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Title: Atomic layer deposition of GaN at low temperatures

The authors report on the self-limiting growth of GaN thin films at low temperatures. Films were deposited on Si substrates by plasma-enhanced atomic layer deposition using trimethylgallium (TMG) and ammonia (NH{sub 3}) as the group-III and -V precursors, respectively. GaN deposition rate saturated at 185 deg. C for NH{sub 3} doses starting from 90 s. Atomic layer deposition temperature window was observed from 185 to {approx}385 deg. C. Deposition rate, which is constant at {approx}0.51 A/cycle within the temperature range of 250 - 350 deg. C, increased slightly as the temperature decreased to 185 deg. C. In the bulk film, concentrations of Ga, N, and O were constant at {approx}36.6, {approx}43.9, and {approx}19.5 at. %, respectively. C was detected only at the surface and no C impurities were found in the bulk film. High oxygen concentration in films was attributed to the oxygen impurities present in group-V precursor. High-resolution transmission electron microscopy studies revealed a microstructure consisting of small crystallites dispersed in an amorphous matrix.
Authors:
; ; ;  [1]
  1. UNAM - Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara (Turkey)
Publication Date:
OSTI Identifier:
22054135
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films; Journal Volume: 30; Journal Issue: 1; Other Information: (c) 2012 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMMONIA; CRYSTAL GROWTH; DOSES; GALLIUM COMPOUNDS; GALLIUM NITRIDES; MICROSTRUCTURE; NITROGEN; OXYGEN; PLASMA; PRECURSOR; SILICON; SUBSTRATES; TEMPERATURE RANGE 0065-0273 K; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY