摘要
本文提出了一个适用于大电流的SiGe基区双极型晶体管(SiGe-HBT)的电流和频率特性的解析模型.本模型考虑了速度饱和效应,对n+pnn+双极型晶体管,当电流超过发生Kirk效应的临界电流时,本模型考虑了集电结附近由窄到宽的禁带变化对集电极电流和特征频率fT的影响.解析模型的计算结果同数值模拟结果一致,证明了解析模型是可信和精确的.本模型可用于器件设计和电路模拟.
Abstract This paper describes an analytical SiGe-base HBT model including the effects of velocity saturation on the collector current and cut-off frequency. The narrow-to-wide bandgap transition at the base-collector junction of npn device causes accelerated fT roll off when the current exceeds the knee current for the Kirk effect. Good agreement with SEDAN-3 simulation is obtained. This model can be used in the device design and the circuit simulation.