New ‘‘diamondlike carbon’’ film deposition process using plasma assisted chemical vapor transport

We have deposited ‘‘diamondlike carbon’’ films on various substrates using a new plasma assisted chemical vapor transport process in a high rf power density presssure ratio gas discharge. The films reported here exhibit the following properties: (1) high transparency for wavelengths greater than 300 nm; (2) an index of refraction of ∼2 at 850 nm; (3) a hardness between that of quartz and sapphire, increasing with ion energy bombarding the deposition surface; (4) strong adhesion to KBr, sapphire, and Si substrates; (5) high dielectric strength; (6) inertness to highly reactive chemicals.