A-C-H FILMS DEPOSITED IN THE PLASMA OF BARRIER AND SURFACE DISCHARGESAT ATMOSPHERIC-PRESSURE

The aim of this work is the synthesis of the diamond-like coatings in a barrier and surface discharges at the atmospheric pressure and the i nvestigation of their properties. The best characteristics had the coa tings obtained from methane (the ratio of hydrogen atoms to carbon ato ms is H/C=1.04, the ratio of the diamond-like and graphite-like C-C bo nds sp(3):sp(2)=100%:0%) and from the acetylene and hydrogen mixture ( 1:19) (H/C=0.73, sp(3):sp(2)=68%:32%) in barrier discharge, as well as from methane in surface discharge (H/C=0.69-1.03, sp(3):sp(2)=78%:22% ). By their chemical and phase composition these coatings are close to the diamond-like hydrogenated (a-C:H) films obtained by traditional m ethods of plasma assisted chemical vapor deposition at low pressure (< 10 Torr). At the same time proposed methods for fast deposition of a-C :H films make this process less expensive compared to the conventional techniques, which implies that the field of application of these film s can be widened substantially. (C) 1997 Elsevier Science S.A.