US4110775A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Schottky diode with voltage limiting guard band
Assignee: Individual
•
Filing: 1977-11-25
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Granted: 1978-08-29
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Expires: 1997-11-25
Abstract
Abstract A metal-semiconductor diode which includes an integral voltage clamping guard band. The guard band is defined by a p-type region disposed in an n-type epitaxial layer which layer contacts the anode barrier metal. The guard band in addition to reducing edge leakage, limits the reverse voltage on the metal-semiconductor barrier to less than its avalanche breakdown voltage. This provides transient voltage protection for the diode.
Inventors
- 👤 Thomas A. Festa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:12
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/102; H10D62/103; H10D62/105; H10D62/106; H10D8/00; H10D8/60
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
114 words
A metal-semiconductor diode comprising: a semiconductor body of a first conductivity type including a silicon substrate having an epitaxial layer disposed thereon; a metal layer in contact with said epitaxial layer, said metal layer and epitaxial layer forming a metal-semiconductor barrier; and integral circuit protection means for protecting said metal-semiconductor barrier from large reverse potentials by voltage clamping said barrier to a predetermined potential, said circuit protection means comprising a region of a second conductivity type disposed in said epitaxial layer in contact with said metal layer, said region and epitaxial layer forming a junction, the breakdown voltage of said junction being approximately equal to or lower than the breakdown voltage of said barrier.
Claim 2
Dependent Claim
114 words
A metal-semiconductor diode comprising: a semiconductor body of a first conductivity type including a silicon substrate having an epitaxial layer disposed thereon; a metal layer in contact with said epitaxial layer, said metal layer and epitaxial layer forming a metal-semiconductor barrier; and integral circuit protection means for protecting said metal-semiconductor barrier from large reverse potentials by voltage clamping said barrier to a predetermined potential, said circuit protection means comprising a region of a second conductivity type disposed in said epitaxial layer in contact with said metal layer, said region and epitaxial layer forming a junction, the breakdown voltage of said junction being approximately equal to or lower than the breakdown voltage of said barrier.
Claim 3
Dependent Claim
30 words
The diode according to claim 1, wherein said region is p-type, said substrate is n-type and said epitaxial layer is n-type and doped to a lesser concentration than said substrate.
Claim 4
Dependent Claim
26 words
The diode according to claim 2, wherein said region is diffused with boron, said metal layer is tungsten and said epitaxial layer is doped with phosphorus.
References Cited (Backward Citations)
US4025802A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-08-28 | 1982-02-27 | 1982-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-08-28 | 1986-02-27 | 1986-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-08-28 | 1990-02-27 | 1990-08-29 | $7700.00 | Window Closed / Lapsed |