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Title: Improving metal/semiconductor conductivity using AlO{sub x} interlayers on n-type and p-type Si

Abstract

Thermal atomic layer deposition was used to form ultra-thin interlayers in metal/interlayer/ semiconductor Ohmic contacts on n-type and p-type Si. AlO{sub x} of thickness 1–2 nm was deposited at 120 °C on Si substrates prior to metallization, forming Ni/AlO{sub x}/Si contacts. Conductivity improved by two orders of magnitude but the contacts remained rectifying. When they were annealed at 200 °C, the conductivity increased by another order of magnitude and the samples became Ohmic. A minimum specific contact resistivity of 1.5 × 10{sup −4} Ω-cm{sup 2} was obtained for structures based on lightly doped (10{sup 15 }cm{sup −3}) Si substrates. Existing models that describe Fermi level de-pinning do not fully explain our results, which are however consistent with other experimental data in the literature.

Authors:
; ; ; ; ;  [1]
  1. School of Electronic and Electrical Engineering, Newcastle University, Newcastle Upon Tyne NE17RU (United Kingdom)
Publication Date:
OSTI Identifier:
22314675
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 5; Other Information: (c) 2014 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; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINIUM OXIDES; DOPED MATERIALS; FERMI LEVEL; METALS; NICKEL; SEMICONDUCTOR MATERIALS; SILICON; SUBSTRATES

Citation Formats

King, P. J., Arac, E., Ganti, S., Kwa, K. S. K., Ponon, N., and O'Neill, A. G.. Improving metal/semiconductor conductivity using AlO{sub x} interlayers on n-type and p-type Si. United States: N. p., 2014. Web. doi:10.1063/1.4892003.
King, P. J., Arac, E., Ganti, S., Kwa, K. S. K., Ponon, N., & O'Neill, A. G.. Improving metal/semiconductor conductivity using AlO{sub x} interlayers on n-type and p-type Si. United States. doi:10.1063/1.4892003.
King, P. J., Arac, E., Ganti, S., Kwa, K. S. K., Ponon, N., and O'Neill, A. G.. Mon . "Improving metal/semiconductor conductivity using AlO{sub x} interlayers on n-type and p-type Si". United States. doi:10.1063/1.4892003.
@article{osti_22314675,
title = {Improving metal/semiconductor conductivity using AlO{sub x} interlayers on n-type and p-type Si},
author = {King, P. J. and Arac, E. and Ganti, S. and Kwa, K. S. K. and Ponon, N. and O'Neill, A. G.},
abstractNote = {Thermal atomic layer deposition was used to form ultra-thin interlayers in metal/interlayer/ semiconductor Ohmic contacts on n-type and p-type Si. AlO{sub x} of thickness 1–2 nm was deposited at 120 °C on Si substrates prior to metallization, forming Ni/AlO{sub x}/Si contacts. Conductivity improved by two orders of magnitude but the contacts remained rectifying. When they were annealed at 200 °C, the conductivity increased by another order of magnitude and the samples became Ohmic. A minimum specific contact resistivity of 1.5 × 10{sup −4} Ω-cm{sup 2} was obtained for structures based on lightly doped (10{sup 15 }cm{sup −3}) Si substrates. Existing models that describe Fermi level de-pinning do not fully explain our results, which are however consistent with other experimental data in the literature.},
doi = {10.1063/1.4892003},
journal = {Applied Physics Letters},
number = 5,
volume = 105,
place = {United States},
year = {Mon Aug 04 00:00:00 EDT 2014},
month = {Mon Aug 04 00:00:00 EDT 2014}
}
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