Step-flow growth of InN on N-polarity GaN template by molecular beam epitaxy with a growth rate of 1.3 μm/h

Abstract

The effects of substrate temperature and surface stoichiometry on the growth behavior of InN were investigated in molecular beam epitaxy with in situ monitoring by reflection high-energy electron diffraction and spectroscopic ellipsometry. InN was grown on nitrided sapphire substrate or N-polarity GaN template. For both cases, InN layers were found in N polarity by coaxial impact collision ion scattering spectroscopy. At growth temperatures ranging from 470 to 590 °C, the N-rich condition was favorable for stable InN growth. Under the In-limited growth condition, the stepflow growth of InN was achieved on N-polarity GaN template at 580 °C with a growth rate of 1.3 μm/h. The FWHMs of X-ray rocking curves around InN (002) and (102) reflections were about 200-250 arcsec and 950-1100 arcsec, respectively. The InN layer grown with N polarity on GaN showed a Hall mobility as high as 800 cm2/V s with a background electron concentration of 2.1 × 1019 cm-3 at room temperature. © 2002 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.