Micro-Arc Plasma Processing Technology And Experimental Study Of Single Crystal Silicon

Monocrystalline silicon is widely used in the photovoltaic industry,aerospace,integrated circuits and microelectronics,etc.because of its characteristics of radiation resistance,high temperature resistance,easy purification and miscellaneous.However,the high hardness and high brittleness of single crystal silicon make it often occur that the cutting efficiency is low,the surface quality is poor,and even cracks and smashing occur when cutting.Even when it is processed by the non-contact WEDM method,the surface quality of the single crystal silicon after cutting is poor because of the large discharge energy.The micro-arc plasma cutting is based on the wire-cutting technology,and the discharge area is controlled as much as possible in the spark discharge stage to avoid the occurrence of arc discharge,thereby avoiding the discharge energy being too high and causing the surface of the workpiece to be burned.In this paper,the cutting mechanism of micro-arc plasma cutting single crystal silicon is explored through the combination of theory,simulation and experiment.The specific work is as follows:(1)The micro-arc plasma discharge region is described based on the liquid-phase pulse discharge theory;the theoretical derivation of the micro-arc plasma discharge pre-breakdown process and the formation process of the discharge channel based on the field ionization and thermal bubble pre-breakdown mechanism In combination with the theory of electromagnetic induction,the electromagnetic field around the wire is cut by micro-arc plasma cutting semiconductor material,and the electromagnetic field around the wire is simulated by finite element software.(2)Based on the theory of thermodynamics,combined with micro-arc plasma cutting of single crystal Si,the numerical simulation of micro-arc plasma single-pulse discharge cutting single crystal Si was carried out by ICEM software and Fluent software to analyze the single crystal Si discharge micro-domain.Temperature field distribution and melting and solidification process of a single etch pit.The effects of single-pulse discharge on single crystal Si were investigated under different electrical parameters.(3)Based on the shape of single-pulse discharge electro-etching pit,the micro-arc plasma continuous pulse discharge cutting single crystal Si was modeled and simulated by Matlab software,and the single-mode Si was cut by micro-arc plasma through the established model.The surface root mean square roughness is predicted,and the prediction results under different parameters are finally verified by experiments.(4)The mechanism of micro-arc plasma cutting single crystal silicon with wire saw as electrode was studied.The single crystal silicon is processed by wire saw cutting,micro-arc plasma cutting with molybdenum wire as electrode and micro-arc plasma cutting with wire saw as electrode,the advantages and disadvantages of micro-arc plasma cutting with wire saw as electrodes are analyzed and compared.