Patent US4559100A successfully refreshed from Google Patents.
US4559100A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave plasma etching apparatus
Assignee: Hitachi Ltd
•
Filing: 1984-12-20
•
Granted: 1985-12-17
•
Expires: 2004-12-20
Abstract
Abstract A microwave plasma etching apparatus comprises: a discharge tube into which a discharge gas is supplied and which forms a discharge region; means for generating a magnetic field in the discharge region; means for bringing a microwave into the discharge region; and a stage for holding a material. In the present invention, the sample exists in the discharge region. On one hand, an area of a passage for draining particles to the outside from the discharge region is 5/16 or less of an area of the discharge region. For this purpose, for example, a diameter of the sample stage is 3/4 or more of a diameter of the discharge region.
Inventors
- 👤 Ken Ninomiya
- 👤 Shigeru Nishimatsu
- 👤 Keizo Suzuki
- 👤 Sadayuki Okudaira
- 👤 Yoshifumi Ogawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:05
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32431; H01J37/32623; H01J37/32009; H01J37/32192; H01J37/3266
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
25 words
A microwave plasma etching apparatus using a microwave discharge with a magnetic field, in which a material to be etched exists in a discharge region.
Claim 2
Dependent Claim
25 words
A microwave plasma etching apparatus using a microwave discharge with a magnetic field, in which a material to be etched exists in a discharge region.
Claim 3
Dependent Claim
32 words
An apparatus according to claim 1, wherein the cross sectional area of a passage to drain particles from said discharge region is 5/16 or less of the area of said discharge region.
Claim 4
Dependent Claim
80 words
An apparatus according to claim 2, wherein a sample stage for supporting said sample is provided and at least one of a diameter of said sample stage and a diameter of a circular cover attached to said sample stage through an insulative material is 3/4 or more of an inner diameter of said discharge region within a range such that said sample stage or said circular cover does not come into contact with an inner wall of said discharge region.
Claim 5
Dependent Claim
45 words
An apparatus according to claim 2, wherein said sample is placed at a position which is 300 mm or less in the direction of propagation of said microwave from a point of the maximum magnetic flux density on a central axis of said discharge region.
Claim 6
Dependent Claim
27 words
An apparatus according to claim 3, wherein a voltage is independently applied from an external power source to said material or to said material and said stage.
Claim 7
Dependent Claim
13 words
An apparatus according to claim 2, further comprising means for cooling said material.
Claim 8
Dependent Claim
52 words
A microwave plasma etching apparatus comprising: a discharge tube into which a discharge gas is supplied and which forms a discharge region; means for generating a magnetic field in said discharge region; means for bringing a microwave into said discharge region; and a stage for holding a material in said discharge region.
Claim 9
Dependent Claim
52 words
A microwave plasma etching apparatus comprising: a discharge tube into which a discharge gas is supplied and which forms a discharge region; means for generating a magnetic field in said discharge region; means for bringing a microwave into said discharge region; and a stage for holding a material in said discharge region.
Claim 10
Dependent Claim
23 words
A device according to claim 7, wherein a diameter of said stage is 3/4 or more of the diameter of said discharge region.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-16 | 1989-06-17 | 1989-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-16 | 1993-06-17 | 1993-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-16 | 1997-06-17 | 1997-12-17 | $7700.00 | Window Closed / Lapsed |