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Title: Tailoring of the Metal-N/P-Type GaSb Interface Properties for Device Production

Abstract

There are some difficulties in producing Schottky barriers (SB) to p-type GaSb and ohmic contacts (OC) to n-type GaSb connected with the physical nature of the GaSb itself. By applying low energy Ar ion sputtering at 200-700V and (NH4)2S solution treatment of the p-type substrates we achieved a rectifying behavior of the p-GaSb/Pd contacts. The same procedure combined with a proper annealing led to the production of good n-GaSb/Pd/Ge/Au ohmic contacts. The electrical behavior of the SB and OC is inferred from their current-voltage characteristics on specially prepared diode structures. SEM and TEM investigations are conducted to specify the surface and interface reactions during the processing. We interpret these results in terms of the generation of such a Ga to Sb vacancy concentration ratio during the ion sputtering that enhances the incorporation of Ge and S as donor impurities in the GaSb surface.

Authors:
 [1];  [2];  [3];  [4]
  1. Semiconductor Physics and Technology Laboratory, St. Kl. Ohridski University, Sofia (Bulgaria)
  2. Faculty of Physics, St. Kl. Ohridski University, Sofia (Bulgaria)
  3. Aristotle University of Thessaloniki (Greece)
  4. Institute of Mineralogy and Crystallography, BAS (Bulgaria)
Publication Date:
OSTI Identifier:
21057147
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 899; Journal Issue: 1; Conference: 6. international conference of the Balkan Physical Union, Istanbul (Turkey), 22-26 Aug 2006; Other Information: DOI: 10.1063/1.2733150; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; ARGON IONS; CONCENTRATION RATIO; CRYSTALS; ELECTRIC CONDUCTIVITY; GALLIUM ANTIMONIDES; GOLD; INTERFACES; P-TYPE CONDUCTORS; PALLADIUM; SCANNING ELECTRON MICROSCOPY; SEMICONDUCTOR DEVICES; SPUTTERING; SUBSTRATES; SURFACES; TRANSMISSION ELECTRON MICROSCOPY; VACANCIES

Citation Formats

Varblianska, K., Tzeneva, S., Comninou, Ph., and Nihtianova, D. Tailoring of the Metal-N/P-Type GaSb Interface Properties for Device Production. United States: N. p., 2007. Web. doi:10.1063/1.2733150.
Varblianska, K., Tzeneva, S., Comninou, Ph., & Nihtianova, D. Tailoring of the Metal-N/P-Type GaSb Interface Properties for Device Production. United States. doi:10.1063/1.2733150.
Varblianska, K., Tzeneva, S., Comninou, Ph., and Nihtianova, D. Mon . "Tailoring of the Metal-N/P-Type GaSb Interface Properties for Device Production". United States. doi:10.1063/1.2733150.
@article{osti_21057147,
title = {Tailoring of the Metal-N/P-Type GaSb Interface Properties for Device Production},
author = {Varblianska, K. and Tzeneva, S. and Comninou, Ph. and Nihtianova, D.},
abstractNote = {There are some difficulties in producing Schottky barriers (SB) to p-type GaSb and ohmic contacts (OC) to n-type GaSb connected with the physical nature of the GaSb itself. By applying low energy Ar ion sputtering at 200-700V and (NH4)2S solution treatment of the p-type substrates we achieved a rectifying behavior of the p-GaSb/Pd contacts. The same procedure combined with a proper annealing led to the production of good n-GaSb/Pd/Ge/Au ohmic contacts. The electrical behavior of the SB and OC is inferred from their current-voltage characteristics on specially prepared diode structures. SEM and TEM investigations are conducted to specify the surface and interface reactions during the processing. We interpret these results in terms of the generation of such a Ga to Sb vacancy concentration ratio during the ion sputtering that enhances the incorporation of Ge and S as donor impurities in the GaSb surface.},
doi = {10.1063/1.2733150},
journal = {AIP Conference Proceedings},
number = 1,
volume = 899,
place = {United States},
year = {Mon Apr 23 00:00:00 EDT 2007},
month = {Mon Apr 23 00:00:00 EDT 2007}
}
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