Investigation of the relationship between plasma etching characteristics and microstructures of alumina ceramics for chamber parts

Corrosion of ceramic chamber parts in mass-production plasma etching equipment causes the decrease in the production yield of LSI and overall equipment effectiveness. For the development of chamber parts with high resistance and long useful life under plasma etching environment, the investigation of detailed corrosion mechanism is required. In this study, we investigate the relationship between plasma etching characteristics and microstructures of alumina ceramics, which is the most typical ceramic material for chamber parts, under mass-production plasma etching condition using CF4 gas. The results of this study indicate that the microstructures have little influence on the etching amount, whereas the surface roughness depends on the microstructures such as grain size and microstructural defect.