Hydrogen plasma and atomic oxygen treatments of diamond: Chemical versus morphological effects

Chemical bonding and morphology of chemical vapor deposited diamond films were studied using high resolution electron energy loss spectroscopy and atomic force microscopy, following hydrogen plasma and atomic oxygen exposures. The hydrogen plasma exposure resulted in preferential etching of nondiamond carbon phases, selective etching of diamond facets, and termination of the diamond surfaces by sp3-C–H species. Exposure to atomic oxygen, on the other hand, produced significant chemical changes resulting in oxidized hydrocarbon ill defined top layer, while the morphology of the surface remained almost unchanged.