Correlations between structural, electrical and optical properties of GaN layers grown by molecular beam epitaxy

Screw and edge dislocation densities were estimated from X-ray diffraction profiles of GaN layers grown by molecular beam epitaxy. The results were co nfirmed by transmission electron microscopy. The layers had varying thickne sses or were deposited on differently nitridated sapphire substrates. It wa s found that the low temperature Hall mobility correlates with the screw di slocation density whereas the full width at half maximum of the donor bound exciton emission line changes similarly as the edge dislocation density.