Hydrogen exposure and annealing at 400 °C leads to a layer-by-layer etching of the n-doped GaAs(110) cleavage surface removing islands and forming preferentially step edge sections with [001] normal vector. In addition, a large density of negatively charged point defects is formed, leading to a Fermi level pinning in the lower part of the bandgap. Their charge transfer level is in line with that of Ga vacancies only, suggesting that adatoms desorb preferentially due to hydrogen bonding and subsequent Ga–H desorption. The results obtained on cleavage surfaces imply that the morphology of nanowire sidewall facets obtained by hydrogen cleaning is that of an etched surface, but not of the initial growth surface. Likewise, the hydrogen-cleaned etched surface does not reveal the intrinsic electronic properties of the initially grown nanowires.
REFERENCES
1.
H. J.
Joyce
, Q.
Gao
, H. H.
Tan
, C.
Jagadish
, Y.
Kim
, X.
Zhang
, Y.
Guo
, and J.
Zou
, Nano Lett.
7
, 921
(2007
). 2.
B. A.
Wacaser
, K.
Deppert
, L. S.
Karlsson
, L.
Samuelson
, and W.
Seifert
, J. Cryst. Growth
287
, 504
(2006
). 3.
B.
Mayer
et al., Nat. Commun.
4
, 2931
(2013
). 4.
S.
Breuer
, C.
Pfuller
, T.
Flissikowski
, O.
Brandt
, H. T.
Grahn
, L.
Geelhaar
, and H.
Riechert
, Nano Lett.
11
, 1276
(2011
). 5.
G.
Mariani
, A. C.
Scofield
, C.-H.
Hung
, and D. L.
Huffaker
, Nat. Commun.
4
, 1497
(2013
). 6.
L. C.
Chuang
, F. G.
Sedgwick
, R.
Chen
, W. S.
Ko
, M.
Moewe
, K. W.
Ng
, T.-T. D.
Tran
, and C.
Chang-Hasnain
, Nano Lett.
11
, 385
(2011
). 7.
E.
Hilner
, U.
Håkanson
, L. E.
Fröberg
, M.
Karlsson
, P.
Kratzer
, E.
Lundgren
, L.
Samuelson
, and A.
Mikkelsen
, Nano Lett.
8
, 3978
(2008
). 8.
T.
Xu
, J. P.
Nys
, A.
Addad
, O. I.
Lebedev
, A.
Urbieta
, B.
Salhi
, M.
Berthe
, B.
Grandidier
, and D.
Stiévenard
, Phys. Rev. B
81
, 115403
(2010
). 9.
T.
Xu
et al., Nanotechnology
23
, 095702
(2012
). 10.
P.
Capiod
et al., Appl. Phys. Lett.
103
, 122104
(2013
). 11.
M.
Hjort
, S.
Lehmann
, J.
Knutsson
, R.
Timm
, D.
Jacobsson
, E.
Lundgren
, K.
Dick
, and A.
Mikkelsen
, Nano Lett.
13
, 4492
(2013
). 12.
M.
Hjort
et al., ACS Nano
8
, 12346
(2014
). 13.
A. D.
Álvarez
et al., Nano Lett.
15
, 6440
(2015
). 14.
J. L.
Webb
, J.
Knutsson
, M.
Hjort
, S.
Gorji Ghalamestani
, K. A.
Dick
, R.
Timm
, and A.
Mikkelsen
, Nano Lett.
15
, 4865
(2015
). 15.
T.
Xu
et al., Appl. Phys. Lett.
107
, 112102
(2015
). 16.
J. V.
Knutsson
, S.
Lehmann
, M.
Hjort
, P.
Reinke
, E.
Lundgren
, K. A.
Dick
, R.
Timm
, and A.
Mikkelsen
, ACS Appl. Mat. Interfaces
7
, 5748
(2015
). 17.
M.
Schnedler
et al., Phys. Rev. B
94
, 195306
(2016
). 18.
M.
Hjort
, P.
Kratzer
, S.
Lehmann
, S. J.
Patel
, K. A.
Dick
, C. J.
Palmstrøm
, R.
Timm
, and A.
Mikkelsen
, Nano Lett.
17
, 3634
(2017
). 19.
