US3641403A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thyristor with degenerate semiconductive region
Assignee: Mitsubishi Electric Corp
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Filing: 1970-05-25
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Granted: 1972-02-08
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Expires: 1990-05-25
Abstract
Abstract There is disclosed a thyristor provided with junctions formed such that predetermined portions of a cathode emitter junction and the adjacent portions of both regions forming that junction are highly doped to be degenerated thereby to introduce a multiplicity of centers of recombination. The thyristor is free from the disadvantages of the conventional shorted emitter-type thyristors and still retaining their advantages.
Inventors
- 👤 Josuke Nakata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:39
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/13; H10D62/141; H10D62/148; H10D62/17; H10D62/192; H10D62/206
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
108 words
A thyristor device comprising, a wafer of semiconductive material including four semiconductive layers of alternate conductivity, a PN-junction formed between the outermost one of said four semiconductive layers providing an emitter region and the adjacent layer providing a base region, at least one degenerate PN-junction forming a part of the first-mentioned PNjunction, and having an ohmic characteristic predominantly dependent upon recombination current at lower levels of current in the order of leakage current and said characteristic predominantly dependent upon diffusion current at higher levels of current in the conductive state, and a gate electrode disposed on said base region to control the current-to-voltage characteristic of the thyristor device.
Claim 2
Dependent Claim
108 words
A thyristor device comprising, a wafer of semiconductive material including four semiconductive layers of alternate conductivity, a PN-junction formed between the outermost one of said four semiconductive layers providing an emitter region and the adjacent layer providing a base region, at least one degenerate PN-junction forming a part of the first-mentioned PNjunction, and having an ohmic characteristic predominantly dependent upon recombination current at lower levels of current in the order of leakage current and said characteristic predominantly dependent upon diffusion current at higher levels of current in the conductive state, and a gate electrode disposed on said base region to control the current-to-voltage characteristic of the thyristor device.
Claim 3
Dependent Claim
31 words
A thyristor device as claimed in claim 1, wherein said base region has an impurity concentration decreasing with an increase in distance from the emitter region adjacent to said base region.
Claim 4
Dependent Claim
47 words
A thyristor device as claimed in claim 1, wherein said base region has an impurity concentration decreasing with an increase in distance from an emitter region adjacent to said base region, said base region having a maximum impurity concentration of 1 X 1017 atoms per cubic centimeter.
Claim 5
Dependent Claim
20 words
A thyristor device as claimed in claim 1, wherein a plurality of the last-mentioned PN-junctions are disposed in spaced relationship.
Claim 6
Dependent Claim
17 words
A thyristor device as claimed in claim 1, wherein the last-mentioned PN-junction has a circular cross section.
Claim 7
Dependent Claim
31 words
A thyristor device as claimed in claim 1, wherein a plurality of the last-mentioned PN-junctions are substantially uniformly distributed in spaced relationship on an interface of said emitter and base regions.
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) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |