Structural properties of InN thin films grown with variable growth conditions on GaN/Al2O3 by plasma-assisted MBE

Abstract

The structural characteristics of compact and columnar InN films grown by molecular beam epitaxy on GaN templates are investigated by transmission electron microscopy. Compact mode of growth is favoured at low substrate temperatures, below 500 °C, and by the introduction of an InN nucleation layer prior to the InN epilayer growth. Improved quality compact InN films, having threading dislocations with densities on the order of 109–1010 cm−2, are achieved by using high In/N flux ratios. Compact films generally exhibit higher in-plane lattice constant values than columnar ones and, consequently, higher densities of InN/GaN interfacial misfit dislocations.KeywordsMisfit DislocationFlux RatioCompact FilmElectron Beam DirectionXTEM ImageThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.