Tungsten oxide–silicon dioxide (WOx–SiOy) composite thin films were deposited for the first time via the remote oxygen plasma-enhanced atomic layer deposition (ALD) process using a novel metal-organic heteronuclear and heteroleptic precursor, bis(tert-butylimido)bis(trimethylsilylmethyl)tungsten. Self-limiting ALD growth was demonstrated over a wide temperature window of 203–328 °C with growth per cycle decreasing with increasing temperature from 0.75 to 0.4 Å/cycle, respectively. Residual gas analysis revealed ligand competition and showed that ligand reaction during ALD nucleation and growth was a function of deposition temperature, thereby affecting the film composition. As the temperature increased from 203 to 328 °C, the film composition [W/(Si + W)] ranged from 0.45 to 0.53. In addition, the carbon impurity content was reduced and the refractive index increased from 1.73 to 1.96, the density increased from 4.63 to 5.6 g/cm3, and the optical bandgap decreased from 3.45 to 3.27 eV. Grazing angle x-ray diffraction indicated that as-deposited films were amorphous. Upon annealing in O2 at 500 °C or higher, depending on deposition temperature, films are crystalized into the triclinic WO3 phase. At the same time, WO3 is sublimed from the surface and films are reduced in thickness.

1.
C. J.
Howard
,
V.
Luca
, and
K. S.
Knight
,
J. Phys.: Condens. Matter
14
,
377
(
2002
).
2.
Y.
Bouhoute
 et al,
ACS Catal.
6
,
1
(
2016
).
3.
B.
Baloukas
and
L.
Martinu
,
Appl. Opt.
51
,
3346
(
2012
).
4.
X.
Wang
,
G.
Sakai
,
K.
Shimanoe
,
N.
Miura
, and
N.
Yamazoe
,
Sens. Actuators, B
45
,
141
(
1997
).
5.
G.
Gao
,
S.
Xue
,
H.
Wang
,
Z.
Zhang
,
G.
Wu
,
T. T.
Debela
, and
H. S.
Kang
,
ACS Sustainable Chem. Eng.
9
,
17319
(
2021
).
6.
D.
Saygin-Hinczewski
,
M.
Hinczewski
,
I.
Sorar
,
F. Z.
Tepehan
, and
G. G.
Tepehan
,
Sol. Energy Mater. Sol. Cells
92
,
821
(
2008
).
7.
E. I.
Ross-Medgaarden
and
I. E.
Wachs
,
J. Phys. Chem. C
111
,
15089
(
2007
).
8.
S.
Maksasithorn
,
P.
Praserthdam
,
K.
Suriye
, and
D. P.
Debecker
,
Microporous Mesoporous Mater.
213
,
125
(
2015
).
9.
A. J. M.
Mackus
,
J. R.
Schneider
,
C.
MacIsaac
,
J. G.
Baker
, and
S. F.
Bent
,
Chem. Mater.
31
,
1142
(
2019
).
10.
V. Yu
Vasilyev
,
ECS J. Solid State Sci.
10
,
053004
(
2021
).
11.
C. E.
Tracy
and
D. K.
Benson
,
J. Vac. Sci. Technol. A
4
,
2377
(
1986
).
12.
W. W.
Lee
and
R. R.
Reeves
,
MRS Proc.
250
,
137
(
1991
).
13.
P.
Tägtström
,
P.
Maårtensson
,
U.
Jansson
, and
J.-O.
Carlsson
,
J. Electrochem. Soc.
146
,
3139
(
1999
).
14.
A.
Strobel
,
H.-D.
Schnabel
,
U.
Reinhold
,
S.
Rauer
, and
A.
Neidhardt
,
J. Vac. Sci. Technol. A
34
,
01A118
(
2016
).
15.
K.
Bergum
,
A.
Magrasó
,
H.
Fjellvåg
, and
O.
Nilsen
,
J. Mater. Chem. A
2
,
18463
(
2014
).
16.
Z.
Feng
,
C.-Y.
Kim
,
J. W.
Elam
,
Q.
Ma
,
Z.
Zhang
, and
M. J.
Bedzyk
,
J. Am. Chem. Soc.
131
,
18200
(
2009
).
17.
J.
Malm
,
T.
Sajavaara
, and
M.
Karppinen
,
Chem. Vap. Deposition
18
,
245
(
2012
).
18.
