Non-equilibrium transport in ultra-fast InGaAs/InP heterostructure bipolar transistors

The physics of non-equilibrium electron transport in ultra-fast InGaAs/InP heterojunction bipolar transistors (HBTs) is discussed. The forward transit delay was measured as a function of temperature from 340 K to 150 K. The small value of tau /sub F/=0.28 ps at a lattice temperature of 150 K is due to the dominance of high velocity ( upsilon approximately 6*10/sup -7/ cm-s/sup -1/) Gamma -valley electron transport in the base and collector. It is shown that optic-phonon and electron-electron scattering must be considered to properly describe the temperature dependence of electron transport in the collector.<
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