Current gain rolloff in graded-base SiGe heterojunction bipolar transistors

Journal Article · Thu Apr 01 00:00:00 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]

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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), Vol. 14:4; ISSN 0741-3106
• Country of Publication: United States
• Language: English

Related Subjects

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