A. D.
Álvarez
et al., Nanotechnology
30
, 324002
(2019
). 20.
M.
Schnedler
et al., Nano Lett.
19
, 8801
(2019
). 21.
F. M.
Ross
, Rep. Prog. Phys.
73
, 114501
(2010
). 22.
P.
Quadbeck
, Ph.
Ebert
, K.
Urban
, J.
Gebauer
, and R.
Krause-Rehberg
, Appl. Phys. Lett.
76
, 300
(2000
). 23.
R. M.
Feenstra
, J. A.
Stroscio
, J.
Tersoff
, and A. P.
Fein
, Phys. Rev. Lett.
58
, 1192
(1987
). 24.
M. A.
Rosentreter
, M.
Wenderoth
, N. H.
Theuerkrauf
, A. J.
Heinrich
, M. A.
Schneider
, and R. G.
Ulbrich
, Phys. Rev. B
56
, 10538
(1997
). 25.
K.
Sauthoff
, M.
Wenderoth
, A. J.
Heinrich
, M. A.
Rosentreter
, K. J.
Engel
, T. C. G.
Reusch
, and R. G.
Ulbrich
, Phys. Rev. B
60
, 4789
(1999
). 26.
G.
Lengel
, R.
Wilkins
, G.
Brown
, M.
Weimer
, J.
Gryko
, and R. E.
Allen
, Phys. Rev. Lett.
72
, 836
(1994
). 27.
Ph.
Ebert
, K.
Urban
, and M. G.
Lagally
, Phys. Rev. Lett.
72
, 840
(1994
). 28.
G.
Schwarz
, “Untersuchungen zu Defekten auf und nahe der (110)-Oberfläche von GaAs und weiteren III-V-Halbleitern,” Ph.D. thesis (Technische Universität Berlin, Berlin, 2002).29.
Ph.
Ebert
, Surf. Sci. Reports
33
, 121
(1999
). 30.
L. J.
Whitman
, J. A.
Stroscio
, R. A.
Dragoset
, and R. J.
Celotta
, Phys. Rev. B
42
, 7288
(1990
). 31.
G.
Cox
, K.
Graf
, D.
Szynka
, U.
Poppe
, and K.
Urban
, Vacuum
41
, 591
(1990
). 32.
C.
Domke
, Ph.
Ebert
, M.
Heinrich
, and K.
Urban
, Phys. Rev. B
54
, 10288
(1996
). 33.
S.
Landrock
, “Investigation of nanoscale potential fluctuations and defects in 2D semiconducting structures by scanning tunneling microscopy,” Ph.D. thesis (RWTH Aachen, Juel-4290, Forschungszentrum Jülich, 2009).34.
S.
Gaan
, R. M.
Feenstra
, Ph.
Ebert
, R. E.
Dunin-Borkowski
, J.
Walker
, and E.
Towe
, Surf. Sci.
606
, 28
(2012
). 35.
J. A.
Stroscio
, R. M.
Feenstra
, and A. P.
Fein
, Phys. Rev. Lett.
58
, 1668
(1987
). 36.
R. J.
Hamers
, J. Vac. Sci. Technol. B
6
, 1462
(1988
). 37.
G.
Lengel
, R.
Wilkins
, G.
Brown
, and M.
Weimer
, J. Vac. Sci. Technol. B
11
, 1472
(1993
). 38.
G.
Lengel
, R.
Wilkins
, M.
Weimer
, J.
Gryko
, and R.
Allen
, in 22nd International Conference on the Physics of Semiconductors, edited by D. Lockwood (World Scientific, Singapore, 1995), Vol. 1, pp. 479–484.39.
Y.
Ishikawa
, N.
Tsurumi
, T.
Fukui
, and H.
Hasegawa
, J. Vac. Sci. Technol. B
16
, 2387
(1998
). 40.
M.
Schnedler
, V.
Portz
, P. H.
Weidlich
, R. E.
Dunin-Borkowski
, and Ph.
Ebert
, Phys. Rev. B
91
, 235305
(2015
). 41.
M.
Schnedler
, R. E.
Dunin-Borkowski
, and Ph.
Ebert
, Phys. Rev. B
93
, 195444
(2016
). 42.
