New concept of collector design for 0.35 mu m BiCMOS driver based on a base pushout model in the presence of velocity overshoot

摘要

A novel concept of collector design is proposed for the 0.35 mu m BiCMOS driver. The optimum collector doping concentration, designed by a base pushout model with velocity overshoot, can be reduced to half of that without the velocity overshoot. Due to this reduction in the collector doping concentration, the collector-emitter breakdown voltage is improved from 2.7 V to 3.5 V. As a result, a 0.35 mu m BiCMOS driver which operates at 3.3 V supply voltage can be realized without sacrificing the switching speed.