Active solid-state devices (e.g. – transistors – solid-state diode – Bipolar transistor structure – With base region having specified doping concentration...
Reexamination Certificate
2006-01-24
2006-01-24
Flynn, Nathan J. (Department: 2826)
Active solid-state devices (e.g., transistors, solid-state diode
Bipolar transistor structure
With base region having specified doping concentration...
C257S565000
Reexamination Certificate
active
06989581
ABSTRACT:
A bipolar transistor with vertical geometry comprises a base region (1) provided with a base contact (21), emitter and collector regions (2,3) arranged to extract minority carriers from the base region, and an excluding structure for counteracting entry of minority carriers into the base region via the base contact, wherein the base region has a bandgap of greater than 0.5 eV and a doping level greater than 1017cm−3. As shown the base includes an excluding heterojunction (4) preventing entry of carriers from the base contact (21), but alternatively the base region could comprise a “high-low” doping homojunction. The construction shows improved resistance to thermal runaway even in multi-finger transistors. It is particularly useful for high power, high frequency transistors, e.g. base on gallium indium arsenide. The collector region preferably has a heterostructure.
REFERENCES:
patent: 3868720 (1975-02-01), New et al.
patent: 4617724 (1986-10-01), Yokoyama et al.
patent: 5494836 (1996-02-01), Imai
patent: 6365477 (2002-04-01), Gassler et al.
patent: 0 384 113 (1990-08-01), None
patent: 05-114602 (1993-05-01), None
patent: 11-312685 (1999-11-01), None
Streetman, “Solid State Electronic Devices,” 1990, Prentice Hall, third edition, p. 272-274.
Bayraktaroglu, et al. “Very High-Power-Density CW Operation of GaAs/AlGaAs Microwave Heterojunction Bipolar Transistors”,IEEE Electron Device Letters, pp. 493-495 (1993).
Liou, et al., “Thermal Stability Analysis of Multiple Emitter Finger Microwave AlGaAs/GaAs Heterojunction Biopolar Transistors”,IEEE MIT-3 Digest, pp. 281-284 (1993).
McDonnell Boehnen & Hulbert & Berghoff LLP
Qinetiq Limited
Quinto Kevin
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