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Indexed by:期刊论文

Date of Publication:2011-05-01

Journal:CRYSTAL RESEARCH AND TECHNOLOGY

Included Journals:Scopus、SCIE、EI

Volume:46

Issue:5

Page Number:511-516

ISSN No.:0232-1300

Key Words:nanowires; GaN; cathodoluminescence

Abstract:Ultra-long GaN nanowires have been synthesized via a simple thermal evaporation process by heating mixed GaN and Ga2O3 powders in a conventional resistance furnace under ammonia gas at 1150 degrees C. The average length of GaN nanowires is estimated to be more than 100 mu m after 30-min growth, corresponding to a fast growth rate of more than 200 mu m/h. Scanning electron microscope (SEM) observation indicated that the diameter of GaN nanowires was rather uniform along the growth direction and in the range of 100-200 nm. X-ray diffraction (XRD) and transmission electron microscope (TEM) measurements confirmed that the GaN nanowires are crystalline wurtzite-type hexagonal structure. Room-temperature cathodoluminescence (CL) measurement indicated that an obvious red-shift of the near band-edge emission peak centered at 414 nm of the ultra-long GaN nanowires and a wide shoulder in the range of 600-700 nm were observed. Possible reasons responsible for the red-shift of the near band-edge emission of the ultra-long GaN nanowires was discussed. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim