Preparation And Performance Of Vitrified Bond Lapping Pellets Based On Solid-phase Fenton Reaction For Single-crystal SiC

With the rapid development of 5G communication and the semiconductor technology industry,higher requirements are put forward for the development and manufacture of semiconductor devices.As a typical third-generation semiconductor material,silicon carbide(Si C)due to its outstanding physical,mechanical and chemical properties is widely used in high-temperature,high-frequency and radiation-resistant devices.However,the high hardness and brittleness of Si C and its stable chemical properties make it extremely difficult to process.This paper based on the principle of solid-phase Fenton reaction proposes to prepare solid-phase Fenton reaction vitrified bond lapping pellets and use them in the lapping of single-crystal Si C wafers to improve processing efficiency and processing quality.The physical and mechanical properties of the lapping pellets under different preparation conditions(abrasive type,vitrified bond content,molding pressure,sintering temperature and pore-forming agent content)were studied,and the results show that:The type of abrasive affects the physical and mechanical properties of the lapping pellets;when the binder content is 26 wt.%,the hardness and flexural strength of the lapping pellets are the highest are 82.18HRB and 74.77 MPa,respectively;with the increase of the molding pressure,the hardness and flexural strength of lapping pellets increased and then decreased;with the increase of sintering temperature,the hardness and flexural strength of lapping pellets increased and then decreased;with the increase of porogenic agent content,the hardness and flexural strength of lapping pellets decreased and the porosity increased.The catalytic rate of the solid-phase Fenton reaction was investigated for different ratios of lapping pellets under different conditions of abrasive fractions.The results show that:under the influence of the components,the catalytic performance of the lapping pellets decreased with the increase of the particle size of the solid-phase catalyst Fe₃O₄ and increased with the increase of the mass fraction of the solid-phase catalyst Fe₃O₄;under the influence of the components of the lapping solution,in the first 30 min,the catalytic performance of the lapping pellets increased with the increase of the mass fraction of H₂O₂.During the whole stage,the lapping solution with a mass fraction of H₂O₂ of 10 wt.%completed the fading first.In the first 30 min,the catalytic performance of the lapping pellets diminished with the increase of p H,throughout the stage p H=3 the lapping solution was the first to complete the fading.The effects of the composition parameters(abrasive type,abrasive particle size,Fe₃O₄particle size,Fe₃O₄ mass fraction)and the process parameters(lapping pressure,lapping plate speed,H₂O₂ mass fraction,and p H of lapping solution)on single crystal Si C lapping processing effect were systematically studied.The results show that the material removal rate increases with the increase of abrasive particle size,and the surface quality becomes worse;the processing effect becomes worse with the increase of Fe₃O₄ particle size,and the material removal rate decreases with the increase of Fe₃O₄ mass fraction,and the surface roughness decreases and then increases.With the increase of lapping pressure and rotating speed of lapping plate,the material removal rate increases,and the surface roughness decreases and then increases.With the increase of H₂O₂ mass fraction.As the p H value increases,the material removal rate decreases,and the surface roughness decreases and then increases.The optimized process parameters were used to process single-crystal Si C with an original roughness of about Ra 100 nm for 60 min to obtain a single-crystal Si C with a low-damage surface with surface roughness all below 1.06 nm.The process of solid-phase Fenton reaction ceramic bond lapping pellets lapping process is the result of the combined action of chemical and mechanical action.The chemical action not only oxidizes the single crystal Si C surface to generate an oxide layer that can be removed more easily,accelerate the removal of materials,and reducing the lapping process,and improving the surface quality but also changes the structure of the lapping pellet surface and affects the wear of the lapping pellet.Therefore,controlling the balance of chemical and mechanical effects during the lapping process can not only achieve high speed and high-quality lapping of single-crystal Si C but also improve the service life of the lapping pellets.