There has been much interest in developing scandium doped aluminum nitride (ScAlN) thin films for use in electronic devices, due to their excellent piezoMEMS response, large spontaneous polarization, and the capability for CMOS-compatible integration. As with the undoped AlN film, the formation of an oxide overlayer on the air-exposed ScAlN film can modulate its surface structure and the electrical properties. In this study, we investigate the effects of surface oxidation on a ScAlN film by characterizing the film microstructure and the elemental chemical states. We found that amorphous phase and small crystallites co-exist in the oxide overlayer, which is remarkably different from the columnar (0002) crystalline texture in the bulk ScAlN film. X-ray photoelectron spectroscopy core-level analyses confirm the formation of Al–O and Sc–O bonds. Moreover, the valence band maximum of the oxide overlayer shifts toward a higher binding energy, indicating a high energy barrier at the ScAlN/metal interface. Our results suggest that ScAlN surface oxidation is a chemical reaction-driven and self-limited process.

1.
S.
Zhao
,
Z.
Luo
, and
T.
Wu
,
IEEE Electron Device Lett.
42
,
1378
(
2021
).
2.
D. K. T.
Ng
,
C. P.
Ho
,
L.
Xu
,
W.
Chen
,
Y. H.
Fu
,
T.
Zhang
,
L. Y.
Siow
,
N.
Jaafar
,
E. J.
Ng
,
Y.
Gao
,
H.
Cai
,
Q.
Zhang
, and
L. Y. T.
Lee
,
Sens. Actuators, B
346
,
130437
(
2021
).
3.
N.
Wang
,
Y.
Zhu
,
G. L.
Chua
,
B.
Chen
,
S.
Merugu
,
N.
Singh
, and
Y.
Gu
,
IEEE Electron Device Lett.
40
,
957
(
2019
).
4.
M.
Akiyama
,
T.
Kamohara
,
K.
Kano
,
A.
Teshigahara
,
Y.
Takeuchi
, and
N.
Kawahara
,
Adv. Mater.
21
,
593
(
2009
).
5.
K.
Frei
,
R.
Trejo-Hernandez
,
S.
Schutt
,
L.
Kriste
,
M.
Prescher
,
R.
Aidam
,
S.
Muller
,
P.
Waltereit
,
O.
Ambacher
, and
M.
Fiederle
,
Jpn. J. Appl. Phys.
58
,
SC1045
(
2019
).
6.
C. S.
Sandu
,
F.
Parsapour
,
D.
Xiao
,
R.
Nigon
,
L. M.
Riemer
,
T.
LaGrange
, and
P.
Muralt
,
Thin Solid Films
697
,
137819
(
2020
).
7.
C.
Liu
,
Q.
Wang
,
Y. W.
Yang
,
T.
Cao
,
L.
Chen
,
M.
Li
,
F.
Liu
,
D. K.
Loke
,
J.
Kang
, and
Y.
Zhu
, in
2021 IEEE International Electron Device Meeting (IEDM)
, San Francisco, December 11–16 (
IEEE
,
2021
), p.
8.1.1
.
8.
M.
Akiyama
,
T.
Kamohara
,
K.
Kano
,
A.
Teshigahara
, and
N.
Kawahara
,
Appl. Phys. Lett.
93
,
021903
(
2008
).
9.
M.
Li
,
B.
Chen
,
J.
Xie
,
W.
Song
, and
Y.
Zhu
, in
2020 IEEE International Ultrasonics Symposium (IUS)
, September 7–11 (
IEEE
,
2020
).
10.
M.
Gillinger
,
M.
Schneider
,
A.
Bittner
,
P.
Nicolay
, and
U.
Schmid
,
J. Appl. Phys.
117
,
065303
(
2015
).
11.
E.
Osterlund
,
G.
Ross
,
M. A.
Caro
,
M.
Paulasto-Krockel
,
A.
Hollmann
,
M.
Klaus
,
M.
Meixner
,
C.
Genzel
,
P.
Koppinen
,
T.
Pensala
,
A.
Zukauskaite
, and
M.
Trebala
,
Phys. Rev. Mater.
5
,
035001
(
2021
