skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Electron mobility in very low density GaN/AlGaN/GaN heterostructures

Journal Article · · Applied Physics Letters
DOI:https://doi.org/10.1063/1.1784887· OSTI ID:20632773
; ; ; ;  [1]
  1. Bell Laboratories, Lucent Technologies, 700 Mountain Avenue, Murray Hill, New Jersey 07974 (United States)

We report on the transport properties of a tunable two-dimensional electron gas (2DEG) confined at the lower interface of a GaN/Al{sub 0.06}Ga{sub 0.94}N/GaN heterostructure grown by plasma-assisted molecular beam epitaxy on semi-insulating GaN templates prepared by hydride vapor phase epitaxy. Using an insulated gate Hall bar structure, the electron density is continuously tuned from {approx}2x10{sup 12} down to 1.5x10{sup 11} cm{sup -2}. At T=300 mK, the 2DEG displays a maximum mobility of 80 000 cm{sup 2}/V s at a sheet density of 1.75x10{sup 12} cm{sup -2}. At low densities, the mobility exhibits a power law dependence on density -{mu}{approx}n{sub e}{sup {alpha}}, with {alpha}{approx}1.0, over the range of 2x10{sup 11}-1x10{sup 12} cm{sup -2}. In this density regime, the mobility is no longer limited by alloy scattering and long-range Coulomb scattering dominates. We discuss the dominant scattering mechanisms that presently limit low temperature mobility at electron densities below 1x10{sup 12} cm{sup -2}.

OSTI ID:
20632773
Journal Information:
Applied Physics Letters, Vol. 85, Issue 10; Other Information: DOI: 10.1063/1.1784887; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
Country of Publication:
United States
Language:
English