Rode's iterative calculation of surface optical phonon scattering limited electron mobility in Npolar GaN devices
Abstract
Npolar GaN channel mobility is important for high frequency device applications. Here, we report theoretical calculations on the surface optical (SO) phonon scattering rate of twodimensional electron gas (2DEG) in Npolar GaN quantum well channels with highk dielectrics. Rode's iterative calculation is used to predict the scattering rate and mobility. Coupling of the GaN plasmon modes with the SO modes is taken into account and dynamic screening is employed under linear polarization response. The effect of SO phonons on 2DEG mobility was found to be small at >5 nm channel thickness. However, the SO mobility in 3 nm Npolar GaN channels with HfO{sub 2} and ZrO{sub 2} highk dielectrics is low and limits the total mobility. The SO scattering for SiN dielectric on GaN was found to be negligible due to its high SO phonon energy. Using Al{sub 2}O{sub 3}, the SO phonon scattering does not affect mobility significantly only except the case when the channel is too thin with a low 2DEG density.
 Authors:
 Electrical Engineering Department, University at Buffalo, Buffalo, New York 14260 (United States)
 Publication Date:
 OSTI Identifier:
 22413120
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 6; 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; 77 NANOSCIENCE AND NANOTECHNOLOGY; ALUMINIUM OXIDES; COUPLING; DIELECTRIC MATERIALS; ELECTRON GAS; ELECTRON MOBILITY; GALLIUM NITRIDES; HAFNIUM OXIDES; ITERATIVE METHODS; PHONONS; PLASMONS; POLARIZATION; QUANTUM WELLS; SILICON NITRIDES; SURFACES; TWODIMENSIONAL SYSTEMS; ZIRCONIUM OXIDES
Citation Formats
Ghosh, Krishnendu, Email: kghosh3@buffalo.edu, and Singisetti, Uttam, Email: uttamsin@buffalo.edu. Rode's iterative calculation of surface optical phonon scattering limited electron mobility in Npolar GaN devices. United States: N. p., 2015.
Web. doi:10.1063/1.4907800.
Ghosh, Krishnendu, Email: kghosh3@buffalo.edu, & Singisetti, Uttam, Email: uttamsin@buffalo.edu. Rode's iterative calculation of surface optical phonon scattering limited electron mobility in Npolar GaN devices. United States. doi:10.1063/1.4907800.
Ghosh, Krishnendu, Email: kghosh3@buffalo.edu, and Singisetti, Uttam, Email: uttamsin@buffalo.edu. 2015.
"Rode's iterative calculation of surface optical phonon scattering limited electron mobility in Npolar GaN devices". United States.
doi:10.1063/1.4907800.
@article{osti_22413120,
title = {Rode's iterative calculation of surface optical phonon scattering limited electron mobility in Npolar GaN devices},
author = {Ghosh, Krishnendu, Email: kghosh3@buffalo.edu and Singisetti, Uttam, Email: uttamsin@buffalo.edu},
abstractNote = {Npolar GaN channel mobility is important for high frequency device applications. Here, we report theoretical calculations on the surface optical (SO) phonon scattering rate of twodimensional electron gas (2DEG) in Npolar GaN quantum well channels with highk dielectrics. Rode's iterative calculation is used to predict the scattering rate and mobility. Coupling of the GaN plasmon modes with the SO modes is taken into account and dynamic screening is employed under linear polarization response. The effect of SO phonons on 2DEG mobility was found to be small at >5 nm channel thickness. However, the SO mobility in 3 nm Npolar GaN channels with HfO{sub 2} and ZrO{sub 2} highk dielectrics is low and limits the total mobility. The SO scattering for SiN dielectric on GaN was found to be negligible due to its high SO phonon energy. Using Al{sub 2}O{sub 3}, the SO phonon scattering does not affect mobility significantly only except the case when the channel is too thin with a low 2DEG density.},
doi = {10.1063/1.4907800},
journal = {Journal of Applied Physics},
number = 6,
volume = 117,
place = {United States},
year = 2015,
month = 2
}

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