An experimental investigation of electrode voltage/discharge current, plasma density, including negative ions and ion flux, and ion energy distributions (IEDs) is performed in a low-pressure oxygen discharge excited by a multi-tile electrode, very high frequency (162 MHz) capacitively coupled plasma system. The results show a mode transition vs RF power. An inflection point is observed in the measured electrode voltage and current near to the mode transition. The negative ion density inferred from the measured electron density and ion flux using resonance hairpin probe and planar probe, respectively, shows an initial increase and then decrease after mode transition. The IED shows a symmetric narrow distribution and the mean energy first increases up to the transition point and then decreases with further increase in RF power. A change in the current coupling mechanism and variation in the discharge impedance due to the presence of negative ions are responsible for the observed mode transition.
References
1.
H.
Curtins
, N.
Wyrsch
, M.
Favre
, and A. V. I.
Shah
, “Influence of plasma excitation frequency for a-Si:H thin film deposition
,” Plasma Chem. Plasma Process.
7
(3
), 267
(1987
).2.
A. A.
Howling
, “Frequency effects in silane plasmas for plasma enhanced chemical vapor deposition
,” J. Vac. Sci. Technol., A
10
(4
), 1080
(1992
).3.
M.
Meyyappan
and M. J.
Colgan
, “Very high frequency capacitively coupled discharges for large area processing
,” J. Vac. Sci. Technol., A
14
(5
), 2790
(1996
).4.
V.
Vahedi
, C. K.
Birdsall
, M. a
Lieberman
, G.
DiPeso
, and T. D.
Rognlien
, “Verification of frequency scaling laws for capacitive radio-frequency discharges using two-dimensional simulations
,” Phys. Fluids B
5
(7
), 2719
(1993
).5.
M.
Surendra
and D. B.
Graves
, “Capacitively coupled glow discharges at frequencies above 13.56 MHz
,” Appl. Phys. Lett.
59
(17
), 2091
(1991
).6.
W.
Schwarzenbach
, A. A.
Howling
, M.
Fivaz
, S.
Brunner
, and C.
Hollenstein
, “Sheath impedance effects in very high frequency plasma experiments
,” J. Vac. Sci. Technol., A
14
(1
), 132
(1996
).7.
K. M.
Kalpakjian
, “High frequency reactive ion etching of silylated photoresist
,” J. Vac. Sci. Technol., B
12
(3
), 1351
(1994
).8.
A.
Perret
, P.
Chabert
, J. P.
Booth
, J.
Jolly
, J.
Guillon
, and P.
Auvray
, “Ion flux nonuniformities in large-area high-frequency capacitive discharges
,” Appl. Phys. Lett.
83
(2
), 243
(2003
).9.
X.-M.
Zhu
, W.-C.
Chen
, S.
Zhang
, Z.-G.
Guo
, D.-W.
Hu
, and Y.-K.
Pu
, “Electron density and ion energy dependence on driving frequency in capacitively coupled argon plasmas
,” J. Phys. D: Appl. Phys.
40
(22
), 7019
(2007
).10.
B. G.
Heil
, U.
Czarnetzki
, R. P.
Brinkmann
, and T.
Mussenbrock
, “On the possibility of making a geometrically symmetric RF-CCP discharge electrically asymmetric
,” J. Phys. D: Appl. Phys.
41
(16
), 165202
(2008
).11.
J.
Meichsner
, M.
Zeuner
, B.
Krames
, M.
Nitschke
, R.
Rochotzki
, and K.
Barucki
, “Plasma diagnostics for surface modification of polymers
,” Surf. Coat. Technol.
98
(1–3
), 1565
(1998
).12.
A.
Hallil
, O.
Zabeida
, M. R.
Wertheimer
, and L.
Martinu
, “Mass-resolved ion energy distributions in continuous dual mode microwave/radio frequency plasmas in argon and nitrogen
,” J. Vac. Sci. Technol., A
18
(3
), 882
(2000
).13.
