To inspect the treatment effect of high power plasma on fused silica, inductively coupled plasma with power of 36kW at atmospheric pressure , CF4 as working gas, was applied to carry out the etching experiments of fused silica, in which the effect of CF4 flow rate on material remove rate, surface roughness and surface profile were investigated. The experimental results showed that the material remove mechanism of fused silica treated by high power inductively coupled plasma was a result of the comprehensive effect of melting and evaporation at high temperature, chemical etching and bombardment of high energy ions. The fused silica remove rate reached 0.208g/min with the CF4 flow rate of 2.8L/min. The surfaces of fused silica samples became rougher with the increased CF4 flow rate, as the subsurface micro-cracks were opened and formed etching pits by the plasma etching. The surface global profile was affected seriously by the distance between outer plasma flame and samples while the local profile was dominated by etching pits.
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