マイクロ波プラズマCVDによるダイヤモンド合成における遷移金属の影響

抄録

Diamond particles and films can be synthesized from vapor phase using low pressure CVD, but to obtain films, the surface of the substrate must first be scratched using diamond powder. Nucleation density depends on this pretreatment and it is difficult to keep the nucleation density and the film thickness uniform.
In this study diamonds were synthesized on various transition metal substrates from methane-hydrogen reaction gas system using microwave plasma CVD. Deposits were characterized by XRD and Raman spectroscopy, and substrate surfaces were measured by XPS. It was found that films were formed on both scratched and unscratched substrates of Ru, Rh, Ir and Pt in the platinum-group metal. This deposition of films is attributed to such properties of the platinum-group metals as their catalytic effect with respect to hydrocarbons, and chemisorption of radicals, atoms, ions, and molecules.