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Title: Wetting of GaN islands by excess Ga: Origin of different appearances of GaN islands in scanning tunneling microscopy

Abstract

We observe three different kinds of islands, namely the 'bare', 'ghost', and 'normal' islands, by scanning tunneling microscopy of GaN(0001) prepared under Ga-rich conditions with different excess Ga coverage. They correlate to three different growth regimes. The various morphologies of the islands are suggested to be due to different states of wetting of the surface by excess Ga. The dynamical behavior of the wetting process is followed, and an island size dependence of Ga wetting is noted.

Authors:
 [1];  [2]; ;  [1];  [3]
  1. Physics Department, University of Hong Kong, Pokfulam Road, Hong Kong (China)
  2. (China)
  3. Institute of Physics, Chinese Academy of Sciences, Beijing (China)
Publication Date:
OSTI Identifier:
21045876
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 20; Other Information: DOI: 10.1103/PhysRevB.75.205310; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; GALLIUM; GALLIUM NITRIDES; LAYERS; MOLECULAR BEAM EPITAXY; MORPHOLOGY; SCANNING TUNNELING MICROSCOPY; SEMICONDUCTOR MATERIALS; SURFACE ENERGY; SURFACES

Citation Formats

Zheng Hao, Institute of Physics, Chinese Academy of Sciences, Beijing, Xie, M. H., Wu, H. S., and Xue, Q. K.. Wetting of GaN islands by excess Ga: Origin of different appearances of GaN islands in scanning tunneling microscopy. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.205310.
Zheng Hao, Institute of Physics, Chinese Academy of Sciences, Beijing, Xie, M. H., Wu, H. S., & Xue, Q. K.. Wetting of GaN islands by excess Ga: Origin of different appearances of GaN islands in scanning tunneling microscopy. United States. doi:10.1103/PHYSREVB.75.205310.
Zheng Hao, Institute of Physics, Chinese Academy of Sciences, Beijing, Xie, M. H., Wu, H. S., and Xue, Q. K.. Tue . "Wetting of GaN islands by excess Ga: Origin of different appearances of GaN islands in scanning tunneling microscopy". United States. doi:10.1103/PHYSREVB.75.205310.
@article{osti_21045876,
title = {Wetting of GaN islands by excess Ga: Origin of different appearances of GaN islands in scanning tunneling microscopy},
author = {Zheng Hao and Institute of Physics, Chinese Academy of Sciences, Beijing and Xie, M. H. and Wu, H. S. and Xue, Q. K.},
abstractNote = {We observe three different kinds of islands, namely the 'bare', 'ghost', and 'normal' islands, by scanning tunneling microscopy of GaN(0001) prepared under Ga-rich conditions with different excess Ga coverage. They correlate to three different growth regimes. The various morphologies of the islands are suggested to be due to different states of wetting of the surface by excess Ga. The dynamical behavior of the wetting process is followed, and an island size dependence of Ga wetting is noted.},
doi = {10.1103/PHYSREVB.75.205310},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 20,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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