Properties of metal/diamond interfaces and effects of oxygen adsorbed onto diamond surface

Abstract

The current-voltage characteristics of Schottky diodes fabricated using as-grown diamond films depend on the electronegativities of metals. However for diamond films oxidized by boiling in a saturated solution of CrO in H2SO4 or by exposure to an oxygen plasma, this dependence vanishes. This is because of the adsorption of oxygen onto the surfaces of diamond synthesized by chemical vapor deposition. It has been shown by x-ray photoelectron spectroscopy that very little oxide is present on the as-grown surfaces, but that at least submonolayer oxygen coverage is present on the oxidized surfaces.