Temperature-dependent growth and characterization of N-polar InN films by molecular beam epitaxy

Abstract

N-polar InN films were grown as a function of temperature (∼440–620 °C) on 500 nm thick GaN template by plasma-assisted molecular beam epitaxy. InN films grown at different temperatures showed different morphologies that could be roughly divided into two regions. Dendritic morphologies could be observed at temperatures lower than 540 °C while step-flow-like morphology could be obtained at temperatures higher than 540 °C. Crystalline quality became better with the increase of growth temperature at temperatures lower than 540 °C and almost saturated at higher temperatures. Strong photoluminescence was observed at room temperature and 13 K with the emission peaks at 0.67 and 0.7 eV, respectively. Based on our results, the growth temperature above 540 °C was recommended for N-polar InN epitaxy. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)