Microstructure of V-based ohmic contacts to AlGaN/GaN heterostructures at a reduced annealing temperature
Abstract
Ohmic contacts with V/Al/Ni/Au and V/Ni/Au metalization schemes were deposited on AlGaN/GaN heterostructures. The dependence of the specific contact resistance on the annealing conditions and the V:Al thickness ratio was shown. For an optimized electrode stack, a low specific contact resistance of 8.9 × 10{sup −6} Ω cm{sup 2} was achieved at an annealing temperature of 650 °C. Compared to the conventional Ti/Al/Ni/Au contact, this is a reduction of 150 K. The microstructure and contact formation at the AlGaN/metal interface were investigated by transmission electron microscopy including high-resolution micrographs and energy dispersive X-ray analysis. It was shown that for low-resistive contacts, the resistivity of the metalization has to be taken into account. The V:Al thickness ratio has an impact on the formation of different intermetallic phases and thus is crucial for establishing ohmic contacts at reduced annealing temperatures.
- Authors:
-
- Institute of Applied Physics, TU Bergakademie Freiberg, 09599 Freiberg (Germany)
- Namlab gGmbH, 01187 Dresden (Germany)
- Institute of Materials Science, TU Bergakademie Freiberg, 09599 Freiberg (Germany)
- Publication Date:
- OSTI Identifier:
- 22420280
- Resource Type:
- Journal Article
- Journal Name:
- Applied Physics Letters
- Additional Journal Information:
- Journal Volume: 106; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM; ALUMINIUM COMPOUNDS; ANNEALING; DEPOSITS; ELECTRIC CONDUCTIVITY; ELECTRIC CONTACTS; GALLIUM NITRIDES; GOLD; MICROSTRUCTURE; NICKEL; TRANSMISSION ELECTRON MICROSCOPY; VANADIUM; X RADIATION
Citation Formats
Schmid, A., E-mail: alexander.schmid@physik.tu-freiberg.de, Schroeter, Ch., Otto, R., Heitmann, J., Schuster, M., Klemm, V., and Rafaja, D. Microstructure of V-based ohmic contacts to AlGaN/GaN heterostructures at a reduced annealing temperature. United States: N. p., 2015.
Web. doi:10.1063/1.4907735.
Schmid, A., E-mail: alexander.schmid@physik.tu-freiberg.de, Schroeter, Ch., Otto, R., Heitmann, J., Schuster, M., Klemm, V., & Rafaja, D. Microstructure of V-based ohmic contacts to AlGaN/GaN heterostructures at a reduced annealing temperature. United States. https://doi.org/10.1063/1.4907735
Schmid, A., E-mail: alexander.schmid@physik.tu-freiberg.de, Schroeter, Ch., Otto, R., Heitmann, J., Schuster, M., Klemm, V., and Rafaja, D. 2015.
"Microstructure of V-based ohmic contacts to AlGaN/GaN heterostructures at a reduced annealing temperature". United States. https://doi.org/10.1063/1.4907735.
@article{osti_22420280,
title = {Microstructure of V-based ohmic contacts to AlGaN/GaN heterostructures at a reduced annealing temperature},
author = {Schmid, A., E-mail: alexander.schmid@physik.tu-freiberg.de and Schroeter, Ch. and Otto, R. and Heitmann, J. and Schuster, M. and Klemm, V. and Rafaja, D.},
abstractNote = {Ohmic contacts with V/Al/Ni/Au and V/Ni/Au metalization schemes were deposited on AlGaN/GaN heterostructures. The dependence of the specific contact resistance on the annealing conditions and the V:Al thickness ratio was shown. For an optimized electrode stack, a low specific contact resistance of 8.9 × 10{sup −6} Ω cm{sup 2} was achieved at an annealing temperature of 650 °C. Compared to the conventional Ti/Al/Ni/Au contact, this is a reduction of 150 K. The microstructure and contact formation at the AlGaN/metal interface were investigated by transmission electron microscopy including high-resolution micrographs and energy dispersive X-ray analysis. It was shown that for low-resistive contacts, the resistivity of the metalization has to be taken into account. The V:Al thickness ratio has an impact on the formation of different intermetallic phases and thus is crucial for establishing ohmic contacts at reduced annealing temperatures.},
doi = {10.1063/1.4907735},
url = {https://www.osti.gov/biblio/22420280},
journal = {Applied Physics Letters},
issn = {0003-6951},
number = 5,
volume = 106,
place = {United States},
year = {Mon Feb 02 00:00:00 EST 2015},
month = {Mon Feb 02 00:00:00 EST 2015}
}