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Title: Low-temperature synthesis of gallium nitride thin films using electron cyclotron resonance plasma assisted pulsed laser deposition from a GaAs target

Abstract

Using reactive pulsed laser deposition assisted by electron cyclotron resonance (ECR) plasma, we have synthesized GaN thin films from a polycrystalline GaAs target at low temperatures. This was achieved by ablating the GaAs target in the reactive environment of a nitrogen plasma generated from ECR microwave discharge in pure nitrogen gas and depositing the films with concurrent bombardment by the low-energy nitrogen plasma stream. High-energy ion backscattering spectroscopy analysis shows that the synthesized films are gallium rich. Characterizations by x-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy confirm the presence of GaN bonds in the films. The recorded absorption spectrum also reveals GaN stretching mode characteristic of the hexagonal GaN phase. The synthesized GaN films are transparent in the visible region and have a band gap of 3.38 eV. Optical emission from the plume during film deposition reveals that the plume created by pulsed laser ablation of the GaAs target consists mainly of monoatomic atoms and ions of gallium and arsenic. Mechanisms responsible for the formation of GaN molecules and the growth of GaN films are also discussed.

Authors:
; ; ; ; ; ; ;  [1];  [2]
  1. State Key Laboratory for Advanced Photonic Materials and Devices, Department of Optical Science and Engineering, Fudan University, Shanghai 200433 (China)
  2. (China)
Publication Date:
OSTI Identifier:
20723210
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 23; Journal Issue: 6; Other Information: DOI: 10.1116/1.2091093; (c) 2005 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION SPECTRA; ARSENIC IONS; BACKSCATTERING; CRYSTAL GROWTH; ELECTRON CYCLOTRON-RESONANCE; ENERGY BEAM DEPOSITION; EV RANGE 01-10; FOURIER TRANSFORM SPECTROMETERS; GALLIUM ARSENIDES; GALLIUM IONS; GALLIUM NITRIDES; HIGH-FREQUENCY DISCHARGES; INFRARED SPECTRA; LASER RADIATION; NITROGEN; PLASMA; POLYCRYSTALS; PULSED IRRADIATION; THIN FILMS; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Sun, J., Wu, A.M., Xu, N., Ying, Z.F., Shen, X.K., Dong, Z.B., Wu, J.D., Shi, L.Q., and Institute of Modern Physics, Fudan University, Shanghai 200433. Low-temperature synthesis of gallium nitride thin films using electron cyclotron resonance plasma assisted pulsed laser deposition from a GaAs target. United States: N. p., 2005. Web. doi:10.1116/1.2091093.
Sun, J., Wu, A.M., Xu, N., Ying, Z.F., Shen, X.K., Dong, Z.B., Wu, J.D., Shi, L.Q., & Institute of Modern Physics, Fudan University, Shanghai 200433. Low-temperature synthesis of gallium nitride thin films using electron cyclotron resonance plasma assisted pulsed laser deposition from a GaAs target. United States. doi:10.1116/1.2091093.
Sun, J., Wu, A.M., Xu, N., Ying, Z.F., Shen, X.K., Dong, Z.B., Wu, J.D., Shi, L.Q., and Institute of Modern Physics, Fudan University, Shanghai 200433. Tue . "Low-temperature synthesis of gallium nitride thin films using electron cyclotron resonance plasma assisted pulsed laser deposition from a GaAs target". United States. doi:10.1116/1.2091093.
@article{osti_20723210,
title = {Low-temperature synthesis of gallium nitride thin films using electron cyclotron resonance plasma assisted pulsed laser deposition from a GaAs target},
author = {Sun, J. and Wu, A.M. and Xu, N. and Ying, Z.F. and Shen, X.K. and Dong, Z.B. and Wu, J.D. and Shi, L.Q. and Institute of Modern Physics, Fudan University, Shanghai 200433},
abstractNote = {Using reactive pulsed laser deposition assisted by electron cyclotron resonance (ECR) plasma, we have synthesized GaN thin films from a polycrystalline GaAs target at low temperatures. This was achieved by ablating the GaAs target in the reactive environment of a nitrogen plasma generated from ECR microwave discharge in pure nitrogen gas and depositing the films with concurrent bombardment by the low-energy nitrogen plasma stream. High-energy ion backscattering spectroscopy analysis shows that the synthesized films are gallium rich. Characterizations by x-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy confirm the presence of GaN bonds in the films. The recorded absorption spectrum also reveals GaN stretching mode characteristic of the hexagonal GaN phase. The synthesized GaN films are transparent in the visible region and have a band gap of 3.38 eV. Optical emission from the plume during film deposition reveals that the plume created by pulsed laser ablation of the GaAs target consists mainly of monoatomic atoms and ions of gallium and arsenic. Mechanisms responsible for the formation of GaN molecules and the growth of GaN films are also discussed.},
doi = {10.1116/1.2091093},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 6,
volume = 23,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
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