Quantum-transport study on the impact of channel length and cross sections on variability induced by random discrete dopants in narrow gate-all-around silicon nanowire transistors

Martinez, A., Aldegunde, M., Seoane, N., Brown, A.R., Barker, J.R. and Asenov, A. (2011) Quantum-transport study on the impact of channel length and cross sections on variability induced by random discrete dopants in narrow gate-all-around silicon nanowire transistors. IEEE Transactions on Electron Devices, 58(8), pp. 2209-2217. (doi: 10.1109/TED.2011.2157929)

Full text not currently available from Enlighten.

Publisher's URL: http://dx.doi.org/10.1109/TED.2011.2157929

Abstract

In this paper, we review and extend recent work on the effect of random discrete dopants on the statistical variability in gate-all-around silicon nanowire transistors. The electron transport is described using the nonequilibrium Green's function formalism. Full 3-D real-space and coupled-mode-space representations are used. Two different cross sections (i.e., 2.2 x 2.2 and 4.2 x 4.2 nm(2)) and two different channel lengths (i.e., 6 and 12 nm) have been considered. The resistivity associated with discrete dopants can be estimated from the averaged current-voltage characteristics. The threshold-voltage variability and the sub-threshold-slope variability are reduced greatly in the transistors with longer channel length. Both are smaller at equivalent channel lengths in the 2.2 x 2.2 nm2 device due to better electrostatic integrity. At the same time, the ON-state-current variability associated with the varying resistance of the access regions is virtually independent of the channel length. However, it is reduced greatly in the 4.2 x 4.2 nm2 transistor due to a fourfold increase in the number of dopants in the access regions and corresponding self-averaging effects. Finally, we present results for the smallest transistor combining two sources of variability (i.e., discrete random dopants and surface roughness) and phonon scattering.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Barker, Professor John and Asenov, Professor Asen and Brown, Mr Andrew and Martinez, Dr Antonio
Authors: Martinez, A., Aldegunde, M., Seoane, N., Brown, A.R., Barker, J.R., and Asenov, A.
College/School:College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
Journal Name:IEEE Transactions on Electron Devices
Publisher:Institute of Electrical and Electronics Engineers
ISSN:0018-9383
ISSN (Online):1557-9646
Published Online:21 July 2011

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
530471Quantum Transport Simulations of Next Generation Field Effect TransistorsAntonio MartinezEngineering & Physical Sciences Research Council (EPSRC)EP/1004084/1Electronic and Nanoscale Engineering
443791Atomic scale simulation of nanoelectronic devicesAsen AsenovEngineering & Physical Sciences Research Council (EPSRC)EP/E038344/1Electronic and Nanoscale Engineering