EFFECT OF ATOMIC-HYDROGEN ON THE SURFACE-TOPOGRAPHY OF CHEMICALLY VAPOR-DEPOSITED DIAMOND FILMS - AN ATOMIC-FORCE MICROSCOPY STUDY

Atomic hydrogen is one of the key constituents in the growth of CVD diamond. In this work the effect of atomic hydrogen on the surface topography of CVD diamond films has been investigated. Diamond films were deposited on silicon substrates by the hot filament technique. In a subsequent process the diamond films were treated with atomic hydrogen. In addition to etching, small bumps were observed on the diamond facets. The size of the bumps were of the order of 50 nm in diameter and 5 nm in height. They contained the diamond phase, even though they were round shaped. For shorter times of exposure to atomic hydrogen, the diamond facets were almost atomically flat, except for the bumps. However, for longer times of exposure to atomic hydrogen the overall surface roughness, which started at the edges of the facets, increased.