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Title: A mathematical simulation of the effect of the bistability of current characteristics in nanosized multiple-layer heavily doped heterostructures

Abstract

Simulation methods based on the energy-balance equation are used to study the electrical conductivity of layered nanosized heterostructures in high electric fields. A quasi-hydrodynamic description of the electron drift is used with regard to the diffusion and thermal-diffusion components of the current, the divergence of the electron heat flux, and the temperature dependence of the electron mobility and energy relaxation time. Current-voltage characteristics are obtained for a layered heterostructure with a barrier height of 0.3 eV and with lengths of both the narrow-and wide-gap layers equal to 50 nm. Depending on the doping level in the range (5-1) x 10{sup 17} cm{sup -3}, the characteristics exhibit either a sharp peak of the differential conductivity or a bistability loop corresponding to the thermal-injection instability. A physical model is suggested that attributes the shape of the calculated current-voltage characteristics to the cumulative effect of the electrostatic lowering of the heterobarrier height and the increase in electron temperature near the injecting heteroboundaries.

Authors:
; ;  [1]
  1. Russian Academy of Sciences, Institute of Radio Engineering and Electronics (Russian Federation), E-mail: yamt@mail.ru
Publication Date:
OSTI Identifier:
21088101
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 41; Journal Issue: 3; Other Information: DOI: 10.1134/S1063782607030141; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; DOPED MATERIALS; ELECTRIC CONDUCTIVITY; ELECTRON DRIFT; ELECTRON MOBILITY; LAYERS; MILLI EV RANGE; NANOSTRUCTURES; SIMULATION; TEMPERATURE DEPENDENCE; THERMAL DIFFUSION

Citation Formats

Gergel', V. A., E-mail: vgergel@mail.ru, Zelenyi, A. P., and Yakupov, M. N.. A mathematical simulation of the effect of the bistability of current characteristics in nanosized multiple-layer heavily doped heterostructures. United States: N. p., 2007. Web. doi:10.1134/S1063782607030141.
Gergel', V. A., E-mail: vgergel@mail.ru, Zelenyi, A. P., & Yakupov, M. N.. A mathematical simulation of the effect of the bistability of current characteristics in nanosized multiple-layer heavily doped heterostructures. United States. doi:10.1134/S1063782607030141.
Gergel', V. A., E-mail: vgergel@mail.ru, Zelenyi, A. P., and Yakupov, M. N.. Thu . "A mathematical simulation of the effect of the bistability of current characteristics in nanosized multiple-layer heavily doped heterostructures". United States. doi:10.1134/S1063782607030141.
@article{osti_21088101,
title = {A mathematical simulation of the effect of the bistability of current characteristics in nanosized multiple-layer heavily doped heterostructures},
author = {Gergel', V. A., E-mail: vgergel@mail.ru and Zelenyi, A. P. and Yakupov, M. N.},
abstractNote = {Simulation methods based on the energy-balance equation are used to study the electrical conductivity of layered nanosized heterostructures in high electric fields. A quasi-hydrodynamic description of the electron drift is used with regard to the diffusion and thermal-diffusion components of the current, the divergence of the electron heat flux, and the temperature dependence of the electron mobility and energy relaxation time. Current-voltage characteristics are obtained for a layered heterostructure with a barrier height of 0.3 eV and with lengths of both the narrow-and wide-gap layers equal to 50 nm. Depending on the doping level in the range (5-1) x 10{sup 17} cm{sup -3}, the characteristics exhibit either a sharp peak of the differential conductivity or a bistability loop corresponding to the thermal-injection instability. A physical model is suggested that attributes the shape of the calculated current-voltage characteristics to the cumulative effect of the electrostatic lowering of the heterobarrier height and the increase in electron temperature near the injecting heteroboundaries.},
doi = {10.1134/S1063782607030141},
journal = {Semiconductors},
number = 3,
volume = 41,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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