Effect of dilution gases in methane on the deposition of diamond-like carbon in a microwave discharge

Abstract

Diamond-like carbon was prepared by the decomposition of CH 4 in a microwave discharge. The effect of dilution gases, such as hydrogen, argon and helium, on the deposition was examined on the basis of identification of the deposits and the results of plasma diagnostics. When hydrogen was added diamond-like particles containing large amounts of hydrogen were obtained. Diamond-like films containing graphite and a smaller amount of hydrogen were deposited from the CH 4-Ar plasma. The deposits from CH 4 and CH 4-He plasmas consisted only of graphite. The correlation between the deposit and the species present in the plasma is discussed.