Effects at reactive ion etching of CVD diamond

Polycrystalline diamond chemical vapor deposition (CVD) films have been etc hed in both microwave and hot filament direct current plasmas. Hydrogen, hy drogen/argon and hydrogen/oxygen mixtures were used as reactive gases. Our results showed that bias-induced electron bombardment in hydrogen plasma di d not enhance the etching yield. In contrast, bias-induced ion bombardment in hydrogen promoted the increase of etching yield through the graphitizati on of diamond surface. Introduction of argon to the reactant precursors inc reased the ion bombardment, which in turn, led to higher defect density and the formation of non-diamond phase. The oxygen addition into hydrogen gas reverted the etching mechanism. in addition, oxygen acted as a medium for m aterial transport in the case of hot filament plasma. (C) 2000 Elsevier Sci ence S.A. All rights reserved.