ETCHING OF POLYCRYSTALLINE DIAMOND FILMS BY ELECTRON-BEAM ASSISTED PLASMA

Polycrystalline diamond films were processed in a direct current plasm a produced by a self-focused electron beam using combinations of H-2, O-2, and He as the processing gas. The film surfaces were observed by scanning electron microscopy, and characterized by x-ray photoelectron spectroscopy. It was found that for the case in which O-2 was include d in the processing gas, a high density of etch pits appeared on (100) faces of diamond grains, and oxygen was either physisorbed or chemiso rbed at the film surface. It was demonstrated that the etching apparat us used was capable of forming at least a 5-mu m wide pattern of polyc rystalline diamond film.