D. K.
Nandi
and
S. K.
Sarkar
,
Energy Procedia
54
,
782
(
2014
).
19.
D. H. K.
Jackson
,
B. A.
Dunn
,
Y.
Guan
, and
T. F.
Kuech
,
AIChE J.
60
,
1278
(
2014
).
20.
K.
Zhang
,
C.
McCleese
,
P.
Lin
,
X.
Chen
,
M.
Morales
,
W.
Cao
,
F. J.
Seo
,
C.
Burda
, and
H.
Baumgart
,
ECS Trans.
69
,
199
(
2015
).
21.
C. L.
Dezelah
,
O. M.
El-Kadri
,
I. M.
Szilágyi
,
J. M.
Campbell
,
K.
Arstila
,
L.
Niinistö
, and
C. H.
Winter
,
J. Am. Chem. Soc.
128
,
9638
(
2006
).
22.
J.-G.
Song
 et al,
ACS Nano
7
,
11333
(
2013
).
23.
R.
Liu
,
Y.
Lin
,
L.-Y.
Chou
,
S. W.
Sheehan
,
W.
He
,
F.
Zhang
,
H. J. M.
Hou
, and
D.
Wang
,
Angew. Chem., Int. Ed.
50
,
499
(
2011
).
24.
S.
Zhuiykov
,
L.
Hyde
,
Z.
Hai
,
M. K.
Akbari
,
E.
Kats
,
C.
Detavernier
,
C.
Xue
, and
H.
Xu
,
Appl. Mater. Today
6
,
44
(
2017
).
25.
Z.
Hai
,
M. K.
Akbari
,
C.
Xue
,
H.
Xu
,
L.
Hyde
, and
S.
Zhuiykov
,
Appl. Surf. Sci.
405
,
169
(
2017
).
26.
See supplementary material at https://www.scitation.org/doi/suppl/10.1116/6.0002214 for (1) DSC data of BTBAW, (2) comparison of TWALL and TDEP, (3) XRR model fits for as-dep films and comparison WOx–SiOy thickness extracted using XRR versus SE, (4) study of nucleation and film growth versus ALD cycles and TDEP on TiN and TaN, (5) Scherrer crystallite size for films as-deposited and annealed, (6) XRR model fits and extracted parameters for WOx–SiOy films postannealing, (7) Residual gas analysis of reaction by-products with shorter BITSW pulse length, (8) film growth uniformity using BITSW/H2O, and (9) XPS spectra of N1s and C1s core levels pre and post O2 annealing.
27.
N.
Li
,
L. P.
Feng
,
J.
Su
,
W.
Zeng
, and
Z. T.
Liu
,
RSC Adv.
6
,
64879
(
2016
).
28.
S.
Balasubramanyam
,
A.
Sharma
,
V.
Vandalon
,
H. C. M.
Knoops
,
W. M. M.
(Erwin) Kessels
, and
A. A.
Bol
,
J. Vac. Sci. Technol. A
36
,
01B103
(
2018
).
29.
C. T.
Chen
 et al,
Sci. Rep.
9
,
2768
(
2019
).
30.
U.
Kilic
,
A.
Mock
,
D.
Sekora
,
S.
Gilbert
,
S.
Valloppilly
,
N.
Ianno
,
M.
Langell
,
E.
Schubert
, and
M.
Schubert
,
Sci. Rep.
10
,
10392
(
2020
).
31.
Y.
Zhao
,
S.
Balasubramanyam
,
R.
Sinha
,
R.
Lavrijsen
,
M. A.
Verheijen
,
A. A.
Bol
, and
A.
Bieberle-Hütter
,
ACS Appl. Energy Mater.
1
,
5887
(
2018
).
32.
D. B.
Farmer
,
M.
Copel
,
T.
Todorov
,
J. A.
Ott
,
M.
Hopstaken
,
H.
Bui
,
C.
Tabachnick
,
G.
Fraczak
, and
G.
Totir
,
Chem. Mater.
33
,
2267
(
2021
).
33.
A. R.
Mouat
,
A. U.
Mane
,
J. W.
Elam
,
M.
Delferro
,
T. J.
Marks
, and
P. C.
Stair
,
Chem. Mater.
28
,
1907
(
2016
).
34.
M.
Mattinen
 et al,
Chem. Mater.
30
,
8690
(
2018
).
35.
R. I.
Romanov
,
M. G.
Kozodaev
,
Y. Y.
Lebedinskii
,
T. V.
Perevalov
,
A. S.
Slavich
,
C. S.
Hwang
, and
A. M.
Markeev
,
J. Phys. Chem. C
124
,
18156
(
2020
).
36.
M. G.
Kozodaev
,
R. I.
Romanov
,
A. G.
Chernikova
, and
A. M.
Markeev
,
J. Phys. Chem. C
125
,
21663
(
2021
).
37.
R. A.
May
,
L.
Kondrachova
,
B. P.
Hahn
, and
K. J.
Stevenson
,
J. Phys. Chem. C
111
,
18251
(
2007
).
38.
S.
Sawada
and
G. C.
Danielson
,
Phys. Rev.
113
,
1008
(
1959
).
39.
R.
Diehl
,
G.
Brandt
, and
E.
Salje
,
Acta Crystallogr., Sect. B
34
,
1105
(
1978
).
40.
W.
Gerhartz
,
Ullmann's Encyclopedia of Industrial Chemistry
, 5th ed. (
VCH
,
Deerfield Beach
,
1985
).
41.
J. I.
Pankove
and
D. A.
Kiewit
,
J. Electrochem. Soc.
119
,
156C
(
1972
).
42.
S. K.
Gullapalli
,
R. S.
Vemuri
, and
C. V.
Ramana
,
Appl. Phys. Lett.
96
,
171903
(
2010
).
43.
S. K.
Deb
,
Philos. Mag.
27
,
801
(
1973
).
44.
F. P.
Koffyberg
,
K.
Dwight
, and
A.
Wold
,
Solid State Commun.
30
,
433
(
1979
).
45.
Z. A.
Weinberg
,
G. W.
Rubloff
, and
E.
Bassous
,
Phys. Rev. B
19
,
3107
(
1979
).
46.
H.
Zheng
,
J. Z.
Ou
,
M. S.
Strano
,
R. B.
Kaner
,
A.
Mitchell
, and
K.
Kalantar-zadeh
,
Adv. Funct. Mater.
21
,
2175
(
2011
).
47.
D.
Gogova
,
K.
Gesheva
,
A.
Szekeres
, and
M.
Sendova-Vassileva
,
Phys. Status Solidi A
176
,
969
(
1999
).
48.
C. G.
Granqvist
,
Handbook of Inorganic Electrochromic Materials
(
Elsevier
,
Amsterdam
,
1995
).
49.
R.
Alfonsetti
,
G.
De Simone
,
L.
Lozzi
,
M.
Passacantando
,
P.
Picozzi
, and
S.
Santucci
,
Surf. Interface Anal.
22
,
89
(
1994
).
50.
A. G.
Shard
,
Surf. Interface Anal.
46
,
175
(
2014
).
51.
M.
Gillet
,
R.
Delamare
, and
E.
Gillet
,
J. Cryst. Growth
279
,
93
(
2005
).
52.
G.
Meyer
,
J. F.
Oosterom
, and
W. J.
van Oeveren
,
Recl. Trav. Chim. Pays-Bas
78
,
417
(
1959
).
53.
T.
Boublik
,
V.
Fried
, and
E.
Hala
. in
The Vapour Pressures of Pure Substances
, 2nd rev. ed. (
Elsevier
,
Amsterdam
,
1984
).
54.
J.
Tupala
,
M.
Kemell
,
M.
Mattinen
,
K.
Meinander
,
S.
Seppälä
,
T.
Hatanpää
,
J.
Räisänen
,
M.
Ritala
, and
M.
Leskelä
,
J. Vac. Sci. Technol. A
35
,
041506
(
2017
).
55.
S.
Haukka
and
A.
Root
,
J. Phys. Chem.
98
,
1695
(
1994
).
56.
J. S.
Becker
,
S.
Suh
,
S.
Wang
, and
R. G.
Gordon
,
Chem. Mater.
15
,
2969
(
2003
).
57.
J.
Hämäläinen
,
F.
Munnik
,
T.
Hatanpää
,
J.
Holopainen
,
M.
Ritala
, and
M.
Leskelä
,
J. Vac. Sci. Technol. A
30
,
01A106
(
2012
).
58.
T. E.
Hong
 et al,
J. Phys. Chem. C
119
,
1548
(
2015
).

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