Structural characteristics of diamond films prepared by thermal chemical vapor deposition processes

Abstract

Abstract Diamonds were synthesized by thermal chemical vapor deposition on molybdenum and silicon substrates. Using CH 4 H 2 as the precursor gas mixture, distinct growth steps on (111) faces were observed for diamonds prepared at 950°C on molybdenum substrates. No growth spirals were found on the (111) planes, indicating an apparent layerwise growth induced by a two-dimensional nucleation process rather than a screw dislocation mechanism. As the temperature of the molybdenum substrate was increased to 1060°C, the (100) planes of diamond were dominant in the film's surface morphology with no distinct growth steps observed. The termination of the outermost surface of the diamond films by CH 2 groups was suggested by Fourier transform IR analysis.