E.
Kawamura
, V.
Vahedi
, M. A.
Lieberman
, and C. K.
Birdsall
, “Ion energy distributions in rf sheaths; review, analysis and simulation
,” Plasma Sources Sci. Technol.
8
(3
), R45
(1999
).14.
M. A.
Lieberman
, J. P.
Booth
, P.
Chabert
, J. M.
Rax
, and M. M.
Turner
, “Standing wave and skin effects in large-area, high-frequency capacitive discharges
,” Plasma Sources Sci. Technol.
11
, 283
(2002
).15.
16.
E.
Monaghan
, T.
Michna
, C.
Gaman
, D.
O'Farrel
, K.
Ryan
, D.
Adley
, T. S.
Perova
, B.
Drews
, M.
Jaskot
, and A. R.
Ellingboe
, “Characterisation of thin film silicon films deposited by plasma enhanced chemical vapour deposition at 162 MHz, using a large area, scalable, multi-tile-electrode plasma source
,” Thin Solid Films
519
(20
), 6884
(2011
).17.
K. S.
Kim
, N.
Sirse
, K. H.
Kim
, A. R.
Ellingboe
, K. N.
Kim
, and G. Y.
Yeom
, “Characteristics of silicon nitride deposited by VHF (162 MHz)-plasma enhanced chemical vapor deposition using a multi-tile push–pull plasma source
,” J. Phys. D: Appl. Phys.
49
(39
), 395201
(2016
).18.
Y.
Kawai
, N.
Konishi
, J.
Watanabe
, and T.
Ohmi
, “Ultra-low-temperature growth of high-integrity gate oxide films by low-energy ion-assisted oxidation
,” Appl. Phys. Lett.
64
(17
), 2223
(1994
).19.
A.
Vesel
and M.
Mozetic
, “New developments in surface functionalization of polymers using controlled plasma treatments
,” J. Phys. D: Appl. Phys.
50
(29
), 293001
(2017
).20.
N. Y.
Babaeva
, J. K.
Lee
, J. W.
Shon
, and E. A.
Hudson
, “Oxygen ion energy distribution: Role of ionization, resonant, and nonresonant charge-exchange collisions
,” J. Vac. Sci. Technol., A
23
(4
), 699
(2005
).21.
Y.
Jin
, K.
Seok Kim
, A. R.
Ellingboe
, and G.
Young
, “Nitriding process for next-generation semiconductor devices by VHF (162 MHz) multi-tile push-pull plasma source
,” Appl. Surf. Sci.
506
, 144904
(2020
).22.
S. B. S.
Heil
, P.
Kudlacek
, E.
Langereis
, R.
Engeln
, M. C. M.
Van De Sanden
, and W. M. M.
Kessels
, “In situ reaction mechanism studies of plasma-assisted atomic layer deposition of Al2O3
,” Appl. Phys. Lett.
89
(13
), 131505
(2006
).23.
N.
Sirse
, C.
Harvey
, and A. R.
Ellingboe
, “Investigation of plasma uniformity, rotational and vibrational temperature in a 162 MHz multi-electrode capacitive discharge
,” J. Phys. D: Appl. Phys.
53
, 335203
(2020
).24.
T.
Michna
and A. R.
Ellingboe
, “Characterisation of an RF power splitter for multi-tile PECVD systems application
,” Curr. Appl. Phys.
11
(5 Suppl
), S9
–S11
(2011
).25.
R. L.
Stenzel
, “Microwave resonator probe for localized density measurements in weakly magnetized plasmas
,” Rev. Sci. Instrum.
47
(5
), 603
(1976
).26.
R. B.
Piejak
, V. A.
Godyak
, R.
Garner
, B. M.
Alexandrovich
, and N.
Sternberg
, “The hairpin resonator: A plasma density measuring technique revisited
,” J. Appl. Phys.
95
(7
), 3785
(2004
).27.
S. K.
Karkari
, C.
Gaman
, A. R.
Ellingboe
, I.
Swindells
, and J. W.
Bradley
, “A floating hairpin resonance probe technique for measuring time-resolved electron density in pulse discharge
,” Meas. Sci. Technol.
18
(8
), 2649
(2007
).28.
P.
Chabert
, T. E.
Sheridan
, R. W.
Boswell
, and J.
Perrin
, “Electrostatic probe measurement of the negative ion fraction in an SF_6 helicon discharge
,” Plasma Sources Sci. Technol.
8
, 561
(1999
).29.
U.
Kortshagen
, N. D.
Gibson
, and J. E.
Lawler
, “On the E-H mode transition in RF inductive discharges
,” J. Phys. D: Appl. Phys.
29
(5
), 1224
(1996
).30.
A. R.
Ellingboe
and R. W.
Boswell
, “Capacitive, inductive and helicon-wave modes of operation of a helicon plasma source
,” Phys. Plasmas
3
(7
), 2797
(1996
).31.
I.
Ghanashev
, M.
Nagatsu
, G.
Xu
, and H.
Sugai
, “Mode jumps and hysteresis in surface-wave sustained microwave discharges
,” Jpn. J. Appl. Phys., Part 1
36
(7 Suppl. B
), 4704
(1997
).32.
H.
Deutsch
, P.
Scheier
, K.
Becker
, and T. D.
Märk
, “Calculated cross-sections for the electron-impact detachment from negative ions using the Deutsch-Märk (DM) formalism
,” Chem. Phys. Lett.
382
(1–2
), 26
(2003
).33.
V.
Laporta
, R.
Celiberto
, and J.
Tennyson
, “Dissociative electron attachment and electron-impact resonant dissociation of vibrationally excited O2 molecules
,” Phys. Rev. A
91
(1
), 1
(2015
).34.
J. K.
Olthoff
, R. J.
Van Brunt
, S. B.
Radovanov
, J. A.
Rees
, and R.
Surowiec
, “Kinetic-energy distributions of ions sampled from argon plasmas in a parallel-plate, radio-frequency reference cell
,” J. Appl. Phys.
75
(1
), 115
(1994
).35.
Z.
Donkó
, J.
Schulze
, U.
Czarnetzki
, A.
Derzsi
, P.
Hartmann
, I.
Korolov
, and E.
Schüngel
, “Fundamental investigations of capacitive radio frequency plasmas: Simulations and experiments
,” Plasma Phys. Controlled Fusion
54
(12
), 124003
(2012
).36.
J. K.
Lee
, O. V.
Manuilenko
, N. Y.
Babaeva
, H. C.
Kim
, and J. W.
Shon
, “Ion energy distribution control in single and dual frequency capacitive plasma sources
,” Plasma Sources Sci. Technol.
14
(1
), 89
(2005
).37.
D.
O'Connell
, R.
Zorat
, A. R.
Ellingboe
, and M. M.
Turner
, “Comparison of measurements and particle-in-cell simulations of ion energy distribution functions in a capacitively coupled radio-frequency discharge
,” Phys. Plasmas
14
(10
), 103510
(2007
).38.
J.
Liu
, Q.-Z.
Zhang
, Y.-X.
Liu
, F.
Gao
, and Y.-N.
Wang
, “Measurements of ion energy distributions in a dual-frequency capacitively coupled plasma for Ar/O 2 discharges
,” J. Phys. D: Appl. Phys.
46
(23
), 235202
(2013
).39.
D.
Gahan
, S.
Daniels
, C.
Hayden
, D. O.
Sullivan
, and M. B.
Hopkins
, “Characterization of an asymmetric parallel plate radio-frequency discharge using a retarding field energy analyzer
,” Plasma Sources Sci. Technol.
21
(1
), 015002
(2012
).40.
K.
Ryan
, “Spatial diagnostics of plasma produced by a VHF multi-tile electrode
,” Masters Dissertation (Dublin City University
, 2012
).© 2020 Author(s).
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