Heterojunction bipolar transistor

Details Heterojunction bipolar transistor Heterojunction bipolar transistor

1997-07-14

1999-10-05

Jackson, Jr., Jerome

Active solid-state devices (e.g., transistors, solid-state diode

Heterojunction device

Bipolar transistor

257197, 250214A, H01L 29737

Patent

active

059628804

ABSTRACT:
A self-aligned bipolar transistor which has a small base resistance and small emitter-base and collector-base capacitances and is operable at high speed is disclosed. This bipolar transistor is characterized in that a low concentration collector region made of single crystal Si--Ge is self-alignedly formed between an intrinsic base of single crystal Si--Ge and an intrinsic base, and that an extrinsic base electrode and an intrinsic base are connected only through a doped external base. With this arrangement, an energy barrier is not established at the collector base interface owing to the formation of the low concentration region of single crystal Si--Ge, so that the transit time of the carriers charged from the emitter is shortened. The connection between the intrinsic base and the extrinsic base electrode via the doped external base results in the reduction of the base resistance. In addition, the self-aligned formation of the emitter-base-collector leads to the reduction in capacitance between the emitter and the base and also between the collector and the base. Accordingly, a high-speed bipolar transistor can be realized and thus, circuits using the transistor are operable at high speed.

REFERENCES:
patent: 4451916 (1984-05-01), Casper
patent: 5087892 (1992-02-01), Hayashi
patent: 5302841 (1994-04-01), Yamazaki
patent: 5323032 (1994-06-01), Sato et al.
patent: 5440152 (1995-08-01), Yamazaki
patent: 5494836 (1996-02-01), Imai
patent: 5508537 (1996-04-01), Imai
Rosenfeld et al., "The Composition Dependence of the Cut-Off Frequencies of Ungraded Si.sub.1-x Ge.sub.x /Si.sub.1-y Ge.sub.y /Si.sub.1-x Ge.sub.x HBTs", Solid State Electronics, vol. 38, No. 3, Mar. 1, 1995.
"Heterojunction Bipolar Transistor Using Si Alloyed with Ge for Greater Base Band Gap Reduction", IBM Technical Disclosure Bulletin, vol. 33, No. 5, Oct. 1990.
"Selective Epitaxial Growth of Si.sub.1-x Ge.sub.x Base by UHV-CVD" by M. Hirol et al., Microelectronics Research Labs, NEC Corp. pp. 19-24.

Affiliated with

Also associated with

Rating

Heterojunction bipolar transistor 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 transistor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heterojunction bipolar transistor will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1174417