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 A/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 discharges did not product significant etching of the diamond, but SF6/O2 mixtures had slightly faster rates than O2 alone.