We study the effects of aluminum doping on the electronic and optical properties of ZnO, via density functional simulations. We discuss the bandstructure and absorption properties of Al:ZnO as a function of the dopant concentration, and compare with recent experimental data. Our results support the formation of a transparent conductive oxide compound up to an incorporation of Al of about 3% in substitutional Zn sites. We propose an explanation to the observed degradation of conductivity in terms of interstitial defects expected to occur at high doping concentrations, beyond the Al solubility limit.
REFERENCES
1.
J. A.
van Vechten
, in Handbook of Semiconductors
, edited by S. P.
Keller
(North-Holland
, Amsterdam
, 1980
).2.
J.
Simon
, V.
Protasenko
, C.
Lian
, H.
Xing
, and D.
Jena
, Science
327
, 60
(2010
).3.
H.
Porter
, C.
Mion
, A.
Cai
, X.
Zhang
, and J.
Muth
, Mater. Sci. Eng., B
119
, 210
(2005
).4.
M. N. E. M. S.
Tricot
, C.
Boulmer-Leborgne
, and J.
Perrière
, J. Phys. D: Appl. Phys.
41
, 175205
(2008
).5.
S. -H.
Lee
, S. -H.
Han
, H. S.
Jung
, H.
Shin
, J.
Lee
, J. -H.
Noh
, S.
Lee
, I. -S.
Cho
, J. -K.
Lee
, J.
Kim
, and H.
Shin
, J. Phys. Chem. C
114
, 7185
(2010
).6.
P.
Ágoston
, K.
Albe
, R. M.
Nieminen
, and M. J.
Puska
, Phys. Rev. Lett.
103
, 245501
(2009
).7.
S.
Lany
and A.
Zunger
, Phys. Rev. B
78
, 235104
(2008
).8.
A.
Janotti
, D.
Segev
, and C. G.
Van de Walle
, Phys. Rev. B
74
, 045202
(2006
).9.
K. -M.
Lin
, Y. -Y.
Chen
, and K. -Y.
Chou
, J. Sol-Gel Sci. Technol.
49
, 238
(2009
).10.
P.
Torelli
, private communication (September 2010
).11.
H.
Mondragón-Suárez
, A.
Maldonado
, M. de
La
, L.
Olvera
, A.
Reyes
, R.
Castanedo-Pérez
, G.
Torres-Delgrado
, and R.
Asomoza
, Appl. Surf. Sci.
193
, 52
(2002
).12.
P.
Giannozzi
, S.
Baroni
, N.
Bonini
, M.
Calandra
, R.
Car
, C.
Cavazzoni
, D.
Ceresoli
, G. L.
Chiarotti
, M.
Cococcioni
, I.
Dabo
, A. D.
Corso
, S.
de Gironcoli
, S.
Fabris
, G.
Fratesi
, R.
Gebauer
, U.
Gerstmann
, C.
Gougoussis
, A.
Kokalj
, M.
Lazzeri
, L.
Martin-Samos
, N.
Marzari
, F.
Mauri
, R.
Mazzarello
, S.
Paolini
, A.
Pasquarello
, L.
Paulatto
, C.
Sbraccia
, S.
Scandolo
, G.
Sclauzero
, A. P.
Seitsonen
, A.
Smogunov
, P.
Umari
, and R. M.
Wentzcovitche
, J. Phys.: Condens. Matter
21
, 395502
(2009
) (see also www.quantum-espresso.org).13.
J. P.
Perdew
, K.
Burke
, and M.
Ernzerhof
, Phys. Rev. Lett.
77
, 3865
(1996
).14.
D.
Vanderbilt
, Phys. Rev. B
41
, 7892
(1990
).15.
J. U.
Brehm
, M.
Winterer
, and H.
Hahn
, J. Appl. Phys.
100
, 064311
(2006
).16.
See supplementary material at http://dx.doi.org/10.1063/1.3567513 for detailed information about the dependence of EF position as a function of Al content, and optical anisotropy.
17.
P.
Palacios
, K.
Sánchez
, and P.
Wahnón
, Thin Solid Films
517
, 2448
(2009
).18.
R.
Colle
, P.
Parruccini
, A.
Benassi
, and C.
Cavazzoni
, J. Phys. Chem. B
111
, 2800
(2007
).19.
The size of the system prevents the application of many body techniques such as configuration interaction or GW-Bethe Salpether, while simulation of infinite systems does not allow the application of time dependent density functional theory. The complete simulation of the absorption spectra goes beyond the aim of this work.
20.
Y.
Dong
and L.
Brillson
, J. Electron. Mater.
37
, 743
(2008
).21.
We optimized the Hubbard correction via numerical fit of an on-site term on -states, and a on -states: the inclusion of the potential on both the anion and cation appears to be fundamental for an optimized description of interaction (Ref. 22). This sets the value of the Kohn–Sham gap to 3.1 eV, very close to the experimental one (3.3 eV). The inclusion of Hubbard correction does not change the structural and electronic properties of the doped compound.
22.
A.
Terentjevs
, A.
Catellani
, D.
Prendergast
, and G.
Cicero
, Phys. Rev. B
82
, 165307
(2010
).23.
T.
Ohgaki
, Y.
Kawamura
, T.
Kuroda
, N.
Ohashi
, Y.
Adachi
, T.
Tsurumi
, and F. M. H.
Haneda
, Key Eng. Mater.
248
, 91
(2003
).24.
© 2011 American Institute of Physics.
2011
American Institute of Physics
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