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US6054016A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetically enhanced microwave plasma generating apparatus

Assignee: Mitsubishi Electric Engineering Co Ltd
•
Filing: 1998-02-27
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Granted: 2000-04-25
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Expires: 2018-02-27
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Abstract

Abstract There is provided a plasma generating apparatus comprising: a waveguide for guiding a microwave; a vacuum vessel connected to the waveguide, having a means for supplying a gas for discharging electrons and a means for evacuating; and a dielectric member in a tube-like shape or a rod-like shape which is inserted in the vacuum vessel, wherein the dielectric member is provided with a means for emitting the microwave, whereby it is possible to apply the electric power of microwave effectively to plasma of high density exceeding so-called cut-off density and to homogenize the distribution of plasma in the vacuum vessel.

Inventors

  • 👤 Mutumi Tuda
  • 👤 Kouichi Ono
  • 👤 Masaaki Tsuchihashi
  • 👤 Minoru Hanazaki
  • 👤 Toshio Komemura
  • 👤 Kouji Oku
  • 👤 Shinji Nakaguma

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 02:32
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32192; H01J37/32211; H01J37/3222; H01J37/32431; H01J37/3266; H01J37/32688; H05; H05H; H05H1/00; H05H1/24; H05H1/46

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 97 words
A plasma generating apparatus comprising: a waveguide for guiding microwaves; a vacuum vessel connected to the waveguide, having a means for supplying a gas to the vacuum vessel for discharging electrons and a means for evacuating the vacuum vessel; a dielectric member having a tube-like shape or a rod-like shape, extending into the vacuum vessel, and comprising means for emitting microwaves; and means, disposed outside of the vacuum vessel, for generating a first magnetic field inside the vacuum vessel such that the dielectric member is in a relatively weak magnetic field region of the first magnetic field.
Claim 2
Dependent Claim 97 words
A plasma generating apparatus comprising: a waveguide for guiding microwaves; a vacuum vessel connected to the waveguide, having a means for supplying a gas to the vacuum vessel for discharging electrons and a means for evacuating the vacuum vessel; a dielectric member having a tube-like shape or a rod-like shape, extending into the vacuum vessel, and comprising means for emitting microwaves; and means, disposed outside of the vacuum vessel, for generating a first magnetic field inside the vacuum vessel such that the dielectric member is in a relatively weak magnetic field region of the first magnetic field.
Claim 3
Dependent Claim 27 words
The plasma generating apparatus according to claim 1, wherein the means for emitting microwaves is a slit or an antenna provided in a wall of the waveguide.
Claim 4
Dependent Claim 21 words
The plasma generating apparatus according to claim 1, wherein the dielectric member comprises a dielectric material through which microwaves are permeable.
Claim 5
Dependent Claim 30 words
The plasma generating apparatus according to claim 1, wherein the dielectric member is located in a weak magnetic field region having a magnetic field strength of 100 G or less.
Claim 6
Dependent Claim 24 words
The plasma generating apparatus according to claim 1, wherein the weak magnetic field region has a magnetic field strength of 100 G or less.
Claim 7
Dependent Claim 35 words
The plasma generating apparatus according to claim 1, wherein the first magnetic field has a magnetic field strength sufficient to cause an electron cyclotron resonance and to start a discharge using the electron cyclotron resonance.
Claim 8
Dependent Claim 20 words
The plasma generating apparatus according to claim 1, wherein the means for generating a magnetic field is a permanent magnet.
Claim 9
Dependent Claim 43 words
The plasma generating apparatus according to claim 1, further comprising an electromagnetic coil for generating a component of a second magnetic field to be superposed on a component of the first magnetic field, the electromagnetic coil being disposed outside of the vacuum vessel.
Claim 10
Dependent Claim 22 words
The plasma generating apparatus according to claim 3, wherein the dielectric member comprises at least one of quartz, glass, polytetrafluoroethylene and ceramic.

References Cited (Backward Citations)

US4265730A Cited
US4831963A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-04-25 2003-10-25 2004-04-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-04-25 2007-10-25 2008-04-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-04-25 2011-10-25 2012-04-25 $7700.00 Window Closed / Lapsed

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