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Title: High-electron-mobility GaN grown on free-standing GaN templates by ammonia-based molecular beam epitaxy

The dependence of electron mobility on growth conditions and threading dislocation density (TDD) was studied for n{sup −}-GaN layers grown by ammonia-based molecular beam epitaxy. Electron mobility was found to strongly depend on TDD, growth temperature, and Si-doping concentration. Temperature-dependent Hall data were fit to established transport and charge-balance equations. Dislocation scattering was analyzed over a wide range of TDDs (∼2 × 10{sup 6} cm{sup −2} to ∼2 × 10{sup 10} cm{sup −2}) on GaN films grown under similar conditions. A correlation between TDD and fitted acceptor states was observed, corresponding to an acceptor state for almost every c lattice translation along each threading dislocation. Optimized GaN growth on free-standing GaN templates with a low TDD (∼2 × 10{sup 6} cm{sup −2}) resulted in electron mobilities of 1265 cm{sup 2}/Vs at 296 K and 3327 cm{sup 2}/Vs at 113 K.
Authors:
; ; ; ;  [1] ;  [2]
  1. Materials Department, University of California, Santa Barbara, California 93106 (United States)
  2. Institute of Photonics and Optoelectronics, and Department of Electrical Engineering, National Taiwan University, Taipei City 10617, Taiwan (China)
Publication Date:
OSTI Identifier:
22275519
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 19; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AMMONIA; CONCENTRATION RATIO; CORRELATIONS; CRYSTAL LATTICES; DISLOCATIONS; ELECTRON MOBILITY; GALLIUM NITRIDES; HALL EFFECT; LAYERS; MOLECULAR BEAM EPITAXY; SCATTERING; SILICON COMPOUNDS; TEMPERATURE DEPENDENCE; THIN FILMS