EP0719447B1
Expired / Lapsed
EP
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Rf plasma reactor
Assignee: Oxford University Innovation Ltd
•
Filing: 1994-09-16
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Granted: 1998-07-22
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Expires: 2014-09-16
Abstract
No abstract record available.
Inventors
- 👤 Beatrice Maria Annaratone
- 👤 John Edward Allen
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 00:02
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32431; H01J37/3244; H01J37/32449; H01J37/32009; H01J37/32018; H01J37/32027; H01J37/32082; H01J37/32137; H01J37/32155; H01J37/32165
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
109 words
A method of generating a plasma in an evacuable chamber
containing a first electrode spaced apart by a separation from a second
electrode, the method comprising the steps of: supplying a gas at a
pressure into the chamber; connecting a first RF power source between
the first and second electrodes so as to generate a glow discharge plasma
with a sheath; and controlling at least one of said pressure, said first RF
power source and said electrode separation so as to generate one or more
voltage gradients in said plasma between the first and second electrodes
characterised by the voltage gradients being generated without an
externally applied magnetic field.
Claim 2
Dependent Claim
14 words
A method as claimed in claim 1, wherein resonance is
generated in the plasma.
Claim 3
Independent Claim
30 words
A method as claimed in any one of the preceding claims,
wherein the electrode separation within the chamber is controlled with
respect to said pressure and first RF power source.
Claim 4
Independent Claim
44 words
A method as claimed in either of claims 1, 2 or 3, comprising
the further step of monitoring an RF current between the first and second
electrodes whilst adjusting at least one of said pressure, said first RF
power source and said electrode separation.
Claim 5
Independent Claim
92 words
A method as claimed in any one of the preceding claims,
wherein the one or more voltage gradients in the plasma are in the form
of a standing wave at a frequency near to the fundamental frequency or
near to an harmonic of the fundamental frequency of the first RF power
source and said method includes the steps of controlling at least one
parameter from the group consisting of said pressure, voltage of said
first RF power source, current of said first RF power source and
electrode separation to maintain said harmonic.
Claim 6
Independent Claim
38 words
A method as claimed in any one of the preceding claims,
further comprising connecting a second RF power source between said
first and second electrodes and superposing the second RF power
source on the first RF power source.
Claim 7
Dependent Claim
35 words
A method as claimed in claim 6, comprising the further step
of synchronously adjusting the frequencies of the first and second RF
power sources and monitoring an RF current between the first and second
electrodes.
Claim 8
Dependent Claim
119 words
A reactor comprising an evacuable chamber (8) having a port
(8a) through which gas is supplied; first and second electrodes (1,2)
located within the chamber and spaced apart from one another by a
separation; pumping means (16) for maintaining sub-atmospheric pressure
of gas supplied through the port (8a); a first RF power source (11,12)
connected between said first and second electrodes (1,2) for generating a
glow discharge plasma and sheath within the chamber (8); and
characterised by means (10, 14, 15) for controlling at least one of said
pressure, said RF power source and electrode separation in order to
generate without an externally applied magnetic field a voltage gradient in
the plasma between the first and second electrodes (1,2).
Claim 9
Dependent Claim
28 words
A reactor as claimed in claim 9, wherein said means for
controlling includes a current monitor (15) for monitoring the current
between the first and second electrodes (1,2).
Claim 10
Dependent Claim
27 words
A reactor as claimed in either of claims 9 or 10, further
including a second RF power source (9,10) connected between said first
and second electrodes (1,2).
Claim 11
Dependent Claim
25 words
A reactor as claimed in claim 10, wherein at least one of the
frequency and voltage of said second RF power source (9,10) is variable.
References Cited (Backward Citations)
No citation records indexed.
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