The effect of radio frequency substrate biasing in the deposition of diamond-like carbon films in an electron cyclotron resonance discharge

Abstract

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.