment of the present application can accurately control the dissolution rate of the first abrasive 22 in different areas of the wafer polishing pad 100b by controlling the opening and closing of multiple light-emitting devices 400, and can achieve the dissolution rate of the first abrasive 22 in different areas of the wafer polishing pad 100b to remain stable, so that the polishing rate is stable. At the same time, the stress concentration problem in the grinding process is reduced, and the grinding uniformity of the first abrasive 22 in the wafer polishing pad 100b is improved.

[0069] The above mainly describes the structure and materials of the wafer grinding piece 100 and the grinding device 1000. In order to realize the manufacturing of the above-mentioned wafer grinding piece 100, the embodiment of the present application also includes a manufacturing process of the wafer grinding piece, and the manufacturing process includes the following steps:

[0070] S100 : mixing the first binder 21 , the first abrasive 22 and the photodegradable photosensitizer 23 to obtain a mixed solution 24 .

[0071] For example, the first abrasive 22, the photodegradable photosensitive agent 23 and the binder (liquid) are poured into Fig.14 The mixing device 3000 shown is used for mixing and stirring, so that the first abrasive 22 and the photodecomposable photosensitive agent 23 are uniformly dispersed in the first binder 21 (liquid).

[0072] S200 : coating the mixed liquid 24 on the substrate 1 to form an abrasive layer 2 .

[0073] For example, Fig.15 The structure of a wafer grinding piece processing equipment is shown. Fig.15 As shown, the grinding processing equipment 4000 includes an unwinding drum 10, a transmission workbench 20 and a first coating device 30. A multi-layer substrate 1 is wound on the unwinding drum 10, and a substrate 1 is transmitted on the transmission workbench 20. The nozzle of the first coating device 30 is directed toward the substrate 1 on the transmission workbench 20. The first coating device 30 can coat the mixed liquid on the substrate 1 on the transmission workbench 20.

[0074] S400: curing the abrasive layer 2.

[0075] For example, Fig.15 As shown, the grinding processing equipment 4000 further includes an abrasive layer curing device 40, which can be a heating device or an ultraviolet lamp curing device. It should be noted that the abrasive layer curing device 40 can only be an ultraviolet lamp curing device when the photosensitive spectrum of the photodecomposable photosensitive agent 23 is not an ultraviolet spectrum.

[0076] Based on this, in some embodiments of the present application, between S200 and S400, the following is further included:

[0077] S300 : forming a plurality of guide grooves 3 on the abrasive layer 2 .

[0078] For example, continue to refer to Fig.15 The above-mentioned grinding processing equipment 4000 further includes a pattern printing roller 50, on which a pattern of a plurality of guide grooves 3 is formed. Thus, the pattern of a plurality of guide grooves 3 can be formed by pressing the printing roller on the abrasive layer 2. Thus, a wafer grinding piece 100 having guide grooves 3 is manufactured, such as Fig.16 shown.

[0079] Furthermore, in some embodiments, after the above S400, the manufacturing method further includes:

[0080] S500 : forming a light shielding layer 4 on a surface of the abrasive layer 2 away from the substrate 1 .

[0081] For example, Fig.15 As shown, the above-mentioned grinding processing equipment 4000 further includes a second coating device 60, and the opening of the second coating device 60 is also facing the transmission workbench 20. The second coating device 60 can coat the light shielding material on the substrate 1 with the abrasive layer 2 on the transmission workbench 20. Thus, the light shielding layer 4 is formed on the surface of the entire abrasive layer 2 away from the substrate 1, as shown in FIG. Fig.17 shown.

[0082] S600: Curing the light shielding layer 4.

[0083] For example, Fig.15 As shown, the above-mentioned grinding processing equipment 4000 further includes a light shielding layer curing device 70, which can be a heating device or an ultraviolet lamp curing device to cure the light shielding layer 4. Then, the wafer grinding piece roll is obtained through the winding device.

[0084] S700: removing the light shielding layer 4 on the abrasive layer 2 except for the surface of the guide groove 3 .

[0085] For example, the embodiment of the present application can use a grinding device to remove the light shielding layer 4 on the abrasive layer 2 except the surface of the guide groove 3. Thus, a wafer grinding piece with a guide groove 3 having a light shielding layer 4 on the groove wall and the groove bottom is formed, such as Fig.18 shown.

