US4040080A
Expired / Lapsed
US
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Semiconductor cold electron emission device
Assignee: Hamamatsu Terebi KK
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Filing: 1976-09-20
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Granted: 1977-08-02
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Expires: 1996-09-20
Abstract
Abstract A semiconductor cold emission device comprising at least two different semiconductors and a junction with a first region having n-type conductivity and a second region which is a p-type conductivity and an indirect transition type material whose effective forbidden bandwidth is smaller than that of the first region and means for applying voltage to the junction to cause electrons injected from the first region to the second region to be emitted from the surface of the second region to the exterior.
Inventors
- 👤 Katsuo Hara
- 👤 Minoru Hagino
- 👤 Tokuzo Sukegawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:01
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/30; H01J1/308; H01J9/00; H01J9/02; H01J9/022
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
214 words
A cold emission semiconductor device comprising a first layer of GaAlP, and of several hundred Angstroms thickness and of n-type conductivity; a second layer of GaAlP of p-type conductivity and of a thickness less than the diffusion length of electrons, and whose effective forbidden band gap is smaller than that of said first layer, said first and said second layers being intimately in contact with each other through epitaxial growth and with substantial lattice match to form a heterojunction, said second layer having a surface opposite said heterojunction with zero or negative electron affinity for emission of electrons, a first electrode connectable to said first layer, and a second electrode connectable to said second layer with the distance between said second electrode and said heterojunction being more than the diffusion length of electrons, and means for applying a potential to said electrodes to bias said heterojunction and cause said first layer to generate electrons which are subsequently injected into said second layer and without substantially any recombination emitted from said surface of said second layer, wherein an insulating or high resistance layer is provided at selected portions toward either side of said junction to enable concentration of electron flow to areas of said junction not effectively convered by said insulating or high resistance layer.
Claim 2
Dependent Claim
214 words
A cold emission semiconductor device comprising a first layer of GaAlP, and of several hundred Angstroms thickness and of n-type conductivity; a second layer of GaAlP of p-type conductivity and of a thickness less than the diffusion length of electrons, and whose effective forbidden band gap is smaller than that of said first layer, said first and said second layers being intimately in contact with each other through epitaxial growth and with substantial lattice match to form a heterojunction, said second layer having a surface opposite said heterojunction with zero or negative electron affinity for emission of electrons, a first electrode connectable to said first layer, and a second electrode connectable to said second layer with the distance between said second electrode and said heterojunction being more than the diffusion length of electrons, and means for applying a potential to said electrodes to bias said heterojunction and cause said first layer to generate electrons which are subsequently injected into said second layer and without substantially any recombination emitted from said surface of said second layer, wherein an insulating or high resistance layer is provided at selected portions toward either side of said junction to enable concentration of electron flow to areas of said junction not effectively convered by said insulating or high resistance layer.
Claim 3
Dependent Claim
19 words
The device of claim 1, wherein said surface opposite said heterojunction is activated by cesium or cesium and oxygen.
Claim 4
Dependent Claim
17 words
The device of claim 1, further comprising means for providing drift electric field to increase transport factor.
Claim 5
Dependent Claim
87 words
The device of claim 1, comprising, in order, an electrode, n-type layer of GaP, n-type layer of Al(x)Ga(1-x)P, wherein x is a positive number less than 1, defining said first region, insulating layer covering selected parts of said layer of Al(x)Ga(1-x)P, p-type layer of GaP defining said second region and covering said insulating layer and the uncovered portion of said Al(x)Ga(1-x)P to form a junction therewith, an electron emissive surface on the opposite side thereof, and ohmic contacts covering selected portions of said p-type layer of GaP.
Claim 6
Dependent Claim
70 words
The device of claim 1, comprising, in order, an electrode, a base, p-type region covering selected parts of said base, n-type layer of Al(x)Ga(1-x)P, wherein x is a positive number less than 1, defining a first region, p-type layer forming a junctionwith said first region and defining a second regin with an electron emissive surface on the opposite side thereof, and ohmic contacts at selected portions of said p-type layer.
Claim 7
Dependent Claim
111 words
The deive of claim 1, comprising, in order, an electrode, an insulating layer covering selected portions of said electrode, an n-type layer of GaP covering said insulating layer and the uncovered portions of said electrode, an n-type layer of Al(x)Ga(1-x)P, wherein x is a positive number less than 1, defining said first region, a p-type layer of GaP defining said second region having a surface for electron emission directly opposite said uncovered portion, a p-type layer of Al(z)Ga(1-z)P, directly opposited said covered portion, wherein z is a positive number less than 1, a p-type layer of GaP on said p-type Al(z)Ga(1-z)P layer, and ohmic contacts on said p-type layer of GaP.
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) | 1980-08-01 | 1981-01-31 | 1981-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-01 | 1985-01-31 | 1985-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-01 | 1989-01-31 | 1989-08-02 | $7700.00 | Window Closed / Lapsed |