Patent US5625205A successfully refreshed from Google Patents.
US5625205A
Expired / Lapsed
US
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Bipolar transistor circuit
Assignee: NEC Corp
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Filing: 1996-09-24
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Granted: 1997-04-29
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Expires: 2016-09-24
Abstract
Abstract In an NPN type bipolar transistor, by employing AlGaAs or InGaAs having greater band gap than silicon, for an emitter and a base, doping amount of the emitter can be made smaller than that of the base to permit improvement of reverse withstanding voltage between the base and the emitter. Therefore, B class or C class bias can be used in a microwave band to improve efficiency.
Inventors
- 👤 Noboru Kusama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:04
CPC Classifications
H; H10; H10D; H10D10/00; H10D10/80; H10D10/821; H03; H03F; H03F3/00; H03F3/189; H03F3/19; H03F3/191; H03F3/60; H03F3/602; H03F2200/00; H03F2200/06; H03F2200/09; H03F2200/171; H03F2200/222; H03F2200/366; H03F2200/387
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
148 words
A bipolar transistor circuit for use in a microwave high output amplifier, comprising: an NPN-type hetero-junction bipolar transistor used as an active element for amplification and including an emitter formed as an emitter layer of AlGaAs, a base formed of AlGaAs, and a collector, said bipolar transistor further comprising a high resistance or P - semiconductor layer having a smaller electron affinity than a semiconductor of said base, said semiconductor layer being provided around a periphery of said emitter layer and having a portion extending towards said collector to overlap a laterally exposed part of said base layer and a laterally exposed part of said collector; and amplifying means comprising an inductance connected between said base and a ground, said emitter being connected to the ground, wherein a microwave signal is inputted to said base and an amplified signal is outputted from the collector of said bipolar transistor.
Claim 2
Dependent Claim
148 words
A bipolar transistor circuit for use in a microwave high output amplifier, comprising: an NPN-type hetero-junction bipolar transistor used as an active element for amplification and including an emitter formed as an emitter layer of AlGaAs, a base formed of AlGaAs, and a collector, said bipolar transistor further comprising a high resistance or P - semiconductor layer having a smaller electron affinity than a semiconductor of said base, said semiconductor layer being provided around a periphery of said emitter layer and having a portion extending towards said collector to overlap a laterally exposed part of said base layer and a laterally exposed part of said collector; and amplifying means comprising an inductance connected between said base and a ground, said emitter being connected to the ground, wherein a microwave signal is inputted to said base and an amplified signal is outputted from the collector of said bipolar transistor.
References Cited (Backward Citations)
JPS55103777A
Cited
JPS6239063A
Cited
JPS62141771A
Cited
JPS62141772A
Cited
JPS62141770A
Cited
US4847568A
Cited
US4807008A
Cited
EP0359508A2
Cited
US5010382A
Cited
US5073812A
Cited
US5212103A
Cited
JPH0499382A
Cited
US5336909A
Cited
US5406227A
Cited
US5347229A
Cited
US5406224A
Cited
US5410158A
Cited
US5420589A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-04-28 | 2000-10-28 | 2001-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-04-28 | 2004-10-28 | 2005-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-04-28 | 2008-10-28 | 2009-04-29 | $7700.00 | Window Closed / Lapsed |