Ab initio molecular dynamics liquid-quench simulations and hybrid density functional calculations are performed to model the effects of room-temperature atomic fluctuations and photo-illumination on the structural and electronic properties of amorphous sub-stoichiometric In2O2.96. A large configurational ensemble is employed to reliably predict the distribution of localized defects as well as their response to the thermal and light activation. The results reveal that the illumination effects on the carrier concentration are greater in amorphous configurations with shorter In–O bond length and reduced polyhedral sharing as compared to the structures with a more uniform morphology. The obtained correlation between the photo-induced carrier density and the reduction in the number of fully coordinated In-atoms implies that metal oxides with a significant fraction of crystalline/amorphous interfaces would show a more pronounced response to illumination. Photo-excitation also produces In–O2–In defects that have not been previously found in sub-stoichiometric amorphous oxides; these defects are responsible for carrier instabilities due to overdoping.
References
1.
C.
Kilic
and A.
Zunger
, “Origins of coexistence of conductivity and transparency in SnO2
,” Phys. Rev. Lett.
88
, 95501
(2002
).2.
C. G. V.
de Walle
, “Strategies for controlling the conductivity of wide-band-gap semiconductors
,” Phys. Stat. Solidi B
229
, 221
–228
(2002
).3.
S.
Lany
and A.
Zunger
, “Dopability, intrinsic conductivity and nonstoichiometry of transparent conducting oxides
,” Phys. Rev. Lett.
98
, 045501
(2007
).4.
A.
Murat
, A. U.
Adler
, T. O.
Mason
, and J. E.
Medvedeva
, “Carrier generation in multicomponent wide-bandgap oxides: InGaZnO4
,” J. Am. Chem. Soc.
135
, 5685
–5692
(2013
).5.
F.
Gunkel
, D. V.
Christensen
, Y. Z.
Chen
, and N.
Pryds
, “Oxygen vacancies: The (in)visible friend of oxide electronics
,” Appl. Phys. Lett.
116
, 120505
(2020
).6.
K.
Ide
, K.
Nomura
, H.
Hosono
, and T.
Kamiya
, “Electronic defects in amorphous oxide semiconductors: A review
,” Phys. Status Solidi A
216
, 1800372
(2019
).7.
J. E.
Medvedeva
, D. B.
Buchholz
, and R. P.
Chang
, “Recent advances in understanding the structure and properties of amorphous oxide semiconductors
,” Adv. Electron. Mater.
3
, 1700082
(2017
).8.
J.
Medvedeva
, I.
Zhuravlev
, C.
Burris
, D.
Buchholz
, M.
Grayson
, and R.
Chang
, “Origin of high carrier concentration in amorphous wide-bandgap oxides: Role of disorder in defect formation and electron localization in In2
,” J. Appl. Phys.
127
, 175701
(2020
).9.
J.
Medvedeva
, in Amorphous Oxide Semiconductors: IGZO and Related Materials for Display and Memory
, Edited by H.
Hosono
and H.
Kumomi
(Wiley
, 2022
).10.
J. E.
Medvedeva
and B.
Bhattarai
, “Hydrogen doping in wide-bandgap amorphous In–Ga–O semiconductors
,” J. Mater. Chem. C
8
, 15436
–15449
(2020
).11.
J. E.
Medvedeva
, E.
Caputa-Hatley
, and I.
Zhuravlev
, “Metallic networks and hydrogen compensation in highly nonstoichiometric amorphous
,” Phys. Rev. Mater.
6
, 025601
(2022
).12.
D. B.
Buchholz
, Q.
Ma
, D.
Alducin
, A.
Ponce
, M.
Jose-Yacaman
, R.
Khanal
, J. E.
Medvedeva
, and R. P.
Chang
, “The structure and properties of amorphous indium oxide
,” Chem. Mater.
26
, 5401
–5411
(2014
).13.
T.-C.
Fung
, C.-S.
Chuang
, K.
Nomura
, H-P. D.
Shieh
, H.
Hosono
, and J.
Kanicki
, “Photofield-effect in amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors
,” J. Inf. Disp.
9
, 21
–29
(2008
).14.
P.
Migliorato
, M.
Delwar Hossain Chowdhury
, J.
Gwang Um
, M.
Seok
, and J.
Jang
, “Light/negative bias stress instabilities in indium gallium zinc oxide thin film transistors explained by creation of a double donor
,” Appl. Phys. Lett.
101
, 123502
(2012
).15.
J. K.
Jeong
, “Photo-bias instability of metal oxide thin film transistors for advanced active matrix displays
,” J. Mater. Res.
28
, 2071
–2084
(2013
).16.
C.-H.
Han
, S.-S.
Kim
, K.-R.
Kim
, D.-H.
Baek
, S.-S.
Kim
, and B-. D.
Choi
, “Effects of electron trapping and interface state generation on bias stress induced in indium-gallium-zinc oxide thin-film transistors
,” Jpn. J. Appl. Phys.
53
, 08NG04
(2014
).17.
A. J.
Flewitt
and M. J.
Powell
, “A thermalization energy analysis of the threshold voltage shift in amorphous indium gallium zinc oxide thin film transistors under simultaneous negative gate bias and illumination
,” J. Appl. Phys.
115
, 134501
(2014
).18.
J.
Luo
, “Characterizing and modeling transient photo-conductivity in amorphous In-Ga-Zn-O thin films
,” Ph.D. thesis (Northwestern University
, 2016
).19.
T.
Kamiya
, K.
Nomura
, and H.
Hosono
, “Origins of high mobility and low operation voltage of amorphous oxide TFTs: Electronic structure, electron transport, defects and doping
,” J. Disp. Technol.
5
, 273
–288
(2009
).20.
G.
Kresse
and J.
Hafner
, “Ab initio molecular dynamics for liquid metals
,” Phys. Rev. B
47
, 558
–561
(1993
).21.
G.
Kresse
and J.
Hafner
, “Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium
,” Phys. Rev. B
49
, 14251
–14269
(1994
).22.
G.
Kresse
and J.
Furthmuller
, “Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set
,” Phys. Rev. B
54
, 11169
–11186
(1996
).23.
G.
Kresse
and J.
Furthmuller
, “Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set
,” Comput. Mater. Sci.
6
, 15
–50
(1996
).24.
P.
Hohenberg
and W.
Kohn
, “Inhomogeneous electron gas
,” Phys. Rev.
136
, B864
–B871
(1964
).25.
W.
Kohn
and L. J.
Sham
, “Self-consistent equations including exchange and correlation effects
,” Phys. Rev.
140
, A1133
–A1138
(1965
).26.
J. P.
Perdew
, K.
Burke
, and M.
Ernzerhof
, “Generalized gradient approximation made simple
,” Phys. Rev. Lett.
77
, 3865
–3868
(1996
).27.
J. P.
Perdew
, K.
Burke
, and M.
Ernzerhof
, “Generalized gradient approximation made simple [Phys. Rev. Lett. 77, 3865 (1996)]
,” Phys. Rev. Lett.
78
, 1396
–1396
(1997
).28.
P. E.
Blochl
, “Projector augmented-wave method
,” Phys. Rev. B
50
, 17953
–17979
(1994
).29.
G.
Kresse
and D.
Joubert
, “From ultrasoft pseudopotentials to the projector augmented-wave method
,” Phys. Rev. B
59
, 1758
–1775
(1999
).30.
J.
Heyd
, G. E.
Scuseria
, and M.
Ernzerhof
, “Hybrid functionals based on a screened Coulomb potential
,” J. Chem. Phys.
118
, 8207
–8215
(2003
).31.
J.
Heyd
, J. E.
Peralta
, G. E.
Scuseria
, and R. L.
Martin
, “Energy band gaps and lattice parameters evaluated with the Heyd-Scuseria-Ernzerhof screened hybrid functional
,” J. Chem. Phys.
123
, 174101
(2005
).32.
H.
Hosono
, H.
Kawazoe
, and N.
Matsunami
, “Experimental evidence for Frenkel defect formation in amorphous by electronic excitation
,” Phys. Rev. Lett.
80
, 317
–320
(1998
).33.
A.
Shluger
and E.
Stefanovich
, “Models of the self-trapped exciton and nearest-neighbor defect pair in SiO2
,” Phys. Rev. B
42
, 9664
(1990
).34.
J. E.
Medvedeva
, K.
Sharma
, B.
Bhattarai
, and M. I.
Bertoni
, “Hydrogen behavior at crystalline/amorphous interface of transparent oxide semiconductor and its effects on carrier transport and crystallization
,” ACS Appl. Mater. Interfaces
14
, 39535
–39547
(2022
).© 2022 Author(s). Published under an exclusive license by AIP Publishing.
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