A high concentration of radicals is present in many processing plasmas, which affects the processing conditions and the properties of materials exposed to the plasma. Determining the types and concentrations of free radicals present in the plasma is critical in order to determine their effects on the materials being processed. Current methods for detecting free radicals in a plasma require multiple expensive and bulky instruments, complex setups, and often, modifications to the plasma reactor. This work presents a simple technique that detects reactive-oxygen radicals incident on a surface from a plasma. The measurements are made using a fluorophore dye that is commonly used in biological and cellular systems for assay labeling in liquids. Using fluorometric analysis, it was found that the fluorophore reacts with oxygen radicals incident from the plasma, which is indicated by degradation of its fluorescence. As plasma power was increased, the quenching of the fluorescence significantly increased. Both immobilized and nonimmobilized fluorophore dyes were used and the results indicate that both states function effectively under vacuum conditions. The reaction mechanism is very similar to that of the liquid dye.

1.
F. F.
Chen
,
Introduction to Plasma Physics and Controlled Fusion
, 3rd ed. (
Plenum
,
New York
,
1984
).
2.
F. F.
Chen
,
Plasma Phys.
2
,
2164
(
1995
).
3.
T.
Standaert
,
P. J.
Matsuo
,
S. D.
Allen
,
G. S.
Oehrlein
,
T. J.
Dalton
,
T. M.
Lu
, and
R.
Gutmann
,
MRS Proceedings
(
Cambridge University
, Cambridge, UK,
1998
), Vol.
511
, p.
367
.
4.
M.
Hori
and
T.
Goto
,
Plasma Sources Sci. Technol.
15
,
S74
(
2006
).
5.
C. S.
Moon
,
K.
Takeda
,
S.
Takashima
,
M.
Sekine
,
Y.
Setsuhara
,
M.
Shiratani
, and
M.
Hori
,
J. Appl. Phys.
107
,
103310
(
2010
).
6.
H.
Shi
,
H.
Huang
,
J.
Bao
,
J.
Liu
,
P. S.
Ho
,
Y.
Zhou
,
J. T.
Pender
,
M. D.
Armacost
, and
D.
Kyser
,
J. Vac. Sci. Technol. B
30
,
011206
(
2012
).
7.
M. A.
Goldman
,
D. B.
Graves
,
G. A.
Antonelli
,
S. P.
Behera
, and
J. A.
Kelber
,
J. Appl. Phys.
106
,
013311
(
2009
).
8.
J.
Lee
and
D. B.
Graves
,
J. Vac. Sci. Technol. A
31
,
041302
(
2013
).
9.
J.
Bao
,
H.
Shi
,
H.
Huang
,
P. S.
Ho
,
M. L.
McSwiney
,
M. D.
Goodner
,
M.
Moinpour
, and
G. M.
Kloster
, J.
Vac. Sci. Technol. A
28
,
207
(
2010
).
10.
Y. H.
Kim
,
Y. J.
Hong
,
K. Y.
Baik
,
G. C.
Kwon
,
J. J.
Choi
,
G. S.
Cho
,
H. S.
Uhm
,
D. Y.
Kim
, and
E. H.
Choi
,
Plasma Chem. Plasma Process.
34
,
457
(
2014
).
11.
P.
Wardman
,
Free Radical Biol. Med.
43
,
995
(
2007
).
13.
J.
Liu
,
C.
Liu
, and
W.
He
,
Current Organic Chemistry
(
Bentham Science
, U.A.E.,
2013
), p.
564
.
14.
J. R.
Lakowicz
,
Principles of Fluorescence Spectroscopy
, 3rd ed. (
Springer
,
Berlin
,
2006
).
15.
A.
Simeonov
 et al.,
J. Med. Chem.
51
,
2363
(
2008
).
16.
N.
Panchuk-Voloshina
,
R. P.
Haugland
,
J.
Bishop-Stewart
,
M. K.
Bhalgat
,
P. J.
Millard
,
F.
Mao
,
W. Y.
Leung
, and
R. P.
Haugland
,
J. Histochem. Cytochem.
47
,
1179
(
1999
).
17.
J. E.
Berlier
 et al.,
J. Histochem. Cytochem.
51
,
1699
(
2003
).
18.
E.
Rusinova
,
V.
Tretyachenko-Ladokhina
,
O. E.
Vele
,
D. F.
Senear
, and
J. B.
Alexander Ross
,
Anal. Biochem.
308
,
18
(
2002
).
19.
A.
Schwartz
,
L.
Wang
,
E.
Early
,
A.
Gaigalas
,
Y.-Z.
Zhang
,
E. G.
Marti
, and
F. R.
Vogt
,
J. Res. Natl. Inst. Stand. Technol.
107
,
83
(
2002
).
21.
M.
Schena
,
D.
Shalon
,
W. R.
Davis
, and
O. P.
Brown
,
Science
270
,
467
(
1995
).
22.
J. D.
Duggan
,
M.
Bittner
,
D. Y.
Chen
,
P.
Meltzer
, and
M. J.
Trent
,
Nat. Genet.
21
,
10
(
1999
).
23.
G.
Hardiman
,
Microarray Methods and Applications
(
DNA Press Inc.
, Eagleville, PA,
2003
).
24.
M.
Schena
,
Microarray Biochip Technology
(
Eaton Publishing, Natick, MA
,
2000
).
25.
H.
Zhu
,
M.
Bilgin
,
R.
Bangham
,
D.
Hall
,
A.
Casamayor
,
P.
Bertone
,
N.
Lan
, and
R.
Jansen
,
Science
293
,
2101
(
2001
).
26.
G.
MacBeath
and
L. S.
Schreiber
,
Science
289
,
1760
(
2000
).
27.
Y. J.
Rao
,
D.
Seligson
, and
P. G.
Hemstreet
,
BioTechniques
32
,
924
(
2002
).
28.
L.
Wang
,
A. K.
Gaigalas
, and
V.
Reipa
,
BioTechniques
38
,
127
(
2005
).
29.
H. F.
Dobele
,
Plasma Sources Sci. Technol.
4
,
224
(
1995
).
30.
M. T.
Nichols
, “
The Effects of Processing Induced Damage on Electrical Conduction Mechanisms and Time-Dependent Dielectric Breakdown of Low-k Organosilicates
,” Ph.D. dissertation (
University of Wisconsin-Madison
,
Madison, WI
,
2013
).
31.
M.
Lieberman
and
A.
Lichtenberg
,
Principles of Plasma Discharges and Materials Processing
(
Wiley
,
New York
,
1994
).
32.
C. E.
Aitken
,
R. A.
Marshall
, and
J. D.
Puglisi
,
Biophys. J.
94
,
1826
(
2008
).
33.
W. S.
Choi
,
Y. S.
Yoo
, and
C. W.
Park
,
J. Korean Phys. Soc.
43
,
529
(
2003
).
34.
G. T.
Dempsey
,
J. C.
Vaughan
,
K. H.
Chen
,
M.
Bates
, and
X.
Zhuang
,
Nat. Methods
8
,
1027
(
2011
).
35.
S.
van de Linde
,
S.
Wolter
,
M.
Heilemann
, and
M.
Sauer
,
J. Biotechnol.
149
,
260
(
2010
).
36.
S.
van de Linde
,
I.
Krstic
,
T.
Prisner
,
S.
Doose
,
M.
Heilemann
, and
M.
Sauer
,
Photochem. Photobiol. Sci.
10
,
499
(
2011
).
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