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Title: Structural and band alignment properties of Al{sub 2}O{sub 3} on epitaxial Ge grown on (100), (110), and (111)A GaAs substrates by molecular beam epitaxy

Abstract

Structural and band alignment properties of atomic layer Al{sub 2}O{sub 3} oxide film deposited on crystallographically oriented epitaxial Ge grown in-situ on (100), (110), and (111)A GaAs substrates using two separate molecular beam epitaxy chambers were investigated using cross-sectional transmission microscopy (TEM) and x-ray photoelectron spectroscopy (XPS). High-resolution triple axis x-ray measurement demonstrated pseudomorphic and high-quality Ge epitaxial layer on crystallographically oriented GaAs substrates. The cross-sectional TEM exhibited a sharp interface between the Ge epilayer and each orientation of the GaAs substrate as well as the Al{sub 2}O{sub 3} film and the Ge epilayer. The extracted valence band offset, {Delta}E{sub v}, values of Al{sub 2}O{sub 3} relative to (100), (110), and (111) Ge orientations using XPS measurement were 3.17 eV, 3.34 eV, and 3.10 eV, respectively. Using XPS data, variations in {Delta}E{sub v} related to the crystallographic orientation were {Delta}E{sub V}(110)Ge>{Delta}E{sub V}(100)Ge{>=}{Delta}E{sub V}(111)Ge and the conduction band offset, {Delta}E{sub c}, related to the crystallographic orientation was {Delta}E{sub c}(111)Ge>{Delta}E{sub c}(110)Ge>{Delta}E{sub c}(100)Ge using the measured {Delta}E{sub v}, bandgap of Al{sub 2}O{sub 3} in each orientation, and well-known Ge bandgap of 0.67 eV. These band offset parameters are important for future application of Ge-based p- and n-channel metal-oxide field-effect transistor design.

Authors:
;  [1]; ;  [2];  [3];  [4]; ;  [5]
  1. Advanced Devices and Sustainable Energy Laboratory (ADSEL), Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)
  2. Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States)
  3. Department of Biomedical Engineering and Department of Mechanical Engineering, University of Bridgeport, Bridgeport, Connecticut 06604 (United States)
  4. Department of Chemical and Biomolecular Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269 (United States)
  5. Department of Electrical and Computer Engineering, University of Bridgeport, Bridgeport, Connecticut 06604 (United States)
Publication Date:
OSTI Identifier:
22102334
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 113; Journal Issue: 13; Other Information: (c) 2013 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM OXIDES; CRYSTALLOGRAPHY; ENERGY GAP; FIELD EFFECT TRANSISTORS; FILMS; GALLIUM ARSENIDES; GERMANIUM; INTERFACES; LAYERS; METALS; MOLECULAR BEAM EPITAXY; RESOLUTION; SUBSTRATES; TRANSMISSION; TRANSMISSION ELECTRON MICROSCOPY; X RADIATION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Hudait, M. K., Zhu, Y., Maurya, D., Priya, S., Patra, P. K., Ma, A. W. K., Aphale, A., and Macwan, I. Structural and band alignment properties of Al{sub 2}O{sub 3} on epitaxial Ge grown on (100), (110), and (111)A GaAs substrates by molecular beam epitaxy. United States: N. p., 2013. Web. doi:10.1063/1.4799367.
Hudait, M. K., Zhu, Y., Maurya, D., Priya, S., Patra, P. K., Ma, A. W. K., Aphale, A., & Macwan, I. Structural and band alignment properties of Al{sub 2}O{sub 3} on epitaxial Ge grown on (100), (110), and (111)A GaAs substrates by molecular beam epitaxy. United States. https://doi.org/10.1063/1.4799367
Hudait, M. K., Zhu, Y., Maurya, D., Priya, S., Patra, P. K., Ma, A. W. K., Aphale, A., and Macwan, I. 2013. "Structural and band alignment properties of Al{sub 2}O{sub 3} on epitaxial Ge grown on (100), (110), and (111)A GaAs substrates by molecular beam epitaxy". United States. https://doi.org/10.1063/1.4799367.
@article{osti_22102334,
title = {Structural and band alignment properties of Al{sub 2}O{sub 3} on epitaxial Ge grown on (100), (110), and (111)A GaAs substrates by molecular beam epitaxy},
author = {Hudait, M. K. and Zhu, Y. and Maurya, D. and Priya, S. and Patra, P. K. and Ma, A. W. K. and Aphale, A. and Macwan, I.},
abstractNote = {Structural and band alignment properties of atomic layer Al{sub 2}O{sub 3} oxide film deposited on crystallographically oriented epitaxial Ge grown in-situ on (100), (110), and (111)A GaAs substrates using two separate molecular beam epitaxy chambers were investigated using cross-sectional transmission microscopy (TEM) and x-ray photoelectron spectroscopy (XPS). High-resolution triple axis x-ray measurement demonstrated pseudomorphic and high-quality Ge epitaxial layer on crystallographically oriented GaAs substrates. The cross-sectional TEM exhibited a sharp interface between the Ge epilayer and each orientation of the GaAs substrate as well as the Al{sub 2}O{sub 3} film and the Ge epilayer. The extracted valence band offset, {Delta}E{sub v}, values of Al{sub 2}O{sub 3} relative to (100), (110), and (111) Ge orientations using XPS measurement were 3.17 eV, 3.34 eV, and 3.10 eV, respectively. Using XPS data, variations in {Delta}E{sub v} related to the crystallographic orientation were {Delta}E{sub V}(110)Ge>{Delta}E{sub V}(100)Ge{>=}{Delta}E{sub V}(111)Ge and the conduction band offset, {Delta}E{sub c}, related to the crystallographic orientation was {Delta}E{sub c}(111)Ge>{Delta}E{sub c}(110)Ge>{Delta}E{sub c}(100)Ge using the measured {Delta}E{sub v}, bandgap of Al{sub 2}O{sub 3} in each orientation, and well-known Ge bandgap of 0.67 eV. These band offset parameters are important for future application of Ge-based p- and n-channel metal-oxide field-effect transistor design.},
doi = {10.1063/1.4799367},
url = {https://www.osti.gov/biblio/22102334}, journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 13,
volume = 113,
place = {United States},
year = {2013},
month = {4}
}