J.
Bono
and R. H.
Good
, Surf. Sci.
175
, 415
(1986
). 43.
R. M.
Feenstra
and J. A.
Stroscio
, J. Vac. Sci. Technol. B
5
, 923
(1987
). 44.
M.
Heinrich
, C.
Domke
, Ph.
Ebert
, and K.
Urban
, Phys. Rev. B
53
, 10894
(1996
). 45.
M.
Heinrich
, “Mechanismen der Desorption und Entmischung auf Indiumphosphid (110)-Oberflächen bei thermischer Behandlung,” Ph.D. thesis (RWTH Aachen, Juel-3385, Forschungszentrum Jülich, 1997).46.
R. J.
Pechman
, X.-S.
Wang
, and J. H.
Weaver
, Phys. Rev. B
51
, 10929
(1995
). 47.
M.
Hjort
, J. V.
Knutsson
, B.
Mandl
, K.
Deppert
, E.
Lundgren
, R.
Timm
, and A.
Mikkelsen
, Nanoscale
7
, 9998
(2015
). 48.
D. S.
Rosenzweig
, M. N. L.
Hansemann
, M.
Schnedler
, Ph.
Ebert
, and H.
Eisele
, Phys. Rev. Mater.
6
, 124603
(2022
). 49.
C. T.
Foxon
, B. A.
Joyce
, R. F. C.
Farrow
, and R. M.
Griffiths
, J. Phys. D: Appl. Phys.
7
, 2422
(1974
). 50.
B.
Goldstein
, D. J.
Szostak
, and V. S.
Ban
, Surf. Sci.
57
, 733
(1976
). 51.
F.
Proix
, A.
Akremi
, and Z. T.
Zhong
, J. Phys. C: Solid State Phys.
16
, 5449
(1983
). 52.
S.
Kaku
and J.
Yoshino
, Small
16
, 2002296
(2020
). 53.
J. N.
Shapiro
, A.
Lin
, D. L.
Huffaker
, and C.
Ratsch
, Phys. Rev. B
84
, 085322
(2011
). 54.
S. R.
McKibbin
et al., Nano Lett.
20
, 887
(2020
). 55.
Ph.
Ebert
, M.
Heinrich
, M.
Simon
, K.
Urban
, and M. G.
Lagally
, Phys. Rev. B
51
, 9696
(1995
). 56.
Ph.
Ebert
, K.
Urban
, L.
Aballe
, C. H.
Chen
, K.
Horn
, G.
Schwarz
, J.
Neugebauer
, and M.
Scheffler
, Phys. Rev. Lett.
84
, 5816
(2000
). 57.
U.
Semmler
, M.
Simon
, Ph.
Ebert
, and K.
Urban
, J. Chem. Phys.
114
, 445
(2001
). 58.
R. M.
Feenstra
, Phys. Rev. Lett.
63
, 1412
(1989
). 59.
The band edge positions are determined erroneously from tunneling spectra in Ref. 11 by assuming no pinning through defects and, thus, a large tip-induced band bending. However, a logarithmic display of the same tunnel current data corrected for the used ramp in tip-sample separation reveals a valence band current onset at
V, a defect current at small positive voltages and a conduction band current onset at +1 V, hence yielding a correct bandgap and indicating rather a full pinning.
60.
K. A.
Dick
, P.
Caroff
, J.
Bolinsson
, M. E.
Messing
, J.
Johansson
, K.
Deppert
, L. R.
Wallenberg
, and L.
Samuelson
, Semicond. Sci. Technol.
25
, 024009
(2010
). 61.
Ph.
Ebert
, C.
Domke
, and K.
Urban
, Appl. Phys. Lett.
78
, 480
(2001
). 62.
W.
Mönch
, Semiconductor Surfaces and Interfaces
, 3rd ed.
(Springer
, Berlin
, 2001
).63.
R. W.
Jansen
and O. F.
Sankey
, Phys. Rev. B
39
, 3192
(1989
). 64.
J. E.
Northrup
and S. B.
Zhang
, Phys. Rev. B
47
, 6791
(1993
). 2023 Published under an exclusive license by the AVS.
2023
Author(s)
You do not currently have access to this content.
