ECR plasma etching of chemically vapour deposited diamond thin films

Arc jet deposited films of diamond have been patterned using Au or photoresist masks and electron cyclotron resonance (ECR) O₂ discharges. To achieve anisotropic features, additional RF-induced DC biasing of the sample is necessary. Diamond etch rates of 2000 AA/min were obtained for 1 mtorr, 400 W O₂ discharges with -80 V DC bias. The etch rates increase with either pressure or microwave power as a result of a greater density of atomic oxygen in the plasma. Chlorine (BCl₃)-based did not product significant etching of the diamond, but SF₆/O₂ mixtures had slightly faster rates than O₂ alone.