Patent US4663559A successfully refreshed from Google Patents.
US4663559A
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Field emission device
Assignee: Individual
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Filing: 1985-11-15
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Granted: 1987-05-05
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Expires: 2005-11-15
Abstract
Abstract A device is disclosed which produces high current, low noise, low lateral energy, stochastic electron emission from a multiplicity of insulative particles subjected to a field. The insulative particles are in and of a surface thickness comprised of a random mixture of insulative and conductive particles in ohmic contact. Emission is achieved at applied potentials of about 5 volts which produce a field sufficient to emit electron currents of nanoamperes to milliamperes. Single devices or arrays of devices may be batch fabricated. Each device has an imtegral, implicity self-aligned electron optic system comprising means for modulating, focusing and deflecting the formed current beam, and means shielding the device from ambient magnetic fields.
Inventors
- 👤 Alton O. Christensen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:13
CPC Classifications
H; H01; H01J; H01J3/00; H01J3/02; H01J3/021; H01J1/00; H01J1/02; H01J1/30; H01J1/304; H01J1/3042; H01J2201/00; H01J2201/30; H01J2201/304; H01J2201/30403; H01J2201/319
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
62 words
A field emission device wherein emission is obtained from particles of insulative material under the influence of a field, and wherein a barrier to emission is the conduction band width and is less than about 1 ev, and wherein the insulative particles are a component of a cermet of randomly arranged conductive and insulative particles, and ohmic contact exists between the particles.
Claim 2
Dependent Claim
62 words
A field emission device wherein emission is obtained from particles of insulative material under the influence of a field, and wherein a barrier to emission is the conduction band width and is less than about 1 ev, and wherein the insulative particles are a component of a cermet of randomly arranged conductive and insulative particles, and ohmic contact exists between the particles.
Claim 3
Dependent Claim
17 words
The device of claim 1 wherein the insulative particles have an average diameter of about 3.5 nanometers.
Claim 4
Dependent Claim
36 words
The device of claim 1 wherein electrons in the insulative particles have at least the energy of the Fermi level of the conductive material, and energy imparted by an applied field to the electrons initiates emission.
Claim 5
Dependent Claim
31 words
The device of claim 3 wherein said field is sufficient to cause electron traps in said insulative particles to be overfilled, and all electrons flow in the insulative material conduction band.
Claim 6
Dependent Claim
22 words
The field emission device of claim 3 wherein said cermet comprises randomly arranged conductive particles conductively connected to randomly arranged insulative particles.
Claim 7
Dependent Claim
47 words
The field emission device of claim 4 wherein said cermet is formed upon a conductive substrate, and a separate conductor is spaced above and insulated from said substrate and said cermet, and a field is formed by a potential applied between said substrate and said separate conductor.
Claim 8
Dependent Claim
28 words
The field emission device of claim 3 wherein the cermet is formed into pointed structure and wherein the particles at the surface of the point are insulative particles.
Claim 9
Dependent Claim
60 words
The field emission device of claim 7 wherein said pointed structure is centered in an aperture of a conductive electrode, and said cermet is formed upon and conductively connected at a base to a conductive substrate and a potential applied between said substrate and conductive electrode operates on said point and said cermet to emit electron flow from said point.
Claim 10
Dependent Claim
41 words
The field emission device of claim 1 wherein the conductive material is refactory metal, nickel, silver, aluminum, rare earth borides, highly doped silicon or a silicide of refractory metal and having a lesser work function that that of said insulative material.
Claim 11
Dependent Claim
23 words
The field emission device of claim 1 wherein the insulative particles and the conductive particles have a maximum dimension of about 5.0 nanometers.
Claim 12
Dependent Claim
15 words
The field emission device of claim 1 wherein the radius conductive particles are trichromium silicide.
Claim 13
Dependent Claim
32 words
The device of claim 1 wherein the insulative material is Al 2 O 3 , BeO, B 2 O 3 , BN, CaO, MgO, SiO 2 or Si 3 N 4 .
