PLASMA DEPOSITION AND ETCHING OF DIAMOND-LIKE CARBON-FILMS

Diamond-like carbon films have been deposited from ternary mixtures of butadiene, hydrogen and argon in a parallel plate plasma reactor at constant pressure and power. These films have been etched in O2 and CF4/O2 plasma discharges. A new linear relationship between the composition of the deposition gas mixture and a dimensionless number (E(N)) defined in terms of etch and deposition rates and the bias voltage during deposition has been derived. E(N) is a function of the ion flux during deposition. Electron-impact ionization processes are considered for relating the ion flux to the feed gas composition and ionization potentials. The etch and deposition rate data follow this linear relationship very well. The proportionality constant in this linear relationship varies with composition for CF4/O2 etching data. Film hardness and failure modes on silicon and glass substrates are also described.