Application of Atmospheric Pressure Plasma in the Ultrasmooth Polishing of SiC Optics

摘要

This paper presents a novel, rapid and damage-free method to polish the ultra-smooth surface of the SiC optics. First, the basic philosophy of this method is introduced, which uses the active radicals got from CF_4 in the atmospheric pressure plasma zone to react with the SiC material at the optics surface to generate the vaporization of SiF_4. Then, the design of the atmospheric pressure plasma jet and the corresponding prototyping polishing facility are introduced. The theoretical analysis on the necessary conditions to generate the excited radicals is also presented in this part. To verify the effectiveness of this novel polishing method, experiments on the generation of atmospheric pressure plasma and the SiC optics polishing are carried out with our prototyping facility. The experiment results show that plasma discharge is stable at the atmospheric pressure and sub-nanometer roughness of the polished SiC surface can be obtained.