Study On Pore Characteristics Of Fine-grained Diamond Grinding Wheel

The excellent physical properties and processing quality of semiconductor materials are the keys to the fabrication of high-performance devices.Monocrystalline silicon substrates with ultra-smooth,damage-free surfaces are widely used in the fabrication of microelectronic chips and sensors.Monocrystalline silicon has hard and brittle properties,and is a difficult-tomachine material.Ultra-precision grinding is one of the important processing methods.In the process of ultra-precision grinding of single crystal silicon substrates,vitrified-bonded diamond grinding wheels have the advantages of high grinding efficiency,good self-sharpening,not easy to block and burn workpieces,and are widely used.For surface grinding,the application of vitrified fine-grained diamond grinding wheels is increasing.However,in the process of ultraprecision grinding,in order to avoid clogging and burn the workpiece with the fine-grained diamond grinding wheel of vitrified bond,and to improve the heat dissipation of the grinding wheel and the effect of accommodating chips,the grinding wheel is required to have excellent porosity characteristics.Evaluating the porosity characteristics of porous vitrified bond finegrained diamond grinding wheels is the key to manufacturing high-performance grinding wheels and researching the grinding performance of grinding wheels,but there is currently a lack of research on the evaluation of porosity characteristics of grinding wheels.The porosity characteristics of the grinding wheel have been studied in depth.The main contents and conclusions of the paper are as follows:(1)The manufacturing formula of the grinding wheel was designed,and the diamond abrasive grain size of the porous ceramic bond fine-grained diamond grinding wheel formula was reasonably selected;based on the ceramic bond of the boro-aluminosilicate glass system,a small amount of alkali metal oxide was added.and alkaline earth metal oxides to adjust the properties of the binder;the effect of various pore-forming agents was discussed;the effect of different sintering temperatures on the pore characteristics of the grinding wheel surface was studied.The mass fractions of abrasive grains,vitrified binder and pore-forming agent in the final formulation of the grinding wheel were 45%,30%-40% and 5%-20%,respectively.(2)Based on digital image processing technology,a new method for characterizing porosity on the surface of grinding wheel was established to evaluate and analyze the porosity and pore size of the grinding wheel working face.The accuracy of the image recognition method in evaluating the porosity and pore size is verified by the measurement test of the porosity on the surface of the grinding wheel.An accurate and fast method is provided for the evaluation and analysis of the porosity characteristics of the grinding wheel surface.(3)The ultra-precision grinding test of single crystal silicon was carried out by using the fine-grained diamond grinding wheel of porous vitrified bond.Using the built test platform,single-crystal silicon grinding experiments were carried out on grinding wheels with different surface porosity characteristics.surface morphology.The test results show that with the increase of the porosity of the grinding wheel,the wear amount of the grinding wheel becomes larger,and the maximum wear amount reaches 2967.3 mm3;the average surface roughness Ra of the silicon wafer after grinding by the grinding wheel with porosity of 72.8%,76.4% and80.2% is 34.3 nm,22.4 nm and 19.9 nm.The evaluation method of porosity characteristics of fine-grained diamond grinding wheel studied in this paper is not only conducive to the study of the manufacturing process of the grinding wheel,but also to the research of the grinding performance of the grinding wheel.It has important guiding significance for realizing the localization of porous vitrified bond finegrained diamond grinding wheels.