Deposition of hydrogenated carbon film in a magnetically confined CH4 rf discharge

Hydrogenated carbon film deposition was carried out in a CH4 rf (13.56 MHz) plasma generated by a conventional magnetron sputtering system with parallel electrode configuration. Both diamond-like carbon (DLC) and transparent soft (TS) films were obtained. The film deposition rates of both films were decreased with increasing substrate temperature, suggesting that the incorporation of the precursor molecule into the growing film was predominantly mediated by a physisorbed layer. Activation energies of about 1.0 and 0.12 eV were obtained for the TS films, which were considered to be associated with the desorption energy of a physisorbed precursor molecule and the etching of adsorbed molecule by H atom, respectively. A weak temperature dependence of the DLC film deposition rate suggested that the direct incorporation of ionic species together with the simultaneous ion-induced etching contributes considerably to the film deposition process. The deposition rates of both films depending on residence time of source gas molecule were also measured, which also supported these deposition models. (C) 2000 Elsevier Science Ltd. All rights reserved.