SELECTIVE-AREA GROWTH OF GAN ALN HETEROSTRUCTURES/

Selective area growth of GaN stripes with a flat and smooth (0 0 0 1) top plane has been achieved by optimizing MOCVD growth conditions. Str ain of AlN/GaN heterostructure is reduced on selectively grown stripes even for a total AIN layer thickness of 200 nm. Although AlN growth i s observed on SiO2 masked areas, the selectivity of subsequent GaN lay ers is conserved. In comparison, cracks or macro-step formation appear for growth on wide stripes. Etch pit density of selectively grown GaN /AlN multi-layer structures seems to be greatly reduced to 1/1000 comp ared to the wide stripe growth. (C) 1998 Elsevier Science B.V. All rig hts reserved.