Ma. Jacobson et al., SOME NEW FUNDAMENTAL PROPERTIES OF GAN SINGLE-CRYSTAL FILMS ON SIC AND SAPPHIRE SUBSTRATES, Nuovo cimento della Societa italiana di fisica. D, Condensed matter,atomic, molecular and chemical physics, biophysics, 17(11-12), 1995, pp. 1509-1512
The reflectance spectra of GaN/6H-SiC films and the absorption spectra
of GaN/Al2O3 films were studied and several fundumental parameters of
GaN-energy positions of exciton resonances omega(0), damping constant
s Gamma, longitudinal-transverse splittings omega(LT) and the oscillat
or strengths f of the exciton states were determined. A blue shift and
broadening of the luminescence band were observed in the luminescence
spectra of GaN quantum dots. The mean dot radius in the sample was es
timated to be about 4.5 nm.