Heterojunction bipolar transistors and method of manufacture

Details Heterojunction bipolar transistors and method of manufacture Heterojunction bipolar transistors and method of manufacture

1989-04-07

1990-07-03

James, Andrew J.

357 16, 357 36, 357 47, 357 81, H01L 2972

Patent

active

049395629

ABSTRACT:
A heterojunction bipolar transistor for high power applications in the microwave and millimeter wave regions is described. The heterojunction bipolar transistor includes a substrate having disposed thereover an emitter layer comprised of doped aluminum gallium arsenide and a composite base layer including a first layer of doped gallium arsenide disposed on the emitter to form a heterojunction. A second layer of doped indium gallium arsenide is disposed on the first base layer to provide a composite base. Disposed over the indium gallium arsenide layer is a gallium arsenide layer which acts as the collector. When etching the gallium arsenide layer to define the collector, the indium gallium arsenide layer acts as an etch stop to protect the underlying gallium arsenide layer and provide a smooth bath region to form base contacts. Emitter contact is provided to this device by etching via holes to electrically and thermally connect the emitter contact to a ground plane conductor, thus providing a heterojunction bipolar transistor in common emitter configuration. In an alternate embodiment, a composite emitter of a narrow band gap etch stop layer and wide band gap layers are provided. The composite emitter acts as an etch stop during via hole definition and facilitates ohmic contact to the emitter.

REFERENCES:
patent: 4586071 (1986-04-01), Tiwari
patent: 4661836 (1987-04-01), Mun
patent: 4679305 (1987-07-01), Morizuka
patent: 4692791 (1987-09-01), Bayraktaroglu
patent: 4758870 (1988-07-01), Hase et al.
"Non-Alloyed Submicron Resonant Tunneling Device", IBM Technical Disclosure Bulletin, Mar. 1989, vol. 31, No. 10, pp. 150-152.
Fritz et al., "Critical Layer Thickness in In.sub.0.2 Ga.sub.0.8 As/GaAs Single Strained Quantum Well Structures", Applied Physics, Sep. 28, 1987, vol. 51, No. 13, pp. 1004-1006.
G. J. Sullivan et al., "AlGaAs/InGaAs/GaAs Strained-Layer Heterojunction Bipolar Transistors by Molecular Beam Epitaxy", Electronics Letters, vol. 22, No. 8, Apr. 10, 1986, pp. 419-421.
Herbert Kroemer, "Heterostructure Bipolar Transistors and Integrated Circuits", Proceedings of the IEEE, vol. 70, No. 1, Jan. 1982, pp. 13-25.
B. Bayraktaroglu et al., "AlGaAs/GaAs Heterojunction Bipolar Transistors for Power Applications", IEEE, (1987), pp. 265-273.
Naresh Chand et al., "Doping Effects and Compositional Grading in Al.sub.x Ga.sub.1-x As/GaAs Heterojunction Bipolar Transistors", IEEE Transactions on Electron Devices, vol. ED-32, No. 6, Jun. 1985, pp. 1064-1069.
Mukunda B. Das, "High-Frequency Performance Limitations of Millimeter-Wave Heterojunction Bipolar Transistors", IEEE Transactions on Electron Devices, vol. 35, No. 5, May 1988, pp. 604-614.
Mau-Chung F. Chang et al., "AlGaAs/GaAs Heterojunction Bipolar Transistors Fabricated Using a Self-Aligned Dual-Lift-Off Process", IEEE Electron Device Letters, vol. EDL-8, No. 7, Jul. 1987, pp. 303-305.

Affiliated with

Also associated with

Rating

Heterojunction bipolar transistors and method of manufacture does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Heterojunction bipolar transistors and method of manufacture, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heterojunction bipolar transistors and method of manufacture will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1894376