The characteristics of confined epitaxial growth were investigated with the aim of determining the contributing effects of mask characteristics (spacing, feature size) and growth conditions (V/III ratio, pressure, temperature) upon the efficiency of the approach to dislocation density reduction in GaN. In addition to standard (secondary electron and atomic force) microscopy, electron channelling contrast imaging was used to identify extended defects over large (tens of microns) areas. Using this method, it was shown that by confining epitaxial growth, high-quality GaN could be grown with dislocation densities approaching zero.

Approach for Dislocation Free GaN Epitaxy. J.K.Hite, M.A.Mastro, C.R.Eddy: Journal of Crystal Growth, 2010, 312[21], 3143-6