Phonon deformation potentials of wurtzite AlN

A strained AlN buffer layer used for the growth of a nitride-based superlattice on silicon carbide was studied by combining x-ray diffraction measurements and Raman spectroscopy. The deformation potentials have been derived from strains and frequency shifts for most long-wavelength optical phonons. The obtained values are compared with recent theoretical calculations and experimental determinations, restricted for the latter to a few accessible modes on account of constraints imposed by the methods of investigation. (C) 2003 American Institute of Physics.