CN-116810659-B - Preparation method of metal-bonded diamond porous semiconductor thinning grinding wheel

CN116810659BCN 116810659 BCN116810659 BCN 116810659BCN-116810659-B

Abstract

The invention belongs to the technical field of abrasive grinding tools, and particularly relates to a preparation method of a metal-bonded diamond porous semiconductor thinning grinding wheel; the preparation method comprises the steps of preparing materials of an abrasive layer, forming blocks, sintering and processing the blocks, bonding or welding the blocks and a matrix, and obtaining the porous high-strength metal-bonded diamond thinning grinding wheel after post-processing treatment. The method comprises the steps of adopting original hydrogen to reduce and presintered metal binding abrasive, optimally selecting metal binding agent and pore-forming agent, performing mechanical pressing molding on the prepared material, sintering the material in a vacuum furnace at 600-900 ℃, bonding or welding a matrix, and performing mechanical processing post-treatment to obtain the porous high-strength metal binding agent diamond grinding wheel. The performance of the grinding wheel in the application of semiconductor thinning such as SiC wafer thinning, sapphire thinning and monocrystalline silicon thinning exceeds the service performance of the existing grinding wheel.

Inventors

SONG YUNFEI
CHENG JUAN
LI WEIFENG
LIU WEICHAO
ZHANG FENG
DING CHUNSHENG
CHEN YACHAO
ZHAO BIN
LIU ZHENXING
YAO YU

Assignees

郑州海科研磨工具有限公司

Dates

Publication Date: 20260512
Application Date: 20230718

Claims (2)

1. The preparation method of the metal-bonded diamond porous semiconductor thinning grinding wheel is characterized by comprising the following steps of: Preparing a presintered abrasive material, namely adding 5-25% by volume of the cavity of a fixed die forming die into the presintered abrasive material, adding 20-60% by volume of metal bonding agent into the presintered abrasive material, adding 20-60% by volume of pore-forming agent into the presintered abrasive material, and adding a temporary bonding agent into the presintered abrasive material by 0.05% by mass of the metal bonding agent, mixing the presintered abrasive material with the temporary bonding agent in a V-type mixer for 0.5-3 h, adding the metal bonding agent and the pore-forming agent, continuously mixing for 1-2 h, and sieving for later use; The preparation method of the presintered abrasive comprises the steps of fully mixing a diamond abrasive with metal powder by means of an organic adhesive phenolic resin liquid, wherein the diamond abrasive is 80% -90% of the total raw material mass, the metal powder is 10% -20% of the total raw material mass, the phenolic resin liquid is additionally added by 5% of the total raw material mass, the uniformly mixed materials are formed into a green body through pressing by a hydraulic press, the pressure is 10-30 MPa, the green body is cured for 1-3 hours at 180 ℃ in a curing furnace, the cured green body is preserved for 1-3 hours at 300 ℃ by means of a hydrogen reduction furnace, and the presintered abrasive is obtained after ball milling and sieving after cooling along with the furnace, the diamond abrasive is any one of diamond, nickel-plated diamond and titanium-plated diamond or any kind of diamond, the metal powder is a copper powder and tin powder mixture, and the ratio of copper powder to tin powder is 1-2:1; the metal bonding agent comprises 0% -40% of copper-tin alloy powder, 30% -80% of copper powder, 1% -40% of tin powder, 0% -10% of silver powder, 0% -10% of lead powder and 0% -10% of nickel powder, wherein the pore-forming agent comprises one or more of PMMA, sodium chloride, ammonium bicarbonate and urea mixed with titanium hydride or nickel hydride; Step two, agglomeration molding, namely pouring the spare abrasive layer material into a mold, placing the mold on a hydraulic press for machine press molding, and demolding to obtain an agglomerated semi-finished product; Step three, sintering and treating the caking, namely placing the semi-finished product of the caking into a vacuum sintering furnace for sintering, cooling along with the furnace to obtain the caking, and placing the caking into a water bath for cleaning and fully drying for standby; Step four, connecting the caking with the matrix, namely solidifying and bonding the caking with the matrix through an organic adhesive or brazing and welding; and fifthly, post-processing to obtain the qualified grinding wheel with the grinding material layer tightly combined with the matrix.
2. The method for preparing the metal-bonded diamond porous semiconductor thinning grinding wheel is characterized by comprising the steps of placing a semi-finished product of agglomeration into a vacuum sintering furnace, sintering at 600-900 ℃, keeping the temperature for 10-120 min, cooling along with the furnace to obtain agglomeration, placing the agglomeration into a water bath, introducing flowing distilled water with the constant temperature of 90 ℃ for cleaning for 1-3 h, and fully drying for later use.

