SiGe异质结晶体管频率特性模型研究

A Study on Modeling of Frequency Characteristics for SiGe HBT's

在分析载流子输运和分布的基础上,建立了SiGe异质结晶体管(HBT)各时间常数模型;在考虑发射结空间电荷区载流子分布和集电结势垒区存在可动电荷的基础上,建立了SiGeHBT发射结势垒电容模型和不同电流密度下包括基区扩展效应的集电结势垒电容模型。对SiGeHBT特征频率及最高振荡频率与电流密度、Ge组分、掺杂浓度、结面积等之间的关系进行了模拟,对模拟结果进行了分析和讨论。

Based on the analysis of carrier transportation and distribution,various time constant models,including relations between time constants and parameters of the device structure and the current density in SiGe HBT's,are described.The base expansion effect is also taken into account in these models.The dependency of f_T and f_(max) on the current density,Ge content,doping concentration,and junction area is simulated.The results are analyzed and discussed as well.