Current gain rolloff in graded-base SiGe heterojunction bipolar transistors

Journal Article · Wed Mar 31 23:00:00 EST 1993 · IEEE Electron Device Letters (Institute of Electrical and Electronics Engineers); (United States)

DOI:https://doi.org/10.1109/55.215153· OSTI ID:6508614

Crabbe, E F; Cressler, J D; Patton, G L; Stork, J M.C.; Comfort, J H; Sun, J Y.C. ^[1]

---

1. Thomas J. Watson Research Center, Yorktown Heights, NY (United States)

The authors report the experimental observation of a novel effect in SiGe heterojunction bipolar transistors (HBT's) with graded bases which results in a significant emitter-base bias dependence of the current gain. The nonideal collector current is caused by the interaction of the bias dependence of the emitter-base space-charge region width and the exponential dependence of the collector current on the germanium concentration at the edge of the space-charge region. The resulting current gain rolloff must be taken into account for accurate modeling of bipolar transistors with bandgap grading in the base.

• OSTI ID: 6508614
• Journal Information: IEEE Electron Device Letters (Institute of Electrical and Electronics Engineers); (United States), Journal Name: IEEE Electron Device Letters (Institute of Electrical and Electronics Engineers); (United States) Vol. 14:4; ISSN 0741-3106; ISSN EDLEDZ
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
426000* -- Engineering-- Components
Electron Devices & Circuits-- (1990-)
AMPLIFICATION
CURRENT DENSITY
CURRENTS
DATA
ELECTRIC CURRENTS
EXPERIMENTAL DATA
GAIN
GERMANIDES
GERMANIUM COMPOUNDS
HETEROJUNCTIONS
INFORMATION
JUNCTION TRANSISTORS
JUNCTIONS
NUMERICAL DATA
SEMICONDUCTOR DEVICES
SEMICONDUCTOR JUNCTIONS
SILICON COMPOUNDS
TEMPERATURE DEPENDENCE
TRANSISTORS