The University of Southampton
University of Southampton Institutional Repository

Electrodeposited Ni/Ge and germanide schottky barriers for nanoelectronics applications

Electrodeposited Ni/Ge and germanide schottky barriers for nanoelectronics applications
Electrodeposited Ni/Ge and germanide schottky barriers for nanoelectronics applications
In recent years metal/semiconductor Schottky barriers have found numerous applications in nanoelectronics. The work presented in this thesis focuses on the improvement of a few of the relevant devices using electrodeposition of metal on Ge for Schottky barrier fabrication. This low energy metallisation technique offers numerous advantages over the physical vapour deposition techniques. Electrical characteristics of the grown diodes show a high quality rectifying behaviour with extremely low leakage currents even on highly doped Ge. A non-Arrhenius behaviour of the temperature dependence is observed for the grown Ni/Ge diodes on lowly doped Ge that is explained by a spatial variation of the barrier heights. The inhomogeneity of the barrier hights is explained in line with an intrinsic surface states model for Ge. The understanding of the intrinsic surface states will help to create ohmic contacts for doped n-MOSFETs. NiGe were formed single phase by annealing. Results reveal that by using these high-quality germanide Schottky barriers as the source/drain, the subthreshold leakage currents of a Schottky barrier MOSFET could be minimised, in particular, due to the very low drain/body junction leakage current exhibited by the electrodeposited diodes. The Ni/Ge diodes on highly doped Ge show negative differential conductance at low temperature. This effect is attributed to the intervalley electron transfer in Ge conduction band to a low mobility valley. The results show experimentally that Schottky junctions could be used for hot electron injection in transferred-electron devices. A vertical Co/Ni/Si structure has been fabricated for spin injection and detection in Si. It is shown that the system functions electrically well although no magnetoresistance indicative of spin injection was observed.
Husain, Muhammad Khaled
db4ddb10-f59b-4965-8d0e-08a62f9ac0a6
Husain, Muhammad Khaled
db4ddb10-f59b-4965-8d0e-08a62f9ac0a6
De Groot, Cornelis
92cd2e02-fcc4-43da-8816-c86f966be90c

Husain, Muhammad Khaled (2009) Electrodeposited Ni/Ge and germanide schottky barriers for nanoelectronics applications. University of Southampton, School of Electronics and Computer Science, Doctoral Thesis, 156pp.

Record type: Thesis (Doctoral)

Abstract

In recent years metal/semiconductor Schottky barriers have found numerous applications in nanoelectronics. The work presented in this thesis focuses on the improvement of a few of the relevant devices using electrodeposition of metal on Ge for Schottky barrier fabrication. This low energy metallisation technique offers numerous advantages over the physical vapour deposition techniques. Electrical characteristics of the grown diodes show a high quality rectifying behaviour with extremely low leakage currents even on highly doped Ge. A non-Arrhenius behaviour of the temperature dependence is observed for the grown Ni/Ge diodes on lowly doped Ge that is explained by a spatial variation of the barrier heights. The inhomogeneity of the barrier hights is explained in line with an intrinsic surface states model for Ge. The understanding of the intrinsic surface states will help to create ohmic contacts for doped n-MOSFETs. NiGe were formed single phase by annealing. Results reveal that by using these high-quality germanide Schottky barriers as the source/drain, the subthreshold leakage currents of a Schottky barrier MOSFET could be minimised, in particular, due to the very low drain/body junction leakage current exhibited by the electrodeposited diodes. The Ni/Ge diodes on highly doped Ge show negative differential conductance at low temperature. This effect is attributed to the intervalley electron transfer in Ge conduction band to a low mobility valley. The results show experimentally that Schottky junctions could be used for hot electron injection in transferred-electron devices. A vertical Co/Ni/Si structure has been fabricated for spin injection and detection in Si. It is shown that the system functions electrically well although no magnetoresistance indicative of spin injection was observed.

Text
PhD_Thesis.pdf - Other
Download (4MB)

More information

Published date: July 2009
Organisations: University of Southampton

Identifiers

Local EPrints ID: 69056
URI: http://eprints.soton.ac.uk/id/eprint/69056
PURE UUID: 882e09ee-98b0-4146-a965-27d51b59b092
ORCID for Cornelis De Groot: ORCID iD orcid.org/0000-0002-3850-7101

Catalogue record

Date deposited: 19 Oct 2009
Last modified: 11 Dec 2021 03:43

Export record

Contributors

Author: Muhammad Khaled Husain
Thesis advisor: Cornelis De Groot ORCID iD

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×