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Title: Effects of alloy disorder on the transport properties of Al{sub x}Ga{sub 1-x}N epilayers probed by persistent photoconductivity

Abstract

The effects of alloy fluctuations on the transport properties of Al{sub x}Ga{sub 1-x}N alloys (x{approx}0.35) have been probed through the use of persistent photoconductivity (PPC). In the PPC state, the electron mobility, {mu}{sub e}, as a function of electron concentration, n, in a single sample can be obtained under controlled light illumination conditions. It was found that {mu}{sub e} is a constant when n is below a critical value n{sub c} and it then increases with n at n>n{sub c}. This mobility behavior was attributed to the effects of alloy fluctuations in Al{sub x}Ga{sub 1-x}N alloys. As a result, the initial PPC buildup kinetics seen in Al{sub x}Ga{sub 1-x}N alloys was quite different from those in better understood semiconductor alloys, such as AlGaAs and ZnCdSe, and is a direct consequence of the observed unique dependence of {mu}{sub e} on n. From these measurements, the total density of the tail states below the mobility edge in the conduction band was estimated to be 1.46x10{sup 17} cm{sup -3} in a Al{sub 0.35}Ga{sub 0.65}N sample. The results were compared with those in II-VI semiconductor alloys and their implications on III-nitride device applications were discussed. (c) 2000 American Institute of Physics.

Authors:
 [1];  [1];  [1]
  1. Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601 (United States)
Publication Date:
OSTI Identifier:
20215694
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 76; Journal Issue: 13; Other Information: PBD: 27 Mar 2000
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM NITRIDES; GALLIUM NITRIDES; PHOTOCONDUCTIVITY; FLUCTUATIONS; ELECTRON MOBILITY; EXPERIMENTAL DATA

Citation Formats

Zeng, K. C., Lin, J. Y., and Jiang, H. X.. Effects of alloy disorder on the transport properties of Al{sub x}Ga{sub 1-x}N epilayers probed by persistent photoconductivity. United States: N. p., 2000. Web. doi:10.1063/1.126149.
Zeng, K. C., Lin, J. Y., & Jiang, H. X.. Effects of alloy disorder on the transport properties of Al{sub x}Ga{sub 1-x}N epilayers probed by persistent photoconductivity. United States. doi:10.1063/1.126149.
Zeng, K. C., Lin, J. Y., and Jiang, H. X.. Mon . "Effects of alloy disorder on the transport properties of Al{sub x}Ga{sub 1-x}N epilayers probed by persistent photoconductivity". United States. doi:10.1063/1.126149.
@article{osti_20215694,
title = {Effects of alloy disorder on the transport properties of Al{sub x}Ga{sub 1-x}N epilayers probed by persistent photoconductivity},
author = {Zeng, K. C. and Lin, J. Y. and Jiang, H. X.},
abstractNote = {The effects of alloy fluctuations on the transport properties of Al{sub x}Ga{sub 1-x}N alloys (x{approx}0.35) have been probed through the use of persistent photoconductivity (PPC). In the PPC state, the electron mobility, {mu}{sub e}, as a function of electron concentration, n, in a single sample can be obtained under controlled light illumination conditions. It was found that {mu}{sub e} is a constant when n is below a critical value n{sub c} and it then increases with n at n>n{sub c}. This mobility behavior was attributed to the effects of alloy fluctuations in Al{sub x}Ga{sub 1-x}N alloys. As a result, the initial PPC buildup kinetics seen in Al{sub x}Ga{sub 1-x}N alloys was quite different from those in better understood semiconductor alloys, such as AlGaAs and ZnCdSe, and is a direct consequence of the observed unique dependence of {mu}{sub e} on n. From these measurements, the total density of the tail states below the mobility edge in the conduction band was estimated to be 1.46x10{sup 17} cm{sup -3} in a Al{sub 0.35}Ga{sub 0.65}N sample. The results were compared with those in II-VI semiconductor alloys and their implications on III-nitride device applications were discussed. (c) 2000 American Institute of Physics.},
doi = {10.1063/1.126149},
journal = {Applied Physics Letters},
number = 13,
volume = 76,
place = {United States},
year = {Mon Mar 27 00:00:00 EST 2000},
month = {Mon Mar 27 00:00:00 EST 2000}
}