Computational testing of trivalent dopants in CeO2 for improved high-kappa dielectric behaviour
Citation:
Keating, PRL, Scanlon, DO, Watson, GW, Computational testing of trivalent dopants in CeO2 for improved high-kappa dielectric behaviour, Journal of Materials Chemistry C, 1, 2013, 1093-1098Download Item:
c2tc00385f.pdf (Published (publisher's copy) - Peer Reviewed) 335.7Kb
Abstract:
Due to its high dielectric constant, large band gap, and very small lattice mismatch with Si, CeO
2
has been
proposed as a promising candidate high-
k
dielectric material. The performance of CeO
2
as a dielectric
material, however, is severely limited due its propensity for facile reduction (oxygen vacancy formation),
which causes a high interface state density, and subsequent decreased drain currents. In this article we
use density functional theory (DFT) to screen for trivalent dopants which could decrease the
concentration of defects in CeO
2
samples. We demonstrate that La and Y are the most soluble trivalent
dopants in CeO
2
, and can reduce the number of the electrons in the system both ionically (formation of
[M
Ce
?
V
O
?
M
Ce
] clusters) or to a lesser extent electronically (hole formation). La doping also increases the
lattice constant of CeO
2
, improving the lattice match with Si
Sponsor
Grant Number
Engineering and Physical Sciences Research Council (EPSRC)
EP/F067496
Science Foundation Ireland (SFI)
09/RFP/MTR2274
Science Foundation Ireland (SFI)
08/RFP/MTR1044
Author's Homepage:
http://people.tcd.ie/watsongDescription:
PUBLISHED
Author: WATSON, GRAEME
Type of material:
Journal ArticleCollections:
Series/Report no:
Journal of Materials Chemistry C1
Availability:
Full text availableKeywords:
Si, CeO 2DOI:
http://dx.doi.org/10.1039/c2tc00385fLicences: