US4578614A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultra-fast field emitter array vacuum integrated circuit switching device
Assignee: United States Department of the Navy
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Filing: 1982-07-23
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Granted: 1986-03-25
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Expires: 2002-07-23
Abstract
Abstract A field-emitter switching device wherein a positive pulse is applied to a te (which is held at a bias potential V 1 just below turn-on). A collector is held at a potential higher than the gate in order to collect emitted electrons from a field emitter source. As the voltage is applied to the gate, electrons are emitted immediately from the source and travel to the most positive potential at the collector. Because of the field emitter geometry, such electron transport is extremely fast. The ultra-fast switching speed is attained because the electrons reach near-maximum velocity within a few field tip diameters of the source.
Inventors
- 👤 Henry F. Gray
- 👤 Richard F. Greene
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:04
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/54; H03K17/545; H01; H01J; H01J1/00; H01J1/02; H01J1/30; H01J1/304; H01J1/3042
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
149 words
An ultra-fast microminiature planar switching device comprising: an electron-emissive substrate; an insulating layer formed over a surface of the substrate; a field-emission cathode comprised by an opening formed in the insulating layer exposing a part of the underlying substrate, with the central region of the exposed underlying material forming a raised emitting tip integral with the underlying substrate; a gate electrode for control of electron extraction from the field-emission cathode comprised by a first metallization located on the insulating layer and adjacent to the opening; a collector electrode for collection of substantially all electron emission from the field-emission cathode comprised by a second metallization located on the insulating layer and separated from the first metallization; and means for supplying an input signal to the gate to cause emission and travel of electrons from the field emission cathode to the collector and for extracting an output signal from the collector.
Claim 2
Dependent Claim
149 words
An ultra-fast microminiature planar switching device comprising: an electron-emissive substrate; an insulating layer formed over a surface of the substrate; a field-emission cathode comprised by an opening formed in the insulating layer exposing a part of the underlying substrate, with the central region of the exposed underlying material forming a raised emitting tip integral with the underlying substrate; a gate electrode for control of electron extraction from the field-emission cathode comprised by a first metallization located on the insulating layer and adjacent to the opening; a collector electrode for collection of substantially all electron emission from the field-emission cathode comprised by a second metallization located on the insulating layer and separated from the first metallization; and means for supplying an input signal to the gate to cause emission and travel of electrons from the field emission cathode to the collector and for extracting an output signal from the collector.
Claim 3
Dependent Claim
23 words
The switching device recited in claim 1 wherein: the emitting tip is point-like; and the first and second metallizations are concentric ring-like structures.
Claim 4
Dependent Claim
13 words
The switching device recited in claim 1 wherein: the emitting tip is ridge-like.
Claim 5
Dependent Claim
155 words
The switching device recited in claim 1 wherein the signal supplying-and-extracting means includes: means for connecting a source of gate bias voltage V 1 between the gate and the substrate; means for connecting a source of collector bias voltage V 2 between the collector and the substrate, wherein the gate bias voltage V 1 is set equal to the cut-off voltage for emission and travel of electrons from the cathode to the collector, and the collector bias voltage V 2 is higher than the gate bias voltage V 1 ; an input coupling capacitor connected to the gate for applying the input signal to increase the potential difference of the gate with respect to the substrate and cause emission and travel of the electrons from the cathode to the collector: an output coupling capacitor connected to the collector; and a resistor connected between the output coupling capacitor and the substrate for developing an output signal.
Claim 6
Dependent Claim
17 words
The switching device recited in claim 1 wherein: the field emission cathode is formed by orientation-dependent etching.
Claim 7
Dependent Claim
14 words
The switching device recited in claim 1 wherein; the substrate consists essentially of silicon.
Claim 8
Dependent Claim
33 words
The switching device recited in claim 1 wherein: the insulating layer is a material selected from the group consisting of SiO 2 , Al 2 O 3 and Si 3 N 4 .
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-03-24 | 1989-09-23 | 1990-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-24 | 1993-09-23 | 1994-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-24 | 1997-09-23 | 1998-03-25 | $7700.00 | Window Closed / Lapsed |