The adsorption of nitrogen (N) radicals (nitridation) on InAs (001) surfaces has been studied by ultrahigh-vacuum scanning tunneling microscopy and x-ray photoelectronic spectroscopy. The nitridation proceeds as Langmuir adsorption. The N adsorption at 350 °C is faster than that at 100 °C, but N adsorption rates at 100 °C on InAs and GaAs are almost the same. These results are explained as follows: at 350 °C, N radicals bond mainly with the topmost In atoms on an In-stabilized surface, and at 100 °C, N radicals replace As atoms in the topmost layer on an As-stabilized surface, and subsequently bond with In atoms in the second layer. The amorphous 100 °C nitrided surface layer is found to have an insulating characteristic without surface states.

Topics
X-rays, Metallurgy, Scanning tunneling microscopy, Nitrides, Chemical elements, Adsorption, Spectroscopy, Semiconductors
1.
R.
Notzel
,
J.
Temmyo
, and
T.
Tamamura
,
Nature (London)
369
,
131
(
1994
).
Google Scholar
Crossref
Search ADS
 
2.
M.
Kasu
,
T.
Makimoto
, and
N.
Kobayashi
,
Jpn. J. Appl. Phys., Part 1
36
,
3821
(
1997
).
Google Scholar
Crossref
Search ADS
 
3.
S. M. Sze, Physics of Semiconductor Devices (Wiley, New York, 1981), p. 248; in the calculation we assumed a built-in potential of 0.8 V.
4.
T.
Gemmeren
,
S. R.
Salmagne
, and
W.
Monch
,
Appl. Surf. Sci.
65/66
,
625
(
1993
).
Google Scholar
Crossref
Search ADS
 
5.
M.
Kasu
,
T.
Makimoto
, and
N.
Kobayashi
,
Appl. Phys. Lett.
68
,
955
(
1996
).
Google Scholar
Crossref
Search ADS
 
6.
M.
Kasu
,
T.
Makimoto
, and
N.
Kobayashi
,
Appl. Phys. Lett.
70
,
1161
(
1997
).
Google Scholar
Crossref
Search ADS
 
7.
During cooling of the sample from 350 °C to RT, In-stabilized (4×2) surface was changed to As-stabilized (2×4) surface by background As adsorption.
8.
R. J.
Hauenstein
,
D. A.
Collins
,
X. P.
Cai
,
M. L.
O’Steen
, and
T. C.
McGill
,
Appl. Phys. Lett.
66
,
2861
(
1995
).
Google Scholar
Crossref
Search ADS
 
9.
O.
Brandt
,
H.
Yang
,
B.
Jenichen
,
Y.
Suzuki
,
L.
Daweritz
, and
K. H.
Ploog
,
Phys. Rev. B
52
,
R2253
(
1995
).
Google Scholar
Crossref
Search ADS
 
10.
S.
Gwo
,
H.
Tokumoto
, and
S.
Maw
,
Appl. Phys. Lett.
71
,
362
(
1997
).
Google Scholar
Crossref
Search ADS
 
11.
Amorphous nitrided GaAs was formed at 250 °C in Ref. 2, and at 100 °C here. It seems that amorphous phase in 100 °C nitrided GaAs surface was more than that in 250 °C nitrided GaAs surface.
12.
J. A. Stroscio and R. M. Feenstra, Scanning Tunneling Microscopy, edited by J. A. Stroscio (Academic, San Diego, 1993), p. 95.
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© 1998 American Institute of Physics.
1998
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