).
12.
S.
Song
and
F.
Placido
,
Appl. Phys. Lett.
99
,
121901
(
2011
).
13.
A.
Bellucci
,
S.
Orlando
,
M.
Girolami
,
M.
Mastellone
,
V.
Serpente
,
B.
Paci
,
A.
Generosi
,
A.
Mezzi
,
S.
Kaciulis
,
R.
Polini
, and
D. M.
Trucchi
,
AIP Conf. Proc.
2416
,
020004
(
2021
).
14.
N.
Gungor
and
M.
Alevli
,
J. Vac. Sci. Technol. A
40
,
022404
(
2022
).
15.
R. C.
Farrell
,
V. R.
Pagan
,
A.
Kabulski
,
S.
Kuchibhatla
,
J.
Harman
,
K. R.
Kasarla
,
L. E.
Rodak
,
P.
Famouri
,
J. P.
Hensel
, and
D.
Korakakis
,
MRS Online Proc. Library
1052
,
618
(
2008
).
16.
T.
Aubert
,
J.
Bardong
,
O.
Legrani
,
O.
Elmazria
,
M. B.
Assouar
,
G.
Bruckner
, and
A.
Talbi
,
J. Appl. Phys.
114
,
014505
(
2013
).
17.
C.-T.
Yeh
and
W.-H.
Tuan
,
J. Adv. Ceram.
6
,
27
(
2017
).
18.
X.
Hou
,
K.-C.
Chou
,
X.
Zhong
, and
S.
Seetharaman
,
J. Alloys Compd.
465
,
90
(
2008
).
19.
J.
Chaudhuri
,
L.
Nyakiti
,
R. G.
Lee
,
Z.
Gu
,
J. H.
Edgar
, and
J. G.
Wenm
,
Mater. Charact.
58
,
672
(
2007
).
20.
Z.
Fang
,
E.
Wang
,
Y.
Chen
,
X.
Hou
,
K.-C.
Chou
,
W.
Yang
,
J.
Chen
, and
M.
Shang
,
ACS Appl. Mater. Interfaces
10
,
30811
(
2018
).
21.
P.
Musavigharavi
,
A. C.
Meng
,
D.
Wang
,
J.
Zheng
,
A. C.
Foucher
,
R. H.
Olsson
 III
, and
E. A.
Stach
,
J. Phys. Chem. C
125
,
14394
(
2021
).
22.
X.
Liu
,
J.
Zheng
,
D.
Wang
,
P.
Musavigharavi
,
E. A.
Stach
,
R.
Olsson
 III
, and
D.
Jariwala
,
Appl. Phys. Lett.
118
,
202901
(
2021
).
23.
D.
Wang
,
J.
Zheng
,
P.
Musavigharavi
,
W.
Zhu
,
A. C.
Foucher
,
S. E.
Trolier-McKinsky
,
E. A.
Stach
, and
R. H.
Olsson
 III
,
IEEE Electron Device Lett.
41
,
1774
(
2020
).
24.
Y.
Matsui
,
M.
Hiratani
,
Y.
Nakamura
,
I.
Asano
, and
F.
Yano
,
J. Vac. Sci. Technol. A
20
,
605
(
2002
).
25.
Y. R.
Luo
,
Comprehensive Handbook of Chemical Bond Energies
(
CRC Press
,
Boca Raton, FL
,
2007
).
26.
O.
Sharia
,
K.
Tse
,
J.
Robertson
, and
A. A.
Demkov
,
Phys. Rev. B
79
,
125305
(
2009
).
27.
J.
Robertson
and
Z.
Zhang
,
MRS Bull.
46
,
1
(
2021
).
28.
D. B.
Williams
and
C. B.
Carter
, “
Quantitative x-ray analysis
,” in
Transmission Electron Microscopy
(
Springer
,
1994
), Vol.
43
, pp.
639
662
.
29.
N.
Rowlands
,
E. F.
Schumacher
, and
A. W.
Nicholls
,
Microsc. Microanal.
19
,
1074
(
2013
).
30.
X.
Zhang
,
P.
Zeng
,
Y.
Ma
,
Y.
Jiang
, and
A. H.
Li
,
Mater. Des.
217
,
110605
(
2022
).
31.
D. M.
Detert
,
K. B.
Tom
,
C.
Battaglia
,
J. D.
Denlinger
,
S. H. N.
Lim
,
A.
Javey
,
A.
Anders
,
O. D.
Dubon
,
K. M.
Yu
, and
W.
Walukiewicz
,
J. Appl. Phys.
115
,
233708
(
2014
).
32.
A. M.
Shing
,
Y.
Tolstova
,
N. S.
Lewis
, and
H. A.
Atwater
,
Appl. Phys. A
123
,
735
(
2017
).
33.
V. A.
Gritsenko
,
A. V.
Shaposhnikov
,
W. M.
Kwok
,
H.
Wong
, and
G. M.
Jidomirov
,
Thin Solid Films
437
,
135
(
2003
).

Supplementary Material

You do not currently have access to this content.