Phase identification of boron nitride thin films by polarized infrared reflection spectroscopy

Six different types of boron nitride films were investigated by polarized infrared reflection spectroscopy. Films with a highly cubic, mixed cubic and noncubic, and exclusively noncubic phase composition were synthesized using ion beam assisted deposition. Additionally, postdeposition argon ion irradiated cubic and noncubic boron nitride films as well as a nitrogen implanted boron sample were analyzed. Using this technique, besides the cubic phase, two different noncubic modifications, layered anisotropic and amorphous, could be distinguished. A preferential orientation of the normal axis of the sp(2)-bonded basal planes parallel to the substrate surface was observed. (C) 1996 American Institute of Physics.