Dg. Chtchekine et al., PROPERTIES OF LOW-PRESSURE CHEMICAL-VAPOR EPITAXIAL GAN FILMS GROWN USING HYDRAZOIC ACID (HN3), Journal of applied physics, 81(5), 1997, pp. 2197-2207
We have grown high-quality GaN films on sapphire using a new nitrogen
precursor, hydrazoic acid (HN3). Films were grown at 600 degrees C on
(0001) sapphire substrates in a low-pressure chemical-vapor-deposition
system using triethylgallium and hydrazoic acid as precursors. Subseq
uently, we have conducted a complete study of the surface, structural,
electrical, and optical properties of these GaN films, and our early
results are very encouraging. All films were of wurtzite crystal struc
ture, slightly polycrystalline, and n type at about 2x10(17) cm(-3). W
e find the films to be efficient light emitters in the near-band edge
region of the spectrum. Analysis of the emission energies and kinetics
suggests that the midgap emission results from a superimposed deep-do
nor-to-shallow-acceptor emission and a deep-donor-to-valence-band emis
sion, where the deep donor consists of a distribution of energy levels
, thereby yielding a broad emission band. (C) 1997 American Institute
of Physics.