Growth of AlGaN and GaN films on (11 20) Al2O3 substrates and the influence of V/III ratio on the properties of GaN films

• Published in: Journal of crystal growth Vol. 286; no. 1; pp. 28 - 31
• Main Authors: LIAO, Wei-Tsai, GONG, Jyh-Rong, LIN, Shih-Wei, WANG, Cheng-Liang, LIN, Tai-Yuan, CHEN, Keh-Chang, CHENG, Yi-Cheng, LIN, Wen-Jen
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 2006
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Iii-v semiconductors; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; Buffer layer; Inorganic compounds; 81.05.Ea A1. Characterization; Gallium nitrides; B1. Nitrides; Photoluminescence; Composition effect; 81.15.Tv; XRD; High temperature; Experimental study; Thin films; 78.55.Cr; Optical microscopy; Morphology; B2. Semiconducting gallium compounds; Aluminium nitrides; III-V semiconductors
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2005.10.001

AlGaN and GaN films were grown on (1120) Al2O3 substrates at elevated temperatures by alternate supply of trimethylgallium (TMG) with (or without) trimethylaluminum (TMA) in group III flow and NH3 in group V stream. The optical characteristics of GaN films deposited on (1120) Al2O3 substrates were found to be comparable to those of GaN films grown on (0001) Al2O3 substrates under the same growth conditions. It appears that an increment of V/III ratio allows to improve the morphological and optical properties of a GaN film deposited on the (1110) Al2O3 substrate. The best quality GaN films were achieved at a V/III ratio of 10400 with a quenched yellow luminescence and an enhanced room temperature (RT) near band edge photoluminescence (PL) emission having a linewidth of ~ 120meV0