Nitrogenated diamond produced by introducing ammonia into the gas feed in hot-filament CVD

Nitrogenated diamond and carbon nitride films have been produced using ammnonia as the source of atomic nitrogen. A feed mixture of C2H5OH + NH3 + H-2 was used in a hot filament CVD reactor. The deposition parameters were optimized for the growth of well-faceted crystals onto either SiO2 or undoped diamond substrates. Film structure and morphology were studied using optical and atomic force microscopies, and Raman and photoluminescence spectroscopies. Three types of film, according to the deposition substrate used and the nitrogen doping, have been identified. All films presented semiconductor characteristics and their deep and shallow activation energies have been determined from resistance versus temperature measurements. (C) 1999 Elsevier Science S.A. All rights reserved.