Dinh, D. V.; Conroy, M.; Zubialevich, V. Z.; Petkov, N.; Holmes, J. D.; Parbrook, P. J.

2015

January

Journal of Crystal Growth

Single phase (112¯2) AlN grown on (101¯0) sapphire by metalorganic vapour phase epitaxy

Published

()

414

94

99

Heteroepitaxial growth of AlN buffer layers directly on(101-0) sapphire substrates by metalorganic vapour phase epitaxy has been investigated. A single-step growth procedure without a sapphire nitridation was employed resulting in mirror-like crack free 1:1–1:6 μm thick AlN layers of single phase (112-2) orientation. Trimethylaluminum pre-dose time and reactor pressure were optimized for surface roughness and crystal quality. The crystal quality was found to degrade with increasing pre-dose time and also reactor pressure. The smallest full width at half maximum value for on-axis X-ray rocking curve of the (112-2) AlN layers was about 610 arc sec and 1480 arc sec along [-1-123] AlN and [1-100] AlN, respectively. The surface roughness, measured by atomic force microscopy using a 10 x 10 μm2 area, aas in the range 2.6–3.5 nm. A basal stacking fault density of 7 x 105 cm-1 was estimated by transmission electron microscopy.

Amsterdam, The Netherlands

http://www.sciencedirect.com/science/journal/00220248

10.1016/j.jcrysgro.2014.09.043

Science Foundation Ireland