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US5342472A Expired / Lapsed US ⏱️ 0.0 years remaining

Plasma processing apparatus

Assignee: Tokyo Electron Ltd
•
Filing: 1992-08-12
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Granted: 1994-08-30
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Expires: 2012-08-12
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Abstract

Abstract Microwave inlet ports are formed on a microwave transmission window above a plasma generation chamber. The distance from the microwave inlet ports to a support surface of a wafer support table is set to be an integer multiple of 1/2 the wavelength of the microwave. Upper and lower magnetic poles opposite to each other are arranged above and below the chamber to form a magnetic field having a uniform strength in the chamber. The strength of the magnetic field is set to be 865 Gauss as a value slightly deviating from 875 Gauss as a value satisfying ideal conditions of an electron cyclotron resonance at a microwave wavelength of 2.45 GHz. The electron energy is suppressed, and damage to the surface of a wafer can be suppressed in wafer surface processing using a plasma.

Inventors

  • 👤 Issei Imahashi
  • 👤 Nobuo Ishii

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 23:55
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32192; H01J37/32211; H01J37/32238; H10; H10P; H10P52/00; H01J37/32431; H01J37/3266; H01J37/32678; H01J37/32697; H01J37/32706

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 256 words
An apparatus for generating a plasma by an electron cyclotron resonance and processing a substrate by using this plasma, comprising: a processing chamber; means for setting said chamber in a vacuum atmosphere; a support table disposed in said chamber, said support table having a support surface for supporting the substrate, and said chamber defining a discharge space above said support surface; gas supplying means for supplying a processing gas to be converted into the plasma in said chamber; first and second magnetic poles respectively located on upper and lower sides of the discharge space, and both located outside said chamber, in order to form a magnetic field in the discharge space; means for adjusting the strength of the magnetic field; a microwave transmission window formed in said chamber to oppose the discharge space; a first conductive plate arranged on said microwave transmission window outside said chamber, a plurality of slits formed in said first conductive plate and serving as microwave inlet ports; a dielectric plate adjoining said first conductive plate; a second conductive plate adjoining said dielectric plate with no gap therebetween; and microwave supply means for supplying a microwave to said first conductive plate, and comprising a coaxial line constituted by a central conductor and an outer conductive pipe, an end of said central conductor being guided to a central portion of an upper surface of said dielectric plate without contacting said second conductive plate so as to form transmission paths of the microwave from the central portion to peripheral portions in said dielectric plate.
Claim 2
Independent Claim 256 words
An apparatus for generating a plasma by an electron cyclotron resonance and processing a substrate by using this plasma, comprising: a processing chamber; means for setting said chamber in a vacuum atmosphere; a support table disposed in said chamber, said support table having a support surface for supporting the substrate, and said chamber defining a discharge space above said support surface; gas supplying means for supplying a processing gas to be converted into the plasma in said chamber; first and second magnetic poles respectively located on upper and lower sides of the discharge space, and both located outside said chamber, in order to form a magnetic field in the discharge space; means for adjusting the strength of the magnetic field; a microwave transmission window formed in said chamber to oppose the discharge space; a first conductive plate arranged on said microwave transmission window outside said chamber, a plurality of slits formed in said first conductive plate and serving as microwave inlet ports; a dielectric plate adjoining said first conductive plate; a second conductive plate adjoining said dielectric plate with no gap therebetween; and microwave supply means for supplying a microwave to said first conductive plate, and comprising a coaxial line constituted by a central conductor and an outer conductive pipe, an end of said central conductor being guided to a central portion of an upper surface of said dielectric plate without contacting said second conductive plate so as to form transmission paths of the microwave from the central portion to peripheral portions in said dielectric plate.
Claim 3
Dependent Claim 34 words
An apparatus according to claim 1, wherein said central conductor penetrates said dielectric plate and is connected to said first conductive plate, and said outer conductive pipe is connected to said second conductive plate.
Claim 4
Dependent Claim 50 words
An apparatus according to claim 1, wherein said microwave inlet ports are located opposite to said support surface, and a distance from said support surface or a surface of said substrate to said microwave inlet ports is set to be an integer multiple of 1/2 a wavelength of the microwave.
Claim 5
Dependent Claim 16 words
An apparatus according to claim 1, wherein said dielectric plate essentially consists of a ceramic material.
Claim 6
Dependent Claim 23 words
An apparatus according to claim 2, wherein said coaxial line is connected to a microwave generator through a coaxial converter and a waveguide.
Claim 7
Dependent Claim 18 words
An apparatus according to claim 5, wherein a tuner for adjusting impedance matching is arranged in said waveguide.
Claim 8
Dependent Claim 17 words
An apparatus according to claim 3, wherein said support surface is formed to support a semiconductor wafer.
Claim 9
Dependent Claim 16 words
An apparatus according to claim 7, wherein said gas supply means comprises etching gas supply means.
Claim 10
Dependent Claim 27 words
An apparatus according to claim 8, further comprising means for applying an RF bias potential to said support surface, said support surface being constituted by a conductor.
Claim 11
Dependent Claim 21 words
An apparatus according to claim 8, wherein a coolant path for cooling said support surface is arranged in said support table.
Claim 12
Dependent Claim 24 words
An apparatus according to claim 9, wherein electrostatic chuck means for fixing the wafer on said support surface is arranged in said support table.
Claim 13
Dependent Claim 16 words
An apparatus according to claim 7, further comprising lift means for vertically moving said support table.
Claim 14
Dependent Claim 91 words
An apparatus according to claim 12, further comprising means for applying an RF bias potential to said support surface, said support surface being constituted by a conductor, a coolant path, formed in said support table, for cooling said support surface, and electrostatic chuck means for fixing the wafer on said support surface, and wherein said lift means comprises a hollow lifting rod extending through said chamber, said bias potential applying means, said coolant path, and said electrostatic chuck means communicating with associated members outside said chamber through said hollow lifting rod.
Claim 15
Dependent Claim 19 words
An apparatus according to claim 1, wherein said support table is conductive and is electrically isolated from the chamber.
Claim 16
Dependent Claim 19 words
An apparatus according to claim 1, wherein said slits comprise T-shaped slits and are arranged along a spiral line.

References Cited (Backward Citations)

US4672346A Cited
JPS63288023A Cited
JPS642322A Cited
JPS6481321A Cited
US5034086A Cited
JPH01236628A Cited
JPH0294628A Cited
US4985109A Cited
US5013401A Cited
US5078851A Cited
US5181986A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-08-29 1998-02-28 1998-08-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-08-29 2002-02-28 2002-08-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-08-29 2006-02-28 2006-08-30 $7700.00 Window Closed / Lapsed

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