Hostname: page-component-848d4c4894-wg55d Total loading time: 0 Render date: 2024-05-15T05:31:25.572Z Has data issue: false hasContentIssue false

Metal Contacts to n- AlXGa1-xN

Published online by Cambridge University Press:  10 February 2011

A. Sampath
Affiliation:
Molecular Beam Epitaxy Laboratory, Dept. of Electrical and Computer Engineering and Center for Photonics Research, Boston University, 8 Saint Mary's * St., Boston, MA 02215
H. M. Ng
Affiliation:
Molecular Beam Epitaxy Laboratory, Dept. of Electrical and Computer Engineering and Center for Photonics Research, Boston University, 8 Saint Mary's * St., Boston, MA 02215
D. Korakakis
Affiliation:
Molecular Beam Epitaxy Laboratory, Dept. of Electrical and Computer Engineering and Center for Photonics Research, Boston University, 8 Saint Mary's * St., Boston, MA 02215
T. D. Moustakas
Affiliation:
Molecular Beam Epitaxy Laboratory, Dept. of Electrical and Computer Engineering and Center for Photonics Research, Boston University, 8 Saint Mary's * St., Boston, MA 02215
Get access

Abstract

In this paper we report on the formation of ohmic contacts to n- AlxGa1-xN alloys. The films were produced by plasma-assisted MBE and doped n- type with silicon at doping levels between 1018 to 1019 cm-3. Contacts were formed by sequential deposition of 200 Å of Ti and 2000 Å of Al and the contact resistivities were determined from TLM measurements. For low Al- content (x<. 10) the I-V characteristics are linear with contact resistivities of between 10-4 to 10-5 cm2. The contacts become progressively non-ohmic at Al concentrations greater than 10%. There results are consistent with the Schottky limit being applicable to these alloys and thus the Ti/Al contact forms Schottky barriers with higher barrier height as the conduction band of the alloy moves towards the vacuum level.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

*

now at the University of Nottingham

References

1. Foresi, J., Moustakas, T.D, “Metal contacts to gallium nitride,” Appl. Phys. Lett., 62, 2859 (1993)Google Scholar
2. Dhesi, Sarnjeet S., Stagarescu, Cristian B., Smith, Kevin, Doppolapudi, D., Singh, R. and Moustakas, T.D., “Surface and Bulk Electronic Structure of Thin Film Wurtzite GaN” Physica Review B (1997)Google Scholar
3. Sampath, A., Thesis, M.S., Boston University, 1996.Google Scholar
4. Gan, Zhifang, Mohammad, S. Noor, Kim, Wook, Aktas, Özgür, Botchkarev, Andrei E., Morkoç, H., “Very low resistance multilayer ohmic contact to n-GaN,” AppL Phys. Lett., 68, 1672 (1996)Google Scholar
5. Guo, J.D., Lin, C.I., Feng, M.S., Pan, F. M, Chi, G.C., Lee, C. T, “A bilayer Ti/Ag ohmic contact for highly doped n-type GaN films,” AppL Phys Lett., 68, 235 (1996).Google Scholar
6.. Schetzina, , MRS Symp. Proc. 395, 123 (1996)Google Scholar