SiGe HBT大信号扩散电容模型研究

Study of SiGe HBT Large Signal Diffusion Capacitance Models

基于SiGeHBT(异质结双极晶体管)大信号等效电路模型,建立了SiGeHBT大信号发射结扩散电容模型和集电结扩散电容模型。该模型从SiGeHBT正反向传输电流出发,研究晶体管内可动载流子所引起的存储电荷(包括正向存储电荷和反向存储电荷)的基础上,同时考虑了厄利效应对载流子输运的影响,其物理意义清晰,拓扑结构简单。将基于大信号扩散电容模型的SiGeHBT模型嵌入PSPICE软件中,实现对SiGeHBT器件与电路的模拟分析。对该模型进行了直流特性模拟分析,直流模拟分析结果与文献报道的结果符合得较好,瞬态特性分析结果表明响应度好。

Based on the SiGe HBT （Heterojunction Bipolar Transistor） large signal equivalent circuit model, SiGe HBT models of the emitter diffusion capacitances and the collector diffusion capacitances are erected. Grounded on the forward transmit current and the inverse transmit current, it is taken into account the movable charge storage effect induced by the movable carries （including the forward storage charge and the inverse storage charge） , taking the Early Effect influence on carrier transport. The model holds the features of definite physical meaning and simple topology. And the large signal diffusion capacitances model, based on SiGe HBT equivalent circuit model, is embedded in the PSPICE. The model is simulated and analyzed in DC by the PSPICE, and the DC simulation results accord to that of other literatures, and transient state simulation results indicate that the response characteristic is good.