We present the chemical and structural optimization of ultrathin magnetic oxide EuO films on silicon. By applying a controlled in situ passivation of the Si(001) surface with SiOx in the monolayer regime, metallic silicide contaminations at the interface can be effectively reduced down to a sub-monolayer coverage, as was carefully quantified by interface-sensitive hard x-ray photoemission spectroscopy. Heteroepitaxial growth of EuO on Si(001) is sustained for this ultrathin SiOx-passivation, and bulk-near magnetic properties are observed for the 4 nm-thin EuO films. Our successful combination of chemically and structurally optimized EuO/Si(001) heterostructures by ultrathin in situ SiOx passivation makes this system promising for an application as alternative spin functional tunnel contacts in spin-FETs.

1.
R.
Jansen
 et al.,
Semicond. Sci. Technol.
27
,
083001
(
2012
).
2.
S.
Bader
 et al.,
Annu. Rev. Condens. Matter Phys.
1
,
71
(
2010
).
3.
G.-X.
Miao
,
M.
Müller
 et al.,
Phys. Rev. Lett.
102
,
076601
(
2009
).
4.
A.
Mauger
and
C.
Godart
,
Phys. Rep.
141
,
51
(
1986
).
5.
K. J.
Hubbard
 et al.,
J. Mater. Res.
11
,
2757
(
1996
).
6.
G.-X.
Miao
 et al.,
Rep. Prog. Phys.
74
,
036501
(
2011
).
7.
M.
Müller
 et al.,
Europhys. Lett.
88
,
47006
(
2009
).
8.
C.
Caspers
,
M.
Müller
 et al.,
Phys. Rev. B
84
,
205217
(
2011
);
C.
Caspers
,
M.
Müller
,
Phys. Status Solidi (RRL)
5
,
441
(
2011
).
9.
P. G.
Steeneken
 et al.,
Phys. Rev. Lett.
88
,
047201
(
2002
).
10.
R.
Sutarto
 et al.,
Phys. Rev. B
79
,
203518
(
2009
).
11.
A.
Schmehl
 et al.,
Nature Mater.
6
,
882
(
2007
).
12.
A. G.
Swartz
 et al.,
Appl. Phys. Lett.
97
,
112509
(
2010
);
A. G.
Swartz
,
J. Appl. Phys.
111
,
083912
(
2012
).
13.
A.
Gloskovskii
 et al.,
J. Electron Spectrosc. Relat. Phenom.
185
,
47
(
2012
).
14.
M.
Gorgoi
 et al.,
Nucl. Instrum. Methods Phys. Res. A
601
,
48
(
2009
).
15.
S.
Tanuma
 et al.,
Surf. Interface Anal.
43
,
689
(
2011
).
16.
Th.
Eickhoff
 et al.,
J. Electron Spectrosc. Relat. Phenom.
137–140
,
85
(
2004
).
17.
K.
Hirose
 et al.,
J. Phys. IV France
132
,
83
(
2006
).
18.
J. E.
Northrup
,
Phys. Rev. B
44
,
1419
(
1991
).
19.
The native europium silicide (EuSi2) favors a paramagnetic metallic phase, as calculated by its heat of formation. M. Ležaić, private communication (
2011
).
20.
E.-J.
Cho
and
S.-J.
Oh
,
Phys. Rev. B
51
,
10146
(
1995
);
E.-J.
Cho
and
S.-J.
Oh
,
Phys. Rev. B
59
,
R15613
(
1999
).
21.
B. A.
Orlowski
 et al.,
J. Electron. Spectrosc. Relat. Phenom.
137–140
,
763
(
2004
).
22.
R.
Vercaemst
 et al.,
J. Electron Spectrosc. Relat. Phenom.
74
,
45
(
1995
).
You do not currently have access to this content.