US3766449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistors
Assignee: Ferranti International PLC
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Filing: 1972-03-27
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Granted: 1973-10-16
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Expires: 1992-03-27
Abstract
Abstract A transistor having a high inverse gain value, and especially a multi-emitter transistor, is provided both with an additional feedback emitter directly connected to the base and positioned adjacent to the base contact, together with a base resistor portion between the region of the base having the base contact and the additional emitter and the region of the base in which each other emitter is formed.
Inventors
- 👤 J Bruchez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:20
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/60; H10D84/611; H10D84/613; H10D84/615; H10D62/00; H10D62/10; H10D62/13; H10D62/133; H10D62/135
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
71 words
A transistor having a high inverse current gain value, comprising a collector, a base comprising a first region, a second region and a resistor portion connecting said first region to said second region, a base contact to the second region, at least one emitter within the first region, and an additional emitter within said second region, said additional emitter being adjacent to the base contact and directly connected to the base.
Claim 2
Dependent Claim
71 words
A transistor having a high inverse current gain value, comprising a collector, a base comprising a first region, a second region and a resistor portion connecting said first region to said second region, a base contact to the second region, at least one emitter within the first region, and an additional emitter within said second region, said additional emitter being adjacent to the base contact and directly connected to the base.
Claim 3
Dependent Claim
19 words
A transistor as claimed in claim 1 having a plurality of emitters within the first region of the base.
Claim 4
Dependent Claim
81 words
A transistor as claimed in claim 1 which is formed in a semiconductor body comprising an epitaxial layer of one conductivity type on a semiconductor substrate of the same conductivity type, the transistor having a collector of the opposite conductivity type comprising both a heavily doped isolation barrier for the transistor and a heavily doped buried layer at the interface between the epitaxial layer and the substrate, the isolation barrier extending through the epitaxial layer into contact with the buried layer.
Claim 5
Dependent Claim
37 words
A transistor as claimed in claim 1 in which the base contact spans a part of the P-N junction between the base and the additional emitter forming a common contact to the base and the additional emitter.
Claim 6
Dependent Claim
46 words
A transistor as claimed in claim 1 in which the cross-sectional area of the base transverse to the direction of movement of charge carrIers between the base contact and each emitter within the first region is smaller for the resistor portion than for the first region.
Claim 7
Dependent Claim
24 words
A transistor as claimed in claim 1 in which the base resistor portion is between the additional emitter and the collector of the transistor.
Claim 8
Dependent Claim
24 words
A transistor as claimed in claim 6 having the additional emitter encircling a part of the base to which the base contact is provided.
Claim 9
Dependent Claim
46 words
A transistor as claimed in claim 6 in which the cross-sectional area of the base transverse to the direction of movement of charge carriers between the base contact and each emitter within the first region is smaller for the resistor portion than for the first region.
Claim 10
Dependent Claim
37 words
A transistor as claimed in claim 6 in which the base contact spans a part of the P-N junction between the base and the additional emitter forming a common contact to the base and the additional emitter.
Claim 11
Dependent Claim
123 words
A transistor formed in an epitaxial layer of one conductivity type on a substrate of the same conductivity type and having a high inverse current gain value comprising a collector of the opposite conductivity type comprising both a heavily doped isolation barrier and a heavily doped buried layer, said isolation barrier extending through the epitaxial layer into contact with the buried layer, a base comprising a first region, a second region and a resistor portion connecting said first region to said second region, at least one emitter within said first region, a feedback emitter within said second region, and a base contact spanning the junction between the base and the feedback emitter forming a common contact to the base and said feedback emitter.
Claim 12
Dependent Claim
123 words
A transistor formed in an epitaxial layer of one conductivity type on a substrate of the same conductivity type and having a high inverse current gain value comprising a collector of the opposite conductivity type comprising both a heavily doped isolation barrier and a heavily doped buried layer, said isolation barrier extending through the epitaxial layer into contact with the buried layer, a base comprising a first region, a second region and a resistor portion connecting said first region to said second region, at least one emitter within said first region, a feedback emitter within said second region, and a base contact spanning the junction between the base and the feedback emitter forming a common contact to the base and said feedback emitter.
Claim 13
Dependent Claim
76 words
A transistor as claimed in claim 10 in which the cross sectional area of the base transverse to the direction of movement of charge carriers between the base contact and each emitter within the first region is smaller for the resistor portion than for the first region, and said resistor portion being defined between a first part of the collector and a second part of the collector extending between said first and said second 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) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |