Improvement of Process Reproducibility and Particle Reduction for YF₃Coating by Collision Assisted Sintering Process in Reactive Ion Etching

In reactive ion etching process, generation of particles and deterioration in process reproducibility due to high aspect ratio processing have become problems. In this study, YF3 coating was investigated using collision assisted sintering process (CASP) technique to reduce particles and improve process reproducibility. It was clarified that the CASP had possibility of a high-density coating with fewer cracks and voids than atmospheric plasma spraying (APS) coating. The amount of etching and surface roughness reduced to 92% and 31%, respectively, as compared to APS coating. The surface polishing for the APS-YF3 coating also reduced the amount of etching by 4%, and the CASP-YF3/APS-Y2O3 structural coating reduces desorption rate of particles by 25%. These results suggested that the possibility of suppressing particle generation and improving process reproducibility due to a high-density coating.