Electron Cyclotron Resonance Etching Of Sic In Sf6/O-2 And Nf3/O-2 Plasmas

Etching of β-SiC with electron cyclotron resonance (ECR) system was investigated. Anisotropic and smooth etching of SiC was demonstrated with SF6/O2 based discharges. The root-mean-square roughness increases from 35 nm to 56 nm for as deposit and etched sample, respectively. The addition of small amount oxygen enhanced the etch rate of SiC slightly, but further increase of oxygen content reduced the etch rate which resulted from dilution of F ion and free radical densities. NF3/O2 based discharges also showed same trends and produced anisotropicly etching. However, the smoothness is not as good as SF6/O2 based discharges.