Epitaxial growth and characterization of InN nanorods and compact layers on silicon substrates

Abstract

AbstractThis work reports on the morphology and optical properties of wurtzite InN layers grown by plasma assisted molecular beam epitaxy (PA‐MBE) on Si(111) substrates. The layer morphology can be controlled by the effective indium to nitrogen molecular flux ratio, from N‐rich conditions that lead to InN nanorods, to stoichiometric conditions leading to compact InN layers. The nanorods deliver a much higher intensity of the photoluminescence emission than compact layers, with a full width at half maximum down to 34 meV, indicative of a high crystal quality. Raman and X‐ray measurements on the InN nanorods and compact layers confirm the practical full relaxation of both types of materials. TEM measurements reveal a perfect epitaxial alignment of Si substrate‐AlN buffer and InN epilayer with clean AlN‐InN interfaces when growth conditions are optimized. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)