Patent US5646474A successfully refreshed from Google Patents.
US5646474A
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Boron nitride cold cathode
Assignee: Wayne State University
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Filing: 1995-03-27
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Granted: 1997-07-08
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Expires: 2015-03-27
Abstract
Abstract A cold cathode is formed of n-type boron nitride. The cathode may include a layer of diamond underlying the boron nitride. The cathodes are made by laser ablation or by sputtering. Electronic devices utilizing the boron nitride cathodes are also described.
Inventors
- 👤 Roger W. Pryor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:38
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/30; C; C23; C23C; C23C14/00; C23C14/06; C23C14/0641; C23C14/0647; C23C14/22; C23C14/24; C23C14/28
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
62 words
A cathode-containing device in which a cathode emits electrons, comprising: a body defining a vacuum space; a cathode formed of boron nitride, said boron nitride being doped n-type; and an electrode associated with said boron nitride cathode, wherein a surface of said boron nitride cathode contacts said vacuum such that electrons are emitted from said boron nitride cathode into said vacuum space.
Claim 2
Dependent Claim
62 words
A cathode-containing device in which a cathode emits electrons, comprising: a body defining a vacuum space; a cathode formed of boron nitride, said boron nitride being doped n-type; and an electrode associated with said boron nitride cathode, wherein a surface of said boron nitride cathode contacts said vacuum such that electrons are emitted from said boron nitride cathode into said vacuum space.
Claim 3
Dependent Claim
32 words
The cathode-containing device recited in claim 1, wherein said boron nitride is selected from the group consisting of amorphous boron nitride, polycrystalline boron nitride and single crystal boron nitride and combinations thereof.
Claim 4
Dependent Claim
15 words
The cathode-containing device recited in claim 2, wherein said boron nitride is polycrystalline boron nitride.
Claim 5
Dependent Claim
27 words
The cathode-containing device recited in claim 1, wherein said boron nitride is doped n-type with a dopant selected from the group consisting of carbon, lithium, and sulfur.
Claim 6
Dependent Claim
33 words
The cathode-containing device recited in claim 4, wherein said boron nitride is doped with an n-type dopant to a concentration of from about 10 16 to about 10 22 per cm 3 .
Claim 7
Dependent Claim
24 words
The cathode-containing device recited in claim 1, wherein said boron nitride cathode includes a layer of boron nitride disposed on a layer of diamond.
Claim 8
Dependent Claim
13 words
The cathode-containing device recited in claim 6, wherein said diamond is n-type diamond.
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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) | 2000-07-07 | 2001-01-06 | 2001-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-07-07 | 2005-01-06 | 2005-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-07-07 | 2009-01-06 | 2009-07-08 | $7700.00 | Window Closed / Lapsed |