THE EFFECT OF RADIO-FREQUENCY SUBSTRATE BIASING IN THE DEPOSITION OF DIAMOND-LIKE CARBON-FILMS IN AN ELECTRON-CYCLOTRON RESONANCE DISCHARGE

The density, optical band gap, and hydrogen content of diamond-like carbon films have been controllably varied by radio frequency (rf) substrate biasing in an electron cyclotron resonance (ECR) discharge of CH4 and CH4-H2. The density varied from 1.4 to 2.2 g/cm3, the optical band gap from 2.7 to 1.2 eV, and the atomic fraction of hydrogen from 50% to 5% as rf substrate bias increased. Optical emission spectroscopy was used to characterize the glow discharge and establish the conditions under which either deposition or etching could occur.