Two-dimensional temperature maps of reactive gas layers were produced using pulsed laser Rayleigh scattering thermometry. The measurements were made in conditions of diamond film chemical vapor deposition (CVD) using a thermal inductively coupled plasma. In these conditions, the reactive gas layer is typically a few millimeters thick and the temperature drops across the layer from 4000 K at the free stream boundary to about 1200 K at the substrate. The reactive layer exhibits strong chemical nonequilibrium. Rayleigh scattering was induced using a pulsed laser sheet at 532 nm wavelength. The scattered radiation was detected and calibrated with an intensified charge coupled device camera. Temperature maps and axial profiles obtained under parametric variation of the gas flow conditions demonstrate how the technique can be employed to measure the reactive layer thickness and its radial distribution across the substrate. The results demonstrate that imaging Rayleigh scattering thermometry can be employed as a nonintrusive diagnostic tool to obtain useful experimental information pertinent to the gas phase chemistry in diamond CVD under conditions of extremely large temperature gradients.

1.
M. A.
Cappelli
,
T. G.
Owano
,
M.
Gordon
, and
C. H.
Kruger
,
J. Mater. Res.
5
,
2326
(
1990
).
2.
S.
Matsumoto
,
M.
Hino
, and
T.
Kobayashi
,
Appl. Phys. Lett.
51
,
737
(
1987
).
3.
R.
Hernberg
,
T.
Lepistö
,
T.
Mäntylä
,
T.
Stenberg
, and
J.
Vattulainen
,
Diam. Relat. Mater.
1
,
255
(
1992
).
4.
M.
Kohzaki
,
K.
Uchida
,
K.
Higuchi
, and
S.
Noda
,
Jpn. J. Appl. Phys.
32
,
L438
(
1993
).
5.
S. L.
Girshick
,
C.
Li
,
B. W.
Yu
, and
H.
Han
,
Plasma Chem. Plasma Process.
13
,
169
(
1993
).
6.
I.
Namer
and
R. W.
Schefer
,
Exp. Fluids
3
,
1
(
1985
).
7.
R. W. Dibble and R. E. Hollenbach, 18th International Symposium Combustion (The Combustion Institute, Pittsburgh, 1981).
8.
R. B.
Barat
,
J. P.
Longwell
,
A. F.
Sarofim
,
S. P.
Smith
, and
E.
Bar-Ziv
,
Appl. Opt.
30
,
3003
(
1991
).
9.
P.
Gölz
, and
P.
Andresen
,
Appl. Opt.
35
,
6054
(
1996
).
10.
N.
Bryner
,
C. D.
Richards
, and
W. M.
Pitts
,
Rev. Sci. Instrum.
63
,
3629
(
1992
).
11.
A. J. D.
Farmer
and
G. N.
Haddad
,
J. Phys. D
21
,
426
(
1988
).
12.
Z.
Wang
and
R. J.
Kearney
,
J. Quant. Spectrosc. Radiat. Transf.
44
,
339
(
1990
).
13.
S. C.
Snyder
,
L. D.
Reynolds
,
C. B.
Shaw
, and
R. J.
Kearney
,
J. Quant. Spectrosc. Radiat. Transf.
46
,
119
(
1991
).
14.
A.
Gicquel
,
K.
Hassouni
,
Y.
Breton
,
M.
Chenevier
, and
J. C.
Cubertafon
,
Diam. Relat. Mater.
5
,
366
(
1996
).
15.
K-H.
Chen
,
M-C.
Chuang
,
C. M.
Penney
, and
W. F.
Banholzer
,
J. Appl. Phys.
71
,
1485
(
1992
).
16.
C. F.
Kaminski
and
P.
Ewart
,
Appl. Phys. B
64
,
103
(
1997
).
17.
S. K. Baldwin, T. G. Owano, M. Zhao, and C. H. Kruger, in Diamond ’96, Tours, France, 1996 (unpublished).
18.
J.
Larjo
,
J.
Vattulainen
, and
R.
Hernberg
,
Appl. Phys. B
62
,
71
(
1996
).
19.
T. G. Owano, E. H. Wahl, and C. H. Kruger In 11th Int. Symp. on Plasma Chemistry, Loughborough, 1993 (unpublished).
20.
D. S.
Green
,
T. G.
Owano
,
S.
Williams
,
D. G.
Goodwin
,
R. N.
Zare
, and
C. H.
Kruger
,
Science
259
,
1736
(
1993
).
21.
E. H.
Wahl
,
T. G.
Owano
,
C. H.
Kruger
,
P.
Zalicki
,
Y.
Ma
, and
R. N.
Zare
,
Diam. Relat. Mater.
5
,
373
(
1996
).
22.
M. H.
Loh
and
M. A.
Cappelli
,
Appl. Phys. Lett.
70
,
1052
(
1997
).
23.
L.
Schäfer
,
C.-P.
Klages
,
U.
Meier
, and
K.
Kohse-Höinghaus
,
Appl. Phys. Lett.
58
,
571
(
1991
).
24.
K.
Donnelly
,
D. P.
Dowling
,
T. P.
O’Brien
,
A.
O’Leary
,
T. C.
Kelly
,
R.
Cheshire
,
K. F.
Al-Assadi
,
W. G.
Graham
,
T.
Morrow
,
V.
Kornas
,
V.
Schultz-von der Gathen
, and
H. F.
Döbele
,
Diam. Relat. Mater.
4
,
324
(
1995
).
25.
F. G.
Celii
and
J. E.
Butler
,
J. Appl. Phys.
71
,
2877
(
1992
).
26.
P. B.
Davies
and
P. M.
Martineau
,
J. Appl. Phys.
71
,
6125
(
1992
).
27.
B. W.
Yu
and
S. L.
Girshick
,
J. Appl. Phys.
75
,
3194
(
1994
).
28.
D. G.
Goodwin
,
J. Appl. Phys.
74
,
6888
(
1993
).
29.
J. Vattulainen and R. Hernberg, in 11th International Symposium on Plasma Chemistry, Loughborough, 1993 (unpublished).
30.
M. T.
Bieberich
and
S. L.
Girshick
,
Plasma Chem. Plasma Process.
16
,
157S
(
1996
).
31.
R. P. Benedict, Fundamentals of Pipe Flow (Wiley, New York, 1980).
32.
D. G.
Goodwin
,
J. Appl. Phys.
74
,
6895
(
1993
).
33.
M. I. Boulos, P. Fauchais, and E. Pfender, Thermal Plasmas: Fundamentals and Applications (Plenum, New York, 1994), Vol. 1.
34.
H. Schlichting, Boundary-Layer Theory, 7th ed. (McGraw-Hill, New York, 1979).
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