阅读说明：本技术 倒角磨轮及其制备方法、晶圆加工设备 (Chamfer grinding wheel, preparation method thereof and wafer processing equipment ) 是由 李亮亮 于 2019-09-27 设计创作，主要内容包括：本发明提供了一种倒角磨轮及其制备方法、晶圆加工设备,属于半导体技术领域。倒角磨轮的制备方法,包括：提供预设粒径的多个金刚石颗粒,在所述多个金刚石颗粒的表面形成金属涂层；将表面形成有金属涂层的金刚石颗粒与粘合剂混合,得到混合物；提供磨轮本体,所述磨轮本体的外周面上设置有至少两个沿所述磨轮本体的周向设置的凹槽；将所述混合物填充到所述凹槽内,在真空高温环境中控制所述混合物固化；对固化后的所述混合物进行形状修正,形成研磨槽。本发明能够有效提高金刚石与倒角磨轮本体的结合强度,进而提高硅片边缘研磨或抛光加工质量。(The invention provides a chamfer grinding wheel, a preparation method thereof and wafer processing equipment, and belongs to the technical field of semiconductors. The preparation method of the chamfer grinding wheel comprises the following steps: providing a plurality of diamond particles with a preset particle size, and forming a metal coating on the surfaces of the plurality of diamond particles; mixing the diamond particles with the metal coating formed on the surface with a binder to obtain a mixture; providing a grinding wheel body, wherein at least two grooves arranged along the circumferential direction of the grinding wheel body are formed in the peripheral surface of the grinding wheel body; filling the mixture into the groove, and controlling the mixture to be solidified in a vacuum high-temperature environment; and correcting the shape of the solidified mixture to form a grinding groove. The invention can effectively improve the bonding strength of the diamond and the chamfer angle grinding wheel body, thereby improving the grinding or polishing processing quality of the silicon wafer edge.)

1. A method for preparing a chamfer grinding wheel is characterized by comprising the following steps:

providing a plurality of diamond particles with a preset particle size, and forming a metal coating on the surfaces of the plurality of diamond particles;

mixing the diamond particles with the metal coating formed on the surface with a binder to obtain a mixture;

providing a grinding wheel body, wherein at least two grooves arranged along the circumferential direction of the grinding wheel body are formed in the peripheral surface of the grinding wheel body;

filling the mixture into the groove, and controlling the mixture to be solidified in a vacuum high-temperature environment;

and correcting the shape of the solidified mixture to form a grinding groove.

2. The method for preparing a chamfer grinding wheel according to claim 1, wherein the metal coating is titanium or nickel or silver.

3. The method of manufacturing a chamfer grinding wheel according to claim 2, wherein forming a metal coating on the surface of the plurality of diamond particles comprises:

and depositing a Ti or Ni layer on the surface of the diamond particles by using a dual-glow plasma surface metallurgy DGPSA process.

4. The method for preparing the chamfering grinding wheel according to claim 3, wherein in the DGPSA process, the source electrode adopts a filiform target material, the deposition temperature is 700-900 ℃, the deposition pressure is 30-40Pa, and the protective gas is argon.

5. The method for manufacturing a chamfering grinding wheel according to claim 4, wherein the wire-shaped target material is manufactured by uniformly fixing Ti or Ni wires having a purity of 99.999% on a stainless steel plate, the size of the Ti or Ni wires is Φ 3.5mm 20mm, and the size of the stainless steel plate is 55mm 3.0 mm.

6. The method of manufacturing a chamfer grinding wheel according to claim 2, wherein the forming a metal coating on the surface of the plurality of diamond particles comprises:

and depositing an Ag layer on the surface of the diamond particles by utilizing a magnetron sputtering process.

7. The method for preparing the chamfer grinding wheel according to claim 6, wherein in the magnetron sputtering process, the target material is an Ag plate with the purity of 99.999%, the size of the Ag plate is 55mm x 3.0mm, the deposition temperature is 300-700 ℃, the deposition pressure is 0.5-2Pa, and the protective gas is argon.

8. The method of manufacturing a chamfer grinding wheel according to claim 1, wherein the controlling the solidification of the mixture in a vacuum high temperature environment comprises:

and placing the grinding wheel body filled with the mixture into a vacuum welding furnace, and keeping the set temperature for a set time to solidify the mixture.

9. The method of manufacturing a chamfered grinding wheel according to claim 1, wherein the thickness of the metal coating layer is 0.8 to 1.5 μm.

10. A chamfered grinding wheel produced by the method of any one of claims 1 to 9.

11. A wafer processing apparatus comprising the chamfer grinding wheel of claim 10.

Technical Field

The invention relates to the technical field of semiconductors, in particular to a chamfering grinding wheel, a preparation method thereof and wafer processing equipment.

