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US5300853A
Expired / Lapsed
US
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Field-emission type switching device
Assignee: Panasonic Holdings Corp
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Filing: 1993-01-06
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Granted: 1994-04-05
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Expires: 2013-01-06
Abstract
Abstract A field-emission type switching device includes a substrate formed with a recess having a straight edge and serrated edge opposite to the straight edge. A gate electrode is formed at the bottom of the recess. An emitter electrode is provided over the substrate and formed with a serrated edge which is slightly off alignment with the serrate edge of the recess so as to provide an emitter overhanging portion overhanging the recess. Similarly, a collector electrode is provided over the substrate and formed with a straight edge which is slightly off alignment with the straight edge of the recess so as to provide a collector overhanging portion overhanging the recess. The emitter and collector electrodes are disposed in one plane and the gate electrode is disposed in another plane below the one plane.
Inventors
- 👤 Masanori Watanabe
- 👤 Hiroyuki Kado
- 👤 Takao Chikamura
- 👤 Nobuyuki Yoshiike
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:03
CPC Classifications
H; H01; H01J; H01J21/00; H01J21/02; H01J21/06; H01J21/10; H01J21/105; H01J3/00; H01J3/02; H01J3/021; H01J3/022
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
144 words
A field-emission type switching device comprising: an insulation layer disposed on a semiconductor substrate layer; an electrically conductive layer disposed over said insulation layer; an emitter electrode formed in said electrically conductive layer and having a serrated edge having at least one tip and a collector electrode, formed in said electrically conductive layer, and having a straight edge; said insulation layer having a recess formed therein such that an emitter overhanging portion is formed overhanging said recess and a collector overhanging portion is formed overhanging said recess; a gate electrode formed at the bottom of said recess; wherein said overhanging portions have tapered edges and wherein the at least one tip of the serrated edge of the emitter electrode has a thickness within a range of 0.02-0.04 micrometers and wherein the point of contact of the emitter electrode with the insulation layer is thick.
Claim 2
Dependent Claim
144 words
A field-emission type switching device comprising: an insulation layer disposed on a semiconductor substrate layer; an electrically conductive layer disposed over said insulation layer; an emitter electrode formed in said electrically conductive layer and having a serrated edge having at least one tip and a collector electrode, formed in said electrically conductive layer, and having a straight edge; said insulation layer having a recess formed therein such that an emitter overhanging portion is formed overhanging said recess and a collector overhanging portion is formed overhanging said recess; a gate electrode formed at the bottom of said recess; wherein said overhanging portions have tapered edges and wherein the at least one tip of the serrated edge of the emitter electrode has a thickness within a range of 0.02-0.04 micrometers and wherein the point of contact of the emitter electrode with the insulation layer is thick.
Claim 3
Dependent Claim
18 words
A switching device as recited in claim 1, wherein said gate electrode is formed by an ion-injection process.
Claim 4
Dependent Claim
18 words
A switching device as recited in claim 1, wherein said gate electrode is formed of a metallic film.
Claim 5
Dependent Claim
28 words
A switching device as recited in claim 1, wherein said tapered edge of said emitter overhanging portion has a radius of curvature in the range of 0.5-1.0 micrometers.
Claim 6
Dependent Claim
25 words
A switching device as recited in claim 1, wherein a distance between said emitter electrode and collector electrode is in the range of 1-3 micrometers.
Claim 7
Dependent Claim
18 words
A switching device as recited in claim 1, wherein said insulation layer has a thickness of 0.3-0.6 micrometers.
Claim 8
Dependent Claim
36 words
A switching device as recited in claim 1, wherein said collector electrode and said gate electrode are spaced apart by a distance which is greater than the spacing between said emitter electrode and said gate electrode.
Claim 9
Dependent Claim
28 words
A switching device as recited in claim 1, wherein said emitter electrode and said gate electrode are spaced apart by a distance in the range of 0.5-1.0 micrometers.
Claim 10
Dependent Claim
28 words
A switching device as recited in claim 1, wherein said collector electrode and said gate electrode are spaced apart by a distance in the range of 1-2 micrometers.
Claim 11
Dependent Claim
30 words
A switching device as recited in claim 1, wherein said emitter electrode and said gate electrode are at different heights with a height difference in the range of 0.5-1.0 micrometers.
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) | 1997-04-04 | 1997-10-04 | 1998-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-04-04 | 2001-10-04 | 2002-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-04-04 | 2005-10-04 | 2006-04-05 | $7700.00 | Window Closed / Lapsed |