← Back to Patent Explorer
US4430138A Expired / Lapsed US ⏱️ 0.0 years remaining

Microwave plasma etching apparatus having fan-shaped discharge

Assignee: Hitachi Ltd
•
Filing: 1980-04-07
•
Granted: 1984-02-07
•
Expires: 2000-04-07
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In a microwave plasma etching apparatus wherein the surface of a sample is exposed to a plasma generated by microwave discharge, thereby to subject the sample surface to an etching processing; the sample is transported while revolving along a circular orbit in a plasma exposure region, and the section of the plasma exposure region is put into the shape of a fan whose pivot coincides with the central point of the circuit orbit, whereby the enhancement of the etching processing capability and the uniformity of the etching speed are achieved.

Inventors

  • 👤 Keizo Suzuki
  • 👤 Sadayuki Okudaira
  • 👤 Shigeru Nishimatsu
  • 👤 Ichiro Kanomata

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 19:31
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0402; H10P72/0418; H10P72/0421; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32192; H05; H05H; H05H1/00; H05H1/24; H05H1/26; H05H1/30; H01J2237/00; H01J2237/32; H01J2237/33; H01J2237/334; H01J2237/3343

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 90 words
A microwave plasma etching apparatus for exposing a sample to a microwave discharge plasma, comprising: a discharge tube which has an opening portion confronting the surface of said sample, said opening portion being formed into the shape of a fan; means to generate a microwave discharge plasma in said discharge tube; and means for moving said sample along a circular path whose center coincides with the pivot of said fan, wherein said discharge tube is gradually tapered from a portion having a circular sectional shape towards said fan-shaped opening portion.
Claim 2
Dependent Claim 90 words
A microwave plasma etching apparatus for exposing a sample to a microwave discharge plasma, comprising: a discharge tube which has an opening portion confronting the surface of said sample, said opening portion being formed into the shape of a fan; means to generate a microwave discharge plasma in said discharge tube; and means for moving said sample along a circular path whose center coincides with the pivot of said fan, wherein said discharge tube is gradually tapered from a portion having a circular sectional shape towards said fan-shaped opening portion.

References Cited (Backward Citations)

US2160981A Cited
US2432950A Cited
US2997979A Cited
US3442572A Cited
US3636916A Cited
US3502051A Cited
US3561993A Cited
US3677924A Cited
US3664948A Cited
US3827966A Cited
US4094722A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-02-06 1987-08-08 1988-02-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-02-06 1991-08-08 1992-02-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-02-06 1995-08-08 1996-02-07 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag