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Title: Metalorganic chemical vapor deposition growth of high-mobility AlGaN/AlN/GaN heterostructures on GaN templates and native GaN substrates

Abstract

Severe surface decomposition of semi-insulating (SI) GaN templates occurred in high-temperature H{sub 2} atmosphere prior to epitaxial growth in a metalorganic chemical vapor deposition system. A two-step heating process with a surface stabilization technique was developed to preserve the GaN template surface. Utilizing the optimized heating process, a high two-dimensional electron gas mobility ∼2000 cm{sup 2}/V·s was obtained in a thin AlGaN/AlN/GaN heterostructure with an only 100-nm-thick GaN spacer layer homoepitaxially grown on the GaN template. This technique was also demonstrated viable for native GaN substrates to stabilize the surface facilitating two-dimensional growth of GaN layers. Very high residual silicon and oxygen concentrations were found up to ∼1 × 10{sup 20 }cm{sup −3} at the interface between the GaN epilayer and the native GaN substrate. Capacitance-voltage measurements confirmed that the residual carbon doping controlled by growth conditions of the GaN epilayer can be used to successfully compensate the donor-like impurities. State-of-the-art structural properties of a high-mobility AlGaN/AlN/GaN heterostructure was then realized on a 1 × 1 cm{sup 2} SI native GaN substrate; the full width at half maximum of the X-ray rocking curves of the GaN (002) and (102) peaks are only 21 and 14 arc sec, respectively. The surface morphology of the heterostructure shows uniform parallel bilayermore » steps, and no morphological defects were noticeable over the entire epi-wafer.« less

Authors:
; ; ;  [1]
  1. Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE 581 83 Linköping (Sweden)
Publication Date:
OSTI Identifier:
22413183
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 8; Other Information: (c) 2015 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; ALUMINIUM NITRIDES; CAPACITANCE; CARBON; CHEMICAL VAPOR DEPOSITION; CONCENTRATION RATIO; ELECTRIC POTENTIAL; ELECTRON GAS; EPITAXY; GALLIUM NITRIDES; INTERFACES; LAYERS; MORPHOLOGY; OXYGEN; SILICON; SUBSTRATES; SURFACES; TWO-DIMENSIONAL SYSTEMS; X-RAY DIFFRACTION

Citation Formats

Chen, Jr-Tai, E-mail: jrche@ifm.liu.se, Hsu, Chih-Wei, Forsberg, Urban, and Janzén, Erik. Metalorganic chemical vapor deposition growth of high-mobility AlGaN/AlN/GaN heterostructures on GaN templates and native GaN substrates. United States: N. p., 2015. Web. doi:10.1063/1.4913223.
Chen, Jr-Tai, E-mail: jrche@ifm.liu.se, Hsu, Chih-Wei, Forsberg, Urban, & Janzén, Erik. Metalorganic chemical vapor deposition growth of high-mobility AlGaN/AlN/GaN heterostructures on GaN templates and native GaN substrates. United States. doi:10.1063/1.4913223.
Chen, Jr-Tai, E-mail: jrche@ifm.liu.se, Hsu, Chih-Wei, Forsberg, Urban, and Janzén, Erik. Sat . "Metalorganic chemical vapor deposition growth of high-mobility AlGaN/AlN/GaN heterostructures on GaN templates and native GaN substrates". United States. doi:10.1063/1.4913223.
@article{osti_22413183,
title = {Metalorganic chemical vapor deposition growth of high-mobility AlGaN/AlN/GaN heterostructures on GaN templates and native GaN substrates},
author = {Chen, Jr-Tai, E-mail: jrche@ifm.liu.se and Hsu, Chih-Wei and Forsberg, Urban and Janzén, Erik},
abstractNote = {Severe surface decomposition of semi-insulating (SI) GaN templates occurred in high-temperature H{sub 2} atmosphere prior to epitaxial growth in a metalorganic chemical vapor deposition system. A two-step heating process with a surface stabilization technique was developed to preserve the GaN template surface. Utilizing the optimized heating process, a high two-dimensional electron gas mobility ∼2000 cm{sup 2}/V·s was obtained in a thin AlGaN/AlN/GaN heterostructure with an only 100-nm-thick GaN spacer layer homoepitaxially grown on the GaN template. This technique was also demonstrated viable for native GaN substrates to stabilize the surface facilitating two-dimensional growth of GaN layers. Very high residual silicon and oxygen concentrations were found up to ∼1 × 10{sup 20 }cm{sup −3} at the interface between the GaN epilayer and the native GaN substrate. Capacitance-voltage measurements confirmed that the residual carbon doping controlled by growth conditions of the GaN epilayer can be used to successfully compensate the donor-like impurities. State-of-the-art structural properties of a high-mobility AlGaN/AlN/GaN heterostructure was then realized on a 1 × 1 cm{sup 2} SI native GaN substrate; the full width at half maximum of the X-ray rocking curves of the GaN (002) and (102) peaks are only 21 and 14 arc sec, respectively. The surface morphology of the heterostructure shows uniform parallel bilayer steps, and no morphological defects were noticeable over the entire epi-wafer.},
doi = {10.1063/1.4913223},
journal = {Journal of Applied Physics},
number = 8,
volume = 117,
place = {United States},
year = {Sat Feb 28 00:00:00 EST 2015},
month = {Sat Feb 28 00:00:00 EST 2015}
}