Release Time:2019-03-09 Hits:
Indexed by: Journal Article
Date of Publication: 2011-05-01
Journal: CRYSTAL RESEARCH AND TECHNOLOGY
Included Journals: EI、SCIE、Scopus
Volume: 46
Issue: 5
Page Number: 511-516
ISSN: 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