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US4877509A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor wafer treating apparatus utilizing a plasma

Assignee: Mitsubishi Electric Corp
•
Filing: 1988-11-10
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Granted: 1989-10-31
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Expires: 2008-11-10
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Abstract

Abstract An apparatus for treating semiconductor wafers utilizing a plasma generated by electron cyclotron resonance (ECR) is disclosed in which a microwave is supplied to a plasma generating chamber via a rectangular waveguide, a rectangular-to-circular microwave converter, and a circular polarization converter. The polarization converter may comprise a phase shift plate of a dielectric material or an electrically conductive material disposed in a circular waveguide in the form of a metallic cylinder. The polarization converter transforms a circular TE 11 mode microwave supplied from the rectangular-to-circular microwave converter to a circularly polarized one by rotating the direction of the electric field of the microwave in the TE 11 mode one complete turn in one period of the microwave. Thus, the electric field strength of the microwave supplied to the plasma generating chamber is averaged over the time along the circumferential direction in the plasma generating chamber to make the density of plasma generation therein spatially uniform. The spatially uniformly distributed plasma generated in the plasma generating chamber is conveyed to the wafer in the wafer treating chamber to effect a treatment of the wafer.

Inventors

  • 👤 Toshiaki Ogawa
  • 👤 Nobuo Fujiwara
  • 👤 Kenji Kawai
  • 👤 Teruo Shibano
  • 👤 Hiroshi Morita
  • 👤 Kyusaku Nishioka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 20:35
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32192; H01J37/32293; C; C23; C23C; C23C16/00; C23C16/44; C23C16/50; C23C16/511; H01J37/32431; H01J37/3266; H01J37/32678

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 281 words
An apparatus for treating semiconductor wafers utilizing a plasma generated by electron cyclotron resonance comprising: a first chamber accommodating means for supporting a semiconductor wafer; a second chamber disposed adjacent to and in communication with said first chamber; gas supplying means for supplying a gas to said second chamber; a microwave source; waveguide means operatively coupled to said microwave source for guiding microwave energy generated by said microwave source toward said second chamber, said waveguide means comprising converter means for converting microwaves propagating in a rectangular mode into microwaves propagating in a circular mode; circular polarization means interposed between said waveguide means and said second chamber for rotating the direction of oscillation of an electric field of microwves in a circular TE 11 ) mode supplied from said waveguide means one complete turn in a circumferential direction in one period of the microwave, thereby converting the microwave in a circular mode into chamber polarized microwaves, said circular polarization means comprising means for supplying the circularly polarized microwaves to said second chamber; and electromagent means surrounding at least said second chamber for forming a magnetic field in said first and second chambers, said electromagnet means forming in said second chamber a magnetic field of a magnetic flux density sufficient to produce electron cyclotron resonance in cooperation with the microwave energy supplied from said circular polarization means, thereby generating a plasma of said gas in said second chamber, said electromagnet means forming in said first chamber a magnetic field diverging in a direction from said second chamber to said support means, thereby causing a plasma generated in said second chamber to be transported to said semiconductor wafer supported by said means for supporting.
Claim 2
Independent Claim 281 words
An apparatus for treating semiconductor wafers utilizing a plasma generated by electron cyclotron resonance comprising: a first chamber accommodating means for supporting a semiconductor wafer; a second chamber disposed adjacent to and in communication with said first chamber; gas supplying means for supplying a gas to said second chamber; a microwave source; waveguide means operatively coupled to said microwave source for guiding microwave energy generated by said microwave source toward said second chamber, said waveguide means comprising converter means for converting microwaves propagating in a rectangular mode into microwaves propagating in a circular mode; circular polarization means interposed between said waveguide means and said second chamber for rotating the direction of oscillation of an electric field of microwves in a circular TE 11 ) mode supplied from said waveguide means one complete turn in a circumferential direction in one period of the microwave, thereby converting the microwave in a circular mode into chamber polarized microwaves, said circular polarization means comprising means for supplying the circularly polarized microwaves to said second chamber; and electromagent means surrounding at least said second chamber for forming a magnetic field in said first and second chambers, said electromagnet means forming in said second chamber a magnetic field of a magnetic flux density sufficient to produce electron cyclotron resonance in cooperation with the microwave energy supplied from said circular polarization means, thereby generating a plasma of said gas in said second chamber, said electromagnet means forming in said first chamber a magnetic field diverging in a direction from said second chamber to said support means, thereby causing a plasma generated in said second chamber to be transported to said semiconductor wafer supported by said means for supporting.
Claim 3
Dependent Claim 38 words
An apparatus for treating semiconductor wafers as claimed in claim 1 wherein said circular polarization means comprises a hollow cylinder and a phase shift plate disposed in said cylinder to extend in an axial direction of the cylinder.
Claim 4
Dependent Claim 33 words
An apparatus for treating semiconductor wafers as claimed in claim 2 wherein said waveguide means further comprises a waveguide of a rectangular cross section connected between said microwave source and said converter means.
Claim 5
Dependent Claim 39 words
An apparatus for treating semiconductor wafers as claimed in claim 2 wherein said second chamber is enclosed by a dome of quartz projecting into a cylindrical space formed by an electrically conductive hollow cylinder surrounded by said electronmagent means.
Claim 6
Dependent Claim 33 words
An apparatus for treating semiconductor wafers as claimed in claim 1 wherein said waveguide means further comprises a waveguide of a rectangular cross section connected between said microwave source and said converter means.
Claim 7
Dependent Claim 39 words
An apparatus for treating semiconductor wafers as claimed in claim 1 wherein said second chamber is enclosed by a dome of quartz projecting into a cylindrical space formed by an electrically conductive hollow cylinder surrounded by said electromagent means.
Claim 8
Dependent Claim 25 words
An apparatus for treating semiconductor wafers as claimed in claim 6 further comprising a voltage source biasing said support means for supporting a semiconductor wafer.
Claim 9
Dependent Claim 58 words
An apparatus for treating semiconductor wafers as claimed in claim 1 wherein said waveguide means includes means for converting microwaves propagating in a rectangular TE 10 mode into microwaves propagating in a circular TE 11 mode and said circular polarization means includes a means for converting microwaves propagating in a circular TE 11 mode into circularly polarized microwaves.

References Cited (Backward Citations)

US4507588A Cited
US4611121A Cited
US4630566A Cited
US4581100A Cited
US4757237A Cited
US4776918A Cited
US4778561A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-10-30 1993-05-01 1993-10-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-10-30 1997-05-01 1997-10-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-10-30 2001-05-01 2001-10-31 $7700.00 Window Closed / Lapsed

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