Background

Wafers (wafers), the most basic material in the semiconductor field, can be fabricated into various circuit device structures, and become integrated circuit products with specific electrical functions. The wafer is processed and formed for many times through crystal growth (Growing), Slicing (Slicing), chamfering (Edge Grinding), Grinding (Lapping), Polishing (Polishing), Cleaning (Cleaning) and the like, and finally the surface which meets the requirements of flatness and roughness is obtained. In the wafer production process, the edge treatment of the silicon wafer is important, the edge small cracks or cracks on the edge can generate mechanical stress on the silicon wafer, so that dislocation is generated, harmful contamination accumulation and shedding are caused, in addition, the edge dislocation can also cause the edge dislocation growth in high-temperature treatment or surface epitaxy, and the excellent chamfering process can ensure that the edge of the silicon wafer obtains a smooth radius contour, and the influence is reduced to the minimum.

Diamond is often used to machine edge chamfers of ground or polished silicon wafers because of its superior properties of highest hardness. At present, a diamond coating in a monocrystalline silicon wafer chamfering grinding wheel is prepared by adding an adhesive and bonding diamond particles on the inner wall of a grinding groove in a high-temperature environment, but because diamond has high interfacial energy and chemical inertness, the bonding performance of the diamond coating of the existing chamfering grinding wheel is poor, and under the action of huge mechanical shearing force brought by high-speed rotation, the diamond particles are easily stripped and fall off, and the surface of a wafer is scratched, so that huge defects are caused.

Disclosure of Invention

The invention aims to provide a chamfering grinding wheel, a preparation method thereof and wafer processing equipment, which can effectively improve the bonding strength of diamond and the chamfering grinding wheel, and further improve the grinding or polishing processing quality of the edge of a silicon wafer.

To solve the above technical problem, embodiments of the present invention provide the following technical solutions:

in one aspect, an embodiment of the present invention provides a method for manufacturing a chamfered grinding wheel, including:

providing a plurality of diamond particles with a preset particle size, and forming a metal coating on the surfaces of the plurality of diamond particles;

mixing the diamond particles with the metal coating formed on the surface with a binder to obtain a mixture;

providing a grinding wheel body, wherein at least two grooves arranged along the circumferential direction of the grinding wheel body are formed in the peripheral surface of the grinding wheel body;

filling the mixture into the groove, and controlling the mixture to be solidified in a vacuum high-temperature environment;

and correcting the shape of the solidified mixture to form a grinding groove.

Optionally, the metal coating is titanium or nickel or silver.

Optionally, the forming a metal coating on the surface of the plurality of diamond particles comprises:

and depositing a Ti or Ni layer on the surface of the diamond particles by using a dual-glow plasma surface metallurgy DGPSA process.

Optionally, in the DGPSM process, the source is a filament target, the deposition temperature is 700-.

Optionally, the wire-shaped target is prepared by uniformly fixing Ti or Ni wires with the purity of 99.999% on a stainless steel plate, wherein the size of the Ti or Ni wires is phi 3.5mm by 20mm, and the size of the stainless steel plate is 55mm by 3.0 mm.

Optionally, the forming a metal coating on the surface of the plurality of diamond particles comprises:

and depositing an Ag layer on the surface of the diamond particles by utilizing a magnetron sputtering process.

Optionally, in the magnetron sputtering process, the target material is an Ag plate with a purity of 99.999%, the size of the Ag plate is 55mm x 3.0mm, the deposition temperature is 300-.

Optionally, the controlling the curing of the mixture in the vacuum high temperature environment comprises:

and placing the grinding wheel body filled with the mixture into a vacuum welding furnace, and keeping the set temperature for a set time to solidify the mixture.

Specifically, the thickness of the prepared metal coating is 0.8-1.5 μm.

The embodiment of the invention also provides a chamfer grinding wheel which is manufactured by adopting the preparation method.

The embodiment of the invention also provides wafer processing equipment which comprises the chamfer angle grinding wheel.

The embodiment of the invention has the following beneficial effects:

in the scheme, a layer of metal coating is prepared on the surface of the diamond particle, the metal coating can be selected from Ti, Ni and Ag metals with better activity and can also be selected from high-melting-point high-strength carbide metals such as W, Ta, when the metal coating is prepared on the surface of the diamond particle, the deposition reaction temperature is high, an element diffusion region exists between the metal coating and the diamond, and the carbide is formed, so that the bonding strength is high, the interface energy and chemical inertia of the diamond can be reduced due to the existence of the metal coating, the bonding and welding performance of the diamond particle is improved, the bonding strength of the diamond and a chamfer angle grinding wheel is effectively improved, the grinding or polishing processing quality of the edge of a silicon wafer is improved, and a foundation is provided for the quality extension; in addition, the existence of the metal coating can also improve the wear resistance of the diamond coating and prolong the service life of the chamfer grinding wheel; the selection of the adhesive between the chamfering grinding wheel and the diamond particles can be adjusted according to the performance of the metal coating, so that the selection range of the adhesive is effectively expanded, and the cost of the adhesive can be reduced.

