Molecular Beam Epitaxial Growth of High-Quality GaN Nanocolumns

Published

January 1, 2006

Author(s)

J E. Van Nostrand, K L. Averett, R Cortez, J Boecki, C E. Stutz, Norman Sanford, Albert Davydov, J D. Albrecht

Abstract

Vertically oriented GaN nanocolumns (NCs) approximately 90+10 nm wide and 0.75 microns tall were grown byt plasma-assisted molecular beam epitaxy on Al_(2)O_(3)(0001) and Si(111). The dense packing of the NCs gives them the appearance of a continuous film in surface view, but cross-sectional analysis shows them to be isolated nanostructures. Low temperature photoluminescence measurements of NCs show excitonic emission with a dominant, narrow peak centered at 3.472 eV and FWHM of 1.26 meV. This peak is identified as the ground state of the A free exciton as confirmed by reflection measurements. Cross-sectional transmission electron microscopy identifies the NC microstructure as wurtzite GaN and that the NCs are largely free of defects. The GaN NCs are subsequently utilized as a defect free vehicle for optical studies of Si doped GaN; and the donor state was identified through low-temperature photoluminescence experiments.

Citation

Journal of Crystal Growth

Volume

287

Pub Type

Journals

Keywords

GaN nanocolumns, GAN photoluminescence, transmission electron microscopy

Citation

Van Nostrand, J. , Averett, K. , Cortez, R. , Boecki, J. , Stutz, C. , Sanford, N. , Davydov, A. and Albrecht, J. (2006), Molecular Beam Epitaxial Growth of High-Quality GaN Nanocolumns, Journal of Crystal Growth (Accessed December 3, 2024)