Deposition of films of cubic boron nitride and nitrides of other group III elements

摘要

Process for producing cubic boron nitride films on a substrate by activated dissociation reduction-reaction. Boric acid in the condensed state is evaporated in a vacuum chamber from a resistance-heated evaporation source and ammonia gas is introduced into the chamber. The vapor of the boric acid and the molecules of the ammonia gas are ionized by a beam of low-energy electrons in the reaction zone between the resistance-heated evaporation source and the substrate. The ammonia gas reacts with the boric acid in a two-step process in which (1) the boric acid is reduced by the atomic hydrogen formed by the dissociation of ammonia, and (2) the resulting boron atoms react with the nitrogen atoms released by the dissociation of ammonia to form boron nitride which deposits as a film onthe substrate. This film has the cubic boron nitride structure and is ready for use without requiring post-deposition heat treatment.