Current gain modeling of SiGe DHBTs in SPICE including retarding potential barrier effect

This paper presents an approach to model the current gain in SiGe DHBTs, by using the fitting coefficients to modify the model parameters of Si BJTs in OrCAD PSPICE. The effect of dynamic retarding potential barrier at base-collector heterojunction in SiGe DHBTs is also modeled by using a resistor in parallel with internal base resistance R
_B
.