A technique for measuring negative-ion density in high-density plasmas used for materials processing has been developed; negative ions were detected by measuring the electron-density perturbation caused by laser photodetachment using a millimeter-wave open resonator. The measured negative-ion density for an inductively-coupled C4F8(5%–20%)/Ar plasma with electron densities around 1011 cm−3 at a pressure of 25 mTorr was comparable to the electron density. The results suggest that species produced via dissociation of C4F8 attaches electrons as effectively as C4F8.

1.
M.
Haverlag
,
A.
Kono
,
D.
Passchier
,
G. M. W.
Kroesen
,
W. J.
Goedheer
, and
F. J.
de Hoog
,
J. Appl. Phys.
70
,
3472
(
1991
).
Google Scholar
 
2.
A.
Kono
,
M.
Endo
,
K.
Ohata
,
S.
Kishimoto
, and
T.
Goto
,
J. Appl. Phys.
76
,
7221
(
1994
).
Google Scholar
 
3.
E.
Stoffels
,
W. W.
Stoffels
,
D.
Vender
,
M.
Kando
,
G. M. W.
Kroesen
, and
F. J.
de Hoog
,
Phys. Rev. E
51
,
2425
(
1995
).
Google Scholar
 
4.
E.
Stoffels
,
W. W.
Stoffels
,
D.
Vender
,
G. M. W.
Kroesen
, and
F. J.
de Hoog
,
J. Vac. Sci. Technol. A
13
,
2051
(
1995
).
Google Scholar
 
5.
T.
Hayashi
,
A.
Kono
, and
T.
Goto
,
Jpn. J. Appl. Phys., Part 1
36
,
4651
(
1997
).
Google Scholar
 
6.
A.
Kono
and
Y.
Ohya
,
Jpn. J. Appl. Phys., Part 1
39
,
1365
(
2000
).
Google Scholar
 
7.
A. Yariv, Optical Electronics (CBS College Publishing New York, 1985), pp. 28–31.
8.
A.
Mandl
,
Phys. Rev. A
3
,
251
(
1971
).
Google Scholar
 
9.
K.
Miyata
,
M.
Hori
, and
T.
Goto
,
J. Vac. Sci. Technol. A
14
,
2343
(
1996
).
Google Scholar
 
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