The University of Southampton
University of Southampton Institutional Repository
Warning ePrints Soton is experiencing an issue with some file downloads not being available. We are working hard to fix this. Please bear with us.

Access resistance reduction in Ge nanowires and substrates based on non-destructive gas-source dopant in-diffusion

Access resistance reduction in Ge nanowires and substrates based on non-destructive gas-source dopant in-diffusion
Access resistance reduction in Ge nanowires and substrates based on non-destructive gas-source dopant in-diffusion
To maintain semiconductor device scaling, in recent years industry has been forced to move from planar to non-planar device architectures. This alone has created the need to develop a radically new, non-destructive method for doping. Doping alters the electrical properties of a semiconductor, related to the access resistance. Low access resistance is necessary for high performance technology and reduced power consumption. In this work the authors reduced access resistance in top-down patterned Ge nanowires and Ge substrates by a non-destructive dopant in-diffusion process. Furthermore, an innovative electrical characterisation methodology is developed for nanowire and fin-based test structures to extract important parameters that are related to access resistance such as nanowire resistivity, sheet resistance, and active doping levels. Phosphine or arsine was flowed in a Metalorganic Vapour Phase Epitaxy reactor over heated Ge samples in the range of 650-700 °C. Dopants were incorporated and activated in this single step. No Ge growth accompanied this process. Active doping levels were determined by electrochemical capacitance-voltage free carrier profiling to be in the range of 1019 cm-3. The nanowires were patterned in an array of widths from 20-1000 nm. Cross-sectional Transmission Electron Microscopy of the doped nanowires showed minimal crystal damage. Electrical characterisation of the Ge nanowires was performed to contrast doping activation in thin-body structures with that in bulk substrates. Despite the high As dose incorporation on unpatterned samples, the nanowire analysis determined that the P-based process was the better choice for scaled features.
2050-7526
9248-9257
Duffy, Ray
4f7f6149-f935-412e-a913-bf79df5361f3
Shayesteh, Maryam
660d4bbc-ec8a-4cde-81d7-4f0f5f61bb98
Thomas, Kevin
d294a7c1-ddea-4551-b386-e3aebbdc691d
Pelucchi, Emanuele
309a2249-8496-4ecd-81c0-95b4af6d3fa5
Yu, Ran
5249c244-62ef-4a65-8402-8c73155b9c48
Gangnaik, Anushka
8b44e462-2a3f-4295-a9ff-1a2f7c09f14d
Georgiev, Yordan M.
75581277-0154-4144-8a94-36eaffeeef02
Carolan, Patrick
b813a9a4-1814-41c3-8e8b-c43b90bc31cb
Petkov, Nikolay
4243e25a-7819-4fa7-afb4-30a86d8b96be
Long, Brenda
80d19092-b52c-40e4-be6f-e0bd4872bcaf
Holmes, Justin D.
6f16ad07-0c95-4eba-a71b-70dd149f5a9a
Duffy, Ray
4f7f6149-f935-412e-a913-bf79df5361f3
Shayesteh, Maryam
660d4bbc-ec8a-4cde-81d7-4f0f5f61bb98
Thomas, Kevin
d294a7c1-ddea-4551-b386-e3aebbdc691d
Pelucchi, Emanuele
309a2249-8496-4ecd-81c0-95b4af6d3fa5
Yu, Ran
5249c244-62ef-4a65-8402-8c73155b9c48
Gangnaik, Anushka
8b44e462-2a3f-4295-a9ff-1a2f7c09f14d
Georgiev, Yordan M.
75581277-0154-4144-8a94-36eaffeeef02
Carolan, Patrick
b813a9a4-1814-41c3-8e8b-c43b90bc31cb
Petkov, Nikolay
4243e25a-7819-4fa7-afb4-30a86d8b96be
Long, Brenda
80d19092-b52c-40e4-be6f-e0bd4872bcaf
Holmes, Justin D.
6f16ad07-0c95-4eba-a71b-70dd149f5a9a

Duffy, Ray, Shayesteh, Maryam, Thomas, Kevin, Pelucchi, Emanuele, Yu, Ran, Gangnaik, Anushka, Georgiev, Yordan M., Carolan, Patrick, Petkov, Nikolay, Long, Brenda and Holmes, Justin D. (2014) Access resistance reduction in Ge nanowires and substrates based on non-destructive gas-source dopant in-diffusion. Journal of Materials Chemistry C, 2 (43), 9248-9257. (doi:10.1039/c4tc02018a).

Record type: Article

Abstract

To maintain semiconductor device scaling, in recent years industry has been forced to move from planar to non-planar device architectures. This alone has created the need to develop a radically new, non-destructive method for doping. Doping alters the electrical properties of a semiconductor, related to the access resistance. Low access resistance is necessary for high performance technology and reduced power consumption. In this work the authors reduced access resistance in top-down patterned Ge nanowires and Ge substrates by a non-destructive dopant in-diffusion process. Furthermore, an innovative electrical characterisation methodology is developed for nanowire and fin-based test structures to extract important parameters that are related to access resistance such as nanowire resistivity, sheet resistance, and active doping levels. Phosphine or arsine was flowed in a Metalorganic Vapour Phase Epitaxy reactor over heated Ge samples in the range of 650-700 °C. Dopants were incorporated and activated in this single step. No Ge growth accompanied this process. Active doping levels were determined by electrochemical capacitance-voltage free carrier profiling to be in the range of 1019 cm-3. The nanowires were patterned in an array of widths from 20-1000 nm. Cross-sectional Transmission Electron Microscopy of the doped nanowires showed minimal crystal damage. Electrical characterisation of the Ge nanowires was performed to contrast doping activation in thin-body structures with that in bulk substrates. Despite the high As dose incorporation on unpatterned samples, the nanowire analysis determined that the P-based process was the better choice for scaled features.

Text
c4tc02018a - Version of Record
Restricted to Repository staff only
Request a copy

More information

Published date: 21 November 2014

Identifiers

Local EPrints ID: 453423
URI: http://eprints.soton.ac.uk/id/eprint/453423
ISSN: 2050-7526
PURE UUID: 0b85120c-c90c-47ff-baec-77f3b5aac020

Catalogue record

Date deposited: 14 Jan 2022 17:36
Last modified: 14 Jan 2022 17:37

Export record

Altmetrics

Contributors

Author: Ray Duffy
Author: Maryam Shayesteh
Author: Kevin Thomas
Author: Emanuele Pelucchi
Author: Ran Yu
Author: Anushka Gangnaik
Author: Yordan M. Georgiev
Author: Patrick Carolan
Author: Nikolay Petkov
Author: Brenda Long
Author: Justin D. Holmes

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.

×