Removal function and chemical composition of RS-SiC surface processing by atmospheric pressure plasma processing

Reaction-sintered silicon carbide (RS-SiC) has been widely applied in space telescope mirrors, reflector, microelectronic mechanical systems due to its excellent properties. These applications require high surface accuracy and quality, but traditional mechanical contact polishing methods are hard to process this material due to the hardness and poor machinability. In this paper, atmospheric pressure plasma processing (APPP) which is a non-contact optical manufacturing technique with highly efficient and subsurface damage-free has been proposed to process this material, and optimal process parameter mainly about influence on removal function for machining processing RS-SiC have been found. The sample was observed and analyzed by scanning white-light interferometer (SWLI), which showed the calculated Peak- Maximum removal rate (MRR) and Volume-MRR were 12.526μm/min and 0.1298mm3 /min. Meanwhile, the surface chemical composition of RS-SiC was also investigated by XPS to reveal the plasma etching processes. The results illustrated that small number of radicals CxFy were introduced onto the RS-SiC surface during the plasma process which could be generated during the process of the reaction gas CF4 being excited. The process parameters and analysis of surface chemical composition in this paper will guide the further processing of RS-SiC.