Effect of surface species concentrations and temperature on diamond film morphology in inductively coupled rf plasma CVD

Diamond films were deposited with an r.f. plasma operating at atmospheric pressure. The gas composition above the growth surface was measured with a gas chromatograph. Experiments were conducted over a range of methane flow rates and substrate temperatures. Films were characterized by SEM and X-ray diffraction texture analysis. Increases in either input methane-hydrogen ratio or substrate temperature caused film morphology to shift from {111} toward {100} faceting, while the measured ratio of CH4 to C2H2 decreased. We speculate that the temperature effect on species concentrations and film morphology is due to the temperature dependence of surface-catalyzed atomic hydrogen recombination. (C) 1997 Elsevier Science S.A.