m-plane (101̱0) InN heteroepitaxied on (100)-γ-LiAlO2 substrate: Growth orientation control and characterization of structural and optical anisotropy
Journal
Journal of Applied Physics
Journal Volume
107
Journal Issue
7
Pages
073502-1 - 073502-7
Date Issued
2010
Author(s)
Hsiao, C.-L.
Chen, J.-T.
Hsu, H.-C.
Liao, Y.-C.
Tseng, P.-H.
Chen, Y.-T.
Feng, Z.C.
Tu, L.-W.
Chou, M.M.C.
Abstract
Heteroepitaxial growth of m -plane (10 1- 0) InN film on (100) -γ -LiAlO2 (LAO) substrate has been realized by plasma-assisted molecular-beam epitaxy. Surface treatment of LAO substrate plays an important role in controlling the resultant phase and purity of m -plane InN. X-ray diffraction, reflection high-energy electron diffraction, electron back scatter diffraction, and transmission electron microscopy (TEM) studies revealed formation of pure m -plane InN film using substrate preannealed at 800 °C but without any nitridation. In contrast, using substrate with nitridation but otherwise identical pretreatment and growth conditions, c -plane (0001) InN columnar structure was grown, instead of m -plane InN film. Structural anisotropy of the m -plane InN epitaxied on LAO is attributed to the I 1 type base-plane stacking faults according to the modified Williamson-Hall and TEM analyses. A rectangular-to-rectangular atomic stacking sequence and a commensurately lattice-matched condition in epitaxial direction of [1 2- 10] InN [001] LAO with a small misfit strain of ∼0.2% are proposed to realize this heteroepitaxy. Angle-dependent polarized UV-Raman spectra showed that all the InN phonon modes follow Raman selection rule well. Strong polarization anisotropy of photoluminescence (PL) emission located at ∼0.63 eV was observed, as evidenced by a high polarization degree of 87% of the m -plane InN determined by infrared polarized PL spectroscopy. © 2010 American Institute of Physics.
SDGs
Publisher
American Institute of Physics
Type
journal article