Title: Growth and characterization of a-plane Al(x)Ga(1-x)N alloys by metalorganic chemical vapor deposition
Authors: Huang, H. M.
Ling, S. C.
Chen, J. R.
Ko, T. S.
Li, J. C.
Lu, T. C.
Kuo, H. C.
Wang, S. C.
Department of Photonics
Issue Date: 1-Mar-2010
Abstract: The non-polar a-plane Al(x)Ga(1-x)N alloys on GaN epitaxial layer with different Al compositions (0 <= x <= 0.2) were grown on r-plane (1 (1) over bar 0 2) sapphire substrates by using low-pressure metalorganic chemical vapor deposition (MOCVD) and the Al composition x were estimated from the X-ray diffraction measurements. According to the result of asymmetric X-ray reciprocal space mapping, AlGaN layer was coherently strained to the underlying GaN template. The a-plane AlGaN alloy with relatively lower Al composition showed a flat surface with reduction of pits. The best mean roughness of the surface morphology was 1.18 nm. The photoluminescence (PL) result revealed that the PL peak position shifted from 3.42 to 3.87 eV with 0 <= x <= 0.2. Apart from the shifted peak position with increasing Al content, the PL emission intensity and surface morphology of the a-plane AlGaN alloy with relatively low Al content show slightly better characteristics than that of the a-plane GaN and AlGaN with higher Al composition. (C) 2010 Elsevier B.V. All rights reserved.
URI: http://dx.doi.org/10.1016/j.jcrysgro.2009.12.064
ISSN: 0022-0248
DOI: 10.1016/j.jcrysgro.2009.12.064
Volume: 312
Issue: 6
Begin Page: 869
End Page: 873
Appears in Collections:Articles