Title :
Bipolar effects on the signal delay time in HBTs at high currents
Author :
Zhou, Haosheng ; Pulfrey, David L.
Author_Institution :
Dept. of Electr. Eng., British Columbia Univ., Vancouver, BC, Canada
fDate :
1/1/1993 12:00:00 AM
Abstract :
The signal delay time for GaAs-based n-p-n HBTs operating at high current densities has been investigated using a phenomenological transport model. It is shown that once base pushout commences, the electronic contribution to the signal delay decreases because of the reduced intervalley scattering associated with the weakened electric field in the collector. However, more importantly for practical considerations, it is also shown that the overall signal delay time increases because of the dominant role played by the slow-moving holes in the base pushout process
Keywords :
III-V semiconductors; carrier mobility; gallium arsenide; heterojunction bipolar transistors; semiconductor device models; GaAs; HBTs; base pushout; current densities; intervalley scattering; npn transistors; phenomenological transport model; signal delay time; slow-moving holes; weakened electric field; Charge carrier processes; Current density; Delay effects; Delay estimation; Gallium arsenide; Heterojunction bipolar transistors; Poisson equations; Scattering; Silicon; Space charge;
Journal_Title :
Electron Devices, IEEE Transactions on