The authors present molecular dynamics (MD) simulations of energetic Ar+ ions (20200eV) interacting with initially crystalline silicon, with quantitative comparison to experiment. Ar+ bombardment creates a damaged or amorphous region at the surface, which reaches a steady-state thickness that is a function of the impacting ion energy. Real-time spectroscopic ellipsometry data of the same phenomenon match the MD simulation well, as do analogous SRIM simulations. They define positional order parameters that detect a sharp interface between the amorphous and crystalline regions. They discuss the formation of this interesting feature in the simulation, and show that it provides insight into some assumptions made in the analysis of experimental data obtained by interface-sensitive surface spectroscopy techniques.

1.
H. F.
Winters
and
J. W.
Coburn
,
Surf. Sci. Rep.
14
,
161
(
1992
) and references therein.
2.
J. P.
Chang
and
H. H.
Sawin
,
J. Vac. Sci. Technol. A
15
,
610
(
1997
).
3.
A. A. E.
Stevens
,
W. M. M.
Kessels
,
M. C. M.
van de Sander
, and
H. C. W.
Beijerinck
,
J. Vac. Sci. Technol. A
24
,
1933
(
2006
).
4.
D. B.
Graves
and
D.
Humbird
,
Appl. Surf. Sci.
192
,
72
(
2002
).
5.
D.
Humbird
and
D. B.
Graves
,
J. Vac. Sci. Technol. A
23
,
31
(
2005
).
6.
J. F.
Ziegler
,
J. P.
Biersack
, and
U.
Littmark
,
The Stopping Range of Ions in Solids
(
Pergamon
,
Oxford
,
1985
).
7.
T. A.
Schoolcraft
, in
23rd International Symposium on Dry Process Conference Proceedings
(
The Institute of Electrical Engineers of Japan
,
Tokyo, Japan
,
2001
), pp.
29
36
, and references therein.
8.
L.
Hanley
and
S. B.
Sinnott
,
Surf. Sci.
500
,
500
(
2002
).
9.
G. J. P.
Joosten
,
M. J. M.
Vugts
,
H. J.
Spruijt
,
H. A. J.
Senhorst
, and
H. C. W.
Beijerinck
,
J. Vac. Sci. Technol. A
12
,
636
(
1994
).
10.
M. J. M.
Vugts
,
G. J. P.
Joosten
,
A.
van Oosterum
,
H. A. J.
Senhorst
, and
H. C. W.
Beijerinck
,
J. Vac. Sci. Technol. A
12
,
2999
(
1994
).
11.
A. A. E.
Stevens
and
H. C. W.
Beijerinck
,
J. Vac. Sci. Technol. A
23
,
134
(
2005
).
12.
J. J. H.
Gielis
,
P. M.
Gevers
,
A. A. E.
Stevens
,
H. C. W.
Beijerinck
,
M. C. M.
van de Sanden
, and
W. M. M.
Kessels
,
Phys. Rev. B
74
,
165311
(
2006
).
13.
14.
D.
Humbird
and
D. B.
Graves
,
Pure Appl. Chem.
74
,
419
(
2002
).
15.
F. H.
Stillinger
and
T. A.
Weber
,
Phys. Rev. B
31
,
5262
(
1985
).
16.
W. C.
Swope
,
H. C.
Andersen
,
P. H.
Beren
, and
K. R.
Wilson
,
J. Chem. Phys.
76
,
637
(
1982
).
17.
J. M.
Haile
,
Molecular Dynamics Simulation
(
Wiley
,
New York
,
1992
).
18.
I.
Torrens
,
Interatomic Potentials
(
Academic
,
New York
,
1972
).
19.
H. J. C.
Berendsen
,
J. P. M.
Postma
,
W. F.
van Gunsteren
,
A.
DiNola
, and
J. R.
Haak
,
J. Chem. Phys.
81
,
3684
(
1984
).
20.
D.
Humbird
and
D. B.
Graves
,
J. Appl. Phys.
96
,
791
(
2004
).
21.
H. D.
Hagstrum
,
Phys. Rev.
122
,
83
(
1960
).
22.

From the ellipsometry data it cannot be distinguished whether the thickness of the amorphous layer increases or whether the amorphous fraction of the layer increases with time∕fluence. For simplicity we refer to “an increasing thickness over time∕fluence.”

23.
M. E.
Barone
and
D. B.
Graves
,
J. Appl. Phys.
77
,
1263
(
1995
).
24.
C.
Steinbrüchel
,
Appl. Phys. Lett.
55
,
1960
(
1989
).
25.
W.
Eckstein
,
C.
García-Rosales
,
J.
Roth
, and
J.
László
,
Nucl. Instrum. Methods Phys. Res. B
83
,
95
(
1993
).
26.
D.
Humbird
and
D. B.
Graves
,
Plasma Sources Sci. Technol.
13
,
548
(
2004
).
27.
D.
Humbird
and
D. B.
Graves
,
J. Chem. Phys.
120
,
2405
(
2004
).
You do not currently have access to this content.