DIAMOND-LIKE CARBON-FILMS DEPOSITED USING A BROAD, UNIFORM ION-BEAM FROM AN RF INDUCTIVELY-COUPLED CH4-PLASMA SOURCE

Diamond-like carbon (DLC) films with 12-25 GPa hardnesses and 3-400 nm thicknesses were deposited on silicon, Al2O3-TiC substrates, and perm alloy coated with Al2O3-TiC substrates using a broad, uniform ion beam from an RF, inductively coupled, CH4-plasma (ICP) source (30 cm). The deposition process represents a significant advance in the ability to : (1) accomplish the desired balance between mechanical, optical and e lectrical properties by utilizing different RF powers to vary the plas ma density and electron temperature; (2) improve step coverage when th e film is deposited on patterned or rough substrates; (3) carry out re liable fault-free and long duration operation. The RF inductively coup led ion beam source can be operated with highly reactive ion beam proc esses for long periods of time. In particular, the source demonstrates excellent compatibility with pure oxygen. The ability of an O-2-plasm a to etch hydrocarbon precipitates allowed us to utilize this procedur e as an effective ''on-line'' ion source clean-up. Highly reproducible deposition rates (< 5% from run to run for over several hundred hours ) have been achieved by utilizing a CH4-plasma conditioning procedure for the plasma-surface interaction stabilization. The deposition unifo rmity was within 5% over 9 in. Deposition kinetics as well as the mech anical and electrical properties have been investigated and discussed. (C) 1998 Elsevier Science S.A.