Drawings

FIG. 1 is a schematic structural view of a conventional chamfer grinding wheel;

FIG. 2 is a schematic flow chart of a method of manufacturing a chamfer grinding wheel according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of a chamfer grinding wheel according to an embodiment of the present invention.

Reference numerals

1 chamfer grinding wheel matrix

2 grinding groove

3 Diamond particles

4 adhesive

5 Metal coating

Detailed Description

In order to make the technical problems, technical solutions and advantages to be solved by the embodiments of the present invention clearer, the following detailed description will be given with reference to the accompanying drawings and specific embodiments.

Fig. 1 is a schematic structural view of a conventional chamfer grinding wheel, and a method for manufacturing a diamond coating in the conventional chamfer grinding wheel includes: mixing the binder 4 with diamond particles 3 having a certain particle size; filling the mixed diamond particles 3 into a grinding groove 2 on a chamfer grinding wheel matrix 1; putting the chamfering grinding wheel into a high-temperature furnace, sintering, and combining the diamond particles 3 with the chamfering grinding wheel matrix 1; and finally, grinding wheel dressing is carried out to form the grinding groove with the required shape.

However, because diamond has high interfacial energy and chemical inertness, the diamond coating of the existing chamfer grinding wheel has poor bonding performance, and diamond particles are easy to peel off and fall off under the action of huge mechanical shearing force caused by high-speed rotation, so that the surface of a wafer is scratched, and huge defects are caused.

In order to solve the above problems, embodiments of the present invention provide a chamfering grinding wheel, a manufacturing method thereof, and a wafer processing apparatus, which can effectively improve the bonding strength between a diamond and the chamfering grinding wheel, and further improve the grinding or polishing quality of a silicon wafer edge.

An embodiment of the present invention provides a method for manufacturing a chamfer grinding wheel, as shown in fig. 2, including:

step 101: providing a plurality of diamond particles with a preset particle size, and forming a metal coating on the surfaces of the plurality of diamond particles;

specifically, the thickness of the metal coating layer can be controlled to be 0.8-1.5 μm;

step 102: mixing the diamond particles with the metal coating formed on the surface with a binder to obtain a mixture;

step 103: providing a grinding wheel body, wherein at least two grooves arranged along the circumferential direction of the grinding wheel body are formed in the peripheral surface of the grinding wheel body;

step 104: filling the mixture into the groove, and controlling the mixture to be solidified in a vacuum high-temperature environment;

step 105: and correcting the shape of the solidified mixture to form a grinding groove.

In the embodiment, a metal coating is prepared on the surface of diamond particles, the metal coating can be selected from Ti, Ni and Ag metals with better activity, and high-melting-point strong carbide metals such as W, Ta, when the metal coating is prepared on the surface of the diamond particles, the deposition reaction temperature is high, an element diffusion region exists between the metal coating and the diamond, and the carbide is formed, so that the bonding strength is high, the interface energy and chemical inertia of the diamond can be reduced due to the existence of the metal coating, the bonding and welding performance of the diamond particles is improved, the bonding strength of the diamond and a chamfer angle grinding wheel is effectively improved, the grinding or polishing processing quality of the edge of a silicon wafer is improved, and a foundation is provided for the quality extension of the wafer; in addition, the existence of the metal coating can also improve the wear resistance of the diamond coating and prolong the service life of the chamfer grinding wheel; the selection of the adhesive between the chamfering grinding wheel and the diamond particles can be adjusted according to the performance of the metal coating, so that the selection range of the adhesive is effectively expanded, and the cost of the adhesive can be reduced.

In a specific embodiment, the metal coating can adopt titanium or silver or nickel, the activity of the titanium, the silver and the nickel is better, and the metal coating is prepared on the surface of the diamond, so that the interface layer and the chemical inertness of diamond particles can be reduced, the bonding and welding performance of the diamond particles is improved, and the bonding strength of the diamond coating and the chamfer grinding wheel body is effectively improved. Of course, in the technical solution of the present invention, the metal coating is not limited to silver or nickel, and other metals with better activity may also be used. Furthermore, the metal coating is not limited to the metal with better activity, and the metal element can be formed by strong carbide, so that the wear resistance of the diamond coating can be improved by the metal coating and the carbide. A