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Title: Optimized growth of lattice-matched In{sub x}Al{sub 1-x}N/GaN heterostructures by molecular beam epitaxy

Abstract

The authors present a systematic study on the growth of the ternary compound In{sub x}Al{sub 1-x}N by molecular beam epitaxy. This work concentrates on In mole fractions x around 0.17, as this composition is in-plane lattice matched to GaN. At a growth temperature of 540 degree sign C, high quality material was obtained using a total metal to nitrogen flux ratio of {approx}1. Using these growth parameters, high quality GaN/InAlN superlattices were obtained without growth interruptions.

Authors:
; ; ; ;  [1];  [2]
  1. Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, New Jersey 07974 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20883266
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 2; Other Information: DOI: 10.1063/1.2430940; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM NITRIDES; CRYSTAL GROWTH; GALLIUM NITRIDES; HETEROJUNCTIONS; INDIUM NITRIDES; MOLECULAR BEAM EPITAXY; NITROGEN; SEMICONDUCTOR MATERIALS; SUPERLATTICES; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0400-1000 K

Citation Formats

Schmult, S., Siegrist, T., Sergent, A. M., Manfra, M. J., Molnar, R. J., and MIT Lincoln Laboratory, 244 Wood St., Lexington, Massachusetts 02420. Optimized growth of lattice-matched In{sub x}Al{sub 1-x}N/GaN heterostructures by molecular beam epitaxy. United States: N. p., 2007. Web. doi:10.1063/1.2430940.
Schmult, S., Siegrist, T., Sergent, A. M., Manfra, M. J., Molnar, R. J., & MIT Lincoln Laboratory, 244 Wood St., Lexington, Massachusetts 02420. Optimized growth of lattice-matched In{sub x}Al{sub 1-x}N/GaN heterostructures by molecular beam epitaxy. United States. doi:10.1063/1.2430940.
Schmult, S., Siegrist, T., Sergent, A. M., Manfra, M. J., Molnar, R. J., and MIT Lincoln Laboratory, 244 Wood St., Lexington, Massachusetts 02420. Mon . "Optimized growth of lattice-matched In{sub x}Al{sub 1-x}N/GaN heterostructures by molecular beam epitaxy". United States. doi:10.1063/1.2430940.
@article{osti_20883266,
title = {Optimized growth of lattice-matched In{sub x}Al{sub 1-x}N/GaN heterostructures by molecular beam epitaxy},
author = {Schmult, S. and Siegrist, T. and Sergent, A. M. and Manfra, M. J. and Molnar, R. J. and MIT Lincoln Laboratory, 244 Wood St., Lexington, Massachusetts 02420},
abstractNote = {The authors present a systematic study on the growth of the ternary compound In{sub x}Al{sub 1-x}N by molecular beam epitaxy. This work concentrates on In mole fractions x around 0.17, as this composition is in-plane lattice matched to GaN. At a growth temperature of 540 degree sign C, high quality material was obtained using a total metal to nitrogen flux ratio of {approx}1. Using these growth parameters, high quality GaN/InAlN superlattices were obtained without growth interruptions.},
doi = {10.1063/1.2430940},
journal = {Applied Physics Letters},
number = 2,
volume = 90,
place = {United States},
year = {Mon Jan 08 00:00:00 EST 2007},
month = {Mon Jan 08 00:00:00 EST 2007}
}
  • The electron microscopy was used to characterize the AlN interlayer in Al{sub x}Ga{sub 1-x}N/AlN/GaN heterostructures grown by plasma assisted molecular beam epitaxy (PAMBE). We show that the AlN interlayer grown by PAMBE is without gallium and oxygen incorporation and the interfaces are coherent. The AlN interlayer has the ABAB stacking of lattice planes as expected for the wurtzite phase. High purity of AlN interlayer with the ABAB stacking leads to larger conduction band offset along with stronger polarization effects. Our studies show that the origin of lower sheet resistance obtained by PAMBE is the purity of AlN interlayer.
  • In-plane anisotropic lattice relaxation was correlated with the crystal mosaicity and luminescence spectra for m-plane Al{sub x}Ga{sub 1-x}N films grown on a freestanding GaN substrate by NH{sub 3}-source molecular beam epitaxy. The homoepitaxial GaN film exhibited A- and B-excitonic emissions at 8 K, which obeyed the polarization selection rules. For Al{sub x}Ga{sub 1-x}N overlayers, the m-plane tilt mosaic along c-axis was the same as the substrate as far as coherent growth was maintained (x{<=}0.25). However, it became more severe than along the a-axis for lattice-relaxed films (x{>=}0.52). The results are explained in terms of anisotropic lattice and thermal mismatches betweenmore » the film and the substrate. Nonetheless, all the Al{sub x}Ga{sub 1-x}N films exhibited a near-band-edge emission peak and considerably weak deep emission at room temperature.« less
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