[0086] It should be noted that the wafer grinding piece roll can be cut according to the shape of the required wafer grinding piece 100. Afterwards, after the cut wafer grinding piece is installed in the grinding equipment, the S700 process is performed to obtain the required wafer grinding piece 100.

[0087] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A wafer grinding piece, characterized in that: include: substrate; An abrasive layer is disposed on the substrate; the abrasive layer comprises a first abrasive, a photodecomposable photosensitizer and a first adhesive, wherein the first abrasive and the photodecomposable photosensitizer are dispersed in the first adhesive and bonded by the first adhesive.

2. The wafer grinding piece according to claim 1, characterized in that: The photodecomposable photosensitizer includes any one of dichromate compounds, diazonium salt compounds, silver salts or alkali-soluble resins having alkylene oxide groups.

3. The wafer grinding piece according to claim 1 or 2, characterized in that: A plurality of guide grooves are formed on a surface of the abrasive layer away from the substrate, and the plurality of guide grooves are distributed at intervals; the guide grooves extend from the inside of the abrasive layer to the outside.

4. The wafer grinding piece according to claim 3, characterized in that: The groove wall of the guide groove is covered with a light shielding layer.

5. The wafer grinding piece according to claim 3 or 4, characterized in that: The bottom of the guide groove is covered with a light-shielding layer.

6. The wafer grinding piece according to claim 4 or 5, characterized in that: The light shielding layer includes a second abrasive, carbon powder and a second binder. The second abrasive and the carbon powder are dispersed in the second binder and bonded by the second binder.

7. A method for manufacturing a wafer grinding piece, characterized in that: The following steps are involved: Mixing a first binder, a first abrasive and a photodegradable photosensitizer to obtain a mixed solution; coating the mixed solution on a substrate to form an abrasive layer; The abrasive layer is cured.

8. The method for manufacturing a wafer grinding piece according to claim 7, characterized in that: Between coating the mixed solution on a substrate to form an abrasive layer and curing the abrasive layer, the method further comprises: A plurality of guide grooves are formed on the abrasive layer.

9. The method for manufacturing a wafer grinding piece according to claim 8, characterized in that: After curing the abrasive layer, the method further comprises: forming a light shielding layer on a surface of the abrasive layer away from the substrate; curing the light-shielding layer; The light shielding layer on the abrasive layer in areas other than the groove surface of the guide groove is removed.

10. A grinding device, characterized in that: include: Abrasive parts loading device; The wafer grinding piece according to any one of claims 1 to 6, wherein the wafer grinding piece is arranged on the grinding piece loading device; A wafer loading device, wherein the wafer on the wafer loading device is arranged opposite to the wafer grinding piece; the wafer loading device is used to drive the wafer to rotate or the grinding piece loading device is used to drive the wafer grinding piece to rotate; A plurality of light emitting devices are respectively arranged opposite to a plurality of regions of the grinding layer in the wafer grinding piece, and the plurality of light emitting devices are used to control the dissolution rate of the photodecomposable photosensitizer in the wafer grinding piece.

11. The grinding device according to claim 10, characterized in that The photodecomposable photosensitizer is a dichromate compound or a diazonium salt compound, and the light-emitting device is an ultraviolet lamp; or, the photodecomposable photosensitizer is a silver salt or an alkali-soluble resin having an alkylene oxide group, and the light-emitting device is an infrared lamp.

12. The grinding device according to claim 10 or 11, characterized in that: The grinding equipment is a chemical mechanical polisher or a wafer thinning machine.

13. A method for processing a wafer using the grinding device according to any one of claims 10 to 12, characterized in that: The following steps are involved: loading a wafer onto a wafer loading device; Controlling a wafer grinding piece on a grinding piece loading device to contact with a wafer on the wafer loading device; Controlling the wafer grinding piece on the grinding piece loading device or the wafer on the wafer loading device to rotate so as to grind the wafer; The opening and closing of the plurality of light emitting devices are controlled respectively to adjust the dissolution rate of the photodecomposable photosensitizer in the wafer grinding piece.

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