Design And Experimental Study On Magnesium Oxychloride Bonded Diamond Pad With Phyllotaxis Grooves

As the basics of the development of the electronics industry,semiconductor applications include consumer electronics,communications,transportation,vehicle,medical testing equipment,robotics,photovoltaic power generation and other scenarios.As a kind of precision ultra-precision machining method,fixed abrasive lapping and polishing technology is widely used in semiconductor thinning and polishing process.As an important consumable of grinding and polishing technology,fixed abrasive lapping tool is constantly required to have better machining performance due to technological progress.Therefore,it is of great theoretical significance and practical value to study the design and preparation of fixed abrasive lapping tools for the realization of high quality and efficient processing of semiconductor materials.In recent years,magnesium oxychloride bonded abrasive tools have attracted extensive attention because of their excellent physical and chemical properties,simple preparation,green pollution-free,which other binders do not have.However,the existing magnesium oxychloride bonded abrasive tools have poor comprehensive performance and simple structure,so it is difficult to be used in grinding hard and brittle materials.Therefore,this paper starts from the magnesium oxychloride bonded abrasive lapping tools formula optimization,carried out the selection of tools raw materials selection and different formulations tools performance testing,determined the final optimization formula.The structural design method of the lapping plate structure with phyllotaxis grooves was proposed,and the structure of the groove was optimized by flow field numerical simulation technology.Magnesium oxychloride fixed diamond plate with phyllotaxis grooves and one with non-groove were prepared by using the optimized formula,and applied to sapphire lapping process.The processing performance of the plates were analyzed and discussed.The main contents and conclusions of this paper are as follows:(1)Optimize and improve the formulation of magnesium oxychloride bonded abrasive tools to improve the comprehensive performance of magnesium oxychloride bonded abrasive tools.The influence of different binder base ratio,abrasive concentration and modifier on abrasive strength,hardness,water resistance and porosity was systematically analyzed,and the optimized formula with better comprehensive performance was obtained.Specifically,light calcined magnesia34.84 wt%,magnesium chloride solution 39.9 wt%,abrasive 24.91 wt%,phosphoric acid 0.35 wt%,hollow glass microsphere 0.8 wt%.(2)Based on the principle of bionics,the design of phyllotaxis grooved plate is proposed.By systematically analyzing the flow field performance of the phyllotaxis grooved plate and optimizing the design parameters of the phyllotaxis grooves,the phyllotaxis grooved plate structure with good average flow velocity and nonuniformity of flow velocity was obtained.The structure parameters of the phyllotaxis grooves: the phyllotaxis combination is 55×21,the phyllotaxis distribution density is 10 and the groove width is 1.5 mm.(3)Based on the formulation and structure parameters of the lapping plate,magnesium oxychloride fixed diamond plate with phyllotaxis groove and one with non-groove were prepared by casting and curing process,respectively,and repaired to complete the preparation of the lapping plate.(4)The machining effect of lapping sapphire with phyllotaxis grooved plate and non-grooved plate was systematically studied.The results show that both the phyllotaxis grooved plate and non-grooved plate have better machining performance.Compared with non-grooved plate,the surface quality of lapping sapphire with phyllotaxis grooved plate is better,but the material removal rate is slightly lower.The surface Ra and PV of lapping sapphire phyllotaxis grooved plate are 46.51 nm and 1.336 μm,respectively,and the material removal rate is 0.373 μm/min.(5)Comparing the surface characteristics of the plate after lapping with the phyllotaxis grooved plate and non-grooved plate,it is found that under the same processing conditions,the blockage condition of the phyllotaxis grooved plate is obviously better than that of the non-grooved plate,indicating that the lapping plate with the phyllotaxis grooves can carry out the grinding chip transportation better and reduce the grinding chip adhesion and blockage on the surface of the lapping plate.