Claim 14
Dependent Claim
36 words
The device of claim 12 wherein the insulative material has minimal affinity for oxygen or other gasses of the same electropolarity prohibiting chemisorption on the emitting particles which would otherwise cause noise or degradation of emission.
Claim 15
Dependent Claim
46 words
The field emission device of claim 6 wherein said potential is less than the ionization potential of gasses or vapors residual within or diffusing within said field preventing abalation by ionized particles of said point and resulting noise modulation of emission and degradation of emission levels.
Claim 16
Dependent Claim
147 words
A field emission device comprising a conductive substrate conductively connected to cermet of insulative and conductive particles of pyramidal or conical shape with a point centered in an aperture of a first conductor, and a potential is applied between said substrate and said first conductor forming a field causing electrons to flow through the cermet in the conduction band of the insulative particles with a barrier to emission of less than about 1 ev, the electron flow to the point of the cermet into vacuum being from insulative particles of the surface of the point, the potential producing the field for emission being less than the ionization potential of gasses or vapors residual within or diffusing within the field to preserve the integrity of the emitting insulative particles, reduce noise and emitted current degradation, and allow operation in the presence of vapors or gasses in the field.
Claim 17
Dependent Claim
147 words
A field emission device comprising a conductive substrate conductively connected to cermet of insulative and conductive particles of pyramidal or conical shape with a point centered in an aperture of a first conductor, and a potential is applied between said substrate and said first conductor forming a field causing electrons to flow through the cermet in the conduction band of the insulative particles with a barrier to emission of less than about 1 ev, the electron flow to the point of the cermet into vacuum being from insulative particles of the surface of the point, the potential producing the field for emission being less than the ionization potential of gasses or vapors residual within or diffusing within the field to preserve the integrity of the emitting insulative particles, reduce noise and emitted current degradation, and allow operation in the presence of vapors or gasses in the field.
Claim 18
Dependent Claim
69 words
The field emission device of claim 15 including two pairs of deflection bars orthogonal to and insulated from each other and from said first conductor, and said bars are centered relative to the emitting point; voltage means applied to one deflection pair; separate voltage means connected to the other deflection pair; and wherein said deflection bars are operative to deflect the emitted electrons and to focus the emitted electrons.
Claim 19
Dependent Claim
20 words
The field emission device of claim 16 wherein the spacing between the deflection bar pairs is less than 1.7 micrometer.
Claim 20
Dependent Claim
25 words
The field emission device of claim 16 wherein the voltage applied by said voltage means is less than the ionization potential of gasses or vapors.
Claim 21
Dependent Claim
42 words
A multiplicity of the field emission devices of claim 15 sharing a common substrate each directed to an assigned area of respective targets, and including integrated circuit control means integrally supported by said common substrate for the multiplicity of field emission devices.
Claim 22
Dependent Claim
22 words
The field emission devices of claim 19 wherein said integrated circuit means operates individual field emitters modulating and deflecting electron emission therefrom.
Claim 23
Dependent Claim
29 words
The field emission device of claim 16, wherein the deflection voltages supplied to the orthogonal deflection bars are controllably offset from a reference potential to focus the electron beam.
Claim 24
Dependent Claim
31 words
The field emission device of claim 15 wherein the emitting surface is multiplicity of insulative particles within a 60° solid angle point and said multiplicity of insulative particles simultaneously emit electrons.
Claim 25
Dependent Claim
20 words
The field emission device of claim 15 formed of trichromium silicide particles in ohmic contact with silica or beryllia particles.
Claim 26
Dependent Claim
20 words
The field emission device of claim 1 formed of trichromium silicide particles in ohmic contact with silica or beryllia particles.
References Cited (Backward Citations)
US2996795A
Cited
US2914402A
Cited
US3232717A
Cited
US3600334A
Cited
US3489554A
Cited
US3753022A
Cited
US4092560A
Cited
US4038216A
Cited
US4131459A
Cited
US4155758A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-05-04 | 1990-11-03 | 1991-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-04 | 1994-11-03 | 1995-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-04 | 1998-11-03 | 1999-05-05 | $7700.00 | Window Closed / Lapsed |