Description

Preparation method of metal-bonded diamond porous semiconductor thinning grinding wheel Technical Field The invention belongs to the technical field of abrasive grinding tools, and particularly relates to a preparation method of a metal-bonded diamond porous semiconductor thinning grinding wheel. Background Along with the rapid development of material science and technology, novel materials are widely applied in engineering, wherein the novel materials comprise difficult-to-process materials with high hardness, high brittleness and easy burn, such as monocrystalline silicon carbide wafers, monocrystalline silicon wafers and other semiconductor materials, the wafer thinning grinding wheel plays an important role in the chip preparation process, firstly, the whole thickness of the chip can be reduced through a thinning process, heat dissipation and integration are facilitated, and secondly, the thickness and the surface roughness of a damaged layer of the surface of the wafer are reduced, the internal stress caused by each procedure before thinning is released, and the degree of collapse of a single chip in the dicing process is reduced. However, in the grinding process using semiconductor materials such as silicon carbide and silicon, the resin bond (mainly phenolic resin) is used as a common grinding wheel bonding material, which is not suitable for a diamond grinding tool with superfine granularity, on the one hand, heat generated by grinding is not easy to dissipate due to poor heat conduction of the resin material, on the other hand, the holding force of the resin bond on the diamond is lower, and when the granularity of the diamond is finer, the diamond grinding wheel with the resin bond needs a more compact structure to ensure certain holding force on the diamond, but the porosity of the grinding wheel is reduced, and the abrasion ratio is increased. Therefore, in order to truly solve the problem of difficult processing of the novel material, the bottleneck of the traditional processing technology is broken through, and the key is to develop a novel processing tool and a novel material. Disclosure of Invention The invention aims to provide a preparation method of a metal-bonded diamond porous semiconductor thinning grinding wheel, which aims to solve the defects of difficult dressing and sharpening of a traditional compact metal-bonded diamond grinding wheel, and in addition, the invention aims to solve the problems of dressing and self sharpening of the metal-bonded diamond grinding wheel by improving the porosity of the metal-bonded grinding wheel, improve the holding capacity of a bonding agent on the grinding wheel by a unique grinding material presintering technology, improve the strength of the grinding wheel and prolong the service life of the grinding wheel. In order to achieve the above purpose, the present invention adopts the following technical scheme: The preparation method of the metal-bonded diamond porous semiconductor thinning grinding wheel comprises the following steps: step one, preparing an abrasive layer material, namely preparing a presintered abrasive, uniformly mixing the presintered abrasive, a metal bonding agent, a pore-forming agent and a temporary bonding agent in a three-dimensional mixer, and sieving for later use; Step two, agglomeration molding, namely pouring the spare abrasive layer material into a mold, placing the mold on a hydraulic press for machine press molding, and demolding to obtain an agglomerated semi-finished product; Step three, sintering and treating the caking, namely placing the semi-finished product of the caking into a vacuum sintering furnace for sintering, cooling along with the furnace to obtain the caking, and placing the caking into a water bath for cleaning and fully drying for standby; Step four, connecting the caking with the matrix, namely solidifying and bonding the caking with the matrix through an organic adhesive or brazing and welding; and fifthly, post-processing to obtain the qualified grinding wheel with the grinding material layer tightly combined with the matrix. Further, the pre-sintered abrasive is prepared as follows: The method comprises the steps of fully mixing diamond abrasive materials with the aid of an organic adhesive phenolic resin liquid and metal powder, wherein the diamond abrasive materials are 80% -90% of the total raw material mass, the metal powder is 10% -20% of the total raw material mass, the phenolic resin liquid is additionally added in an amount which is 5% of the total raw material mass, the uniformly mixed materials are pressed into a green body by a hydraulic press, the pressure is 10-30 MPa, the green body is cured for 1-3 hours at 180 ℃ in a curing furnace, the cured green body is kept at 300 ℃ for 1-3 hours by a hydrogen reduction furnace, and the pre-sintered abrasive materials are obtained after ball milling and sieving after cooling along with the furnace. Preferably, the diamond abrasive is any o