Negative pulsed voltage discharge and DLC preparation in PBIID system

The spectrum of optical emission from the plasma of hydrocarbon gases was measured with a photomultiplier and an optical multichannel analyzer in PBIID (plasma-based ion implantation and deposition) system. When negative pulsed voltage was applied to a sample, a strong optical emission was observed. It is important to know a contribution of negative pulsed voltage discharge on DLC (diamond-like carbon) synthesis. Spectra of CH (431 nm), Hα (656 nm), Hβ (486 nm) and Hγ (434 nm) were observed. Deposition rate of DLC film using acetylene gas was almost proportional to intensity of CH spectrum.