锗硅异质结双极型晶体管RF雪崩效应Mextram模型研究  

Research on Mextram Model of Germanium Silicon Heterojunction Bipolar Transistor with RF Avalanche Effect

作　　者：刘静[1] 郑少华 刘茵 LIU Jing;ZHENG Shao-hua;LIU Yin(Department of Electronic Engineering,Xi’an University of Technology,Xi’an,Shaanxi 710048,China)

机构地区：[1]西安理工大学电子工程系,陕西西安710048

出　　处：《电子学报》2023年第6期1493-1499,共7页Acta Electronica Sinica

基　　金：陕西省重点研发计划(No.2022GY-016)。

摘　　要：传统Mextram模型基于雪崩倍增电流源Iavl来描述硅锗异质结双极晶体管的雪崩倍增效应,忽略了射频条件下因雪崩倍增相位延迟以及载流子传输时间延迟带来的集电结电感延迟问题.对硅锗异质结双极晶体管的雪崩倍增效应进行了研究,解释了导致器件集电结中出现电感延迟的物理机制.提出采用击穿电感和电阻分别表征器件的(Radio Frequency,RF)电感延迟特性和雪崩倍增载流子的贡献,建立考虑RF雪崩倍增效应的电感击穿等效电路模型,并嵌入到Mextram 505.00模型中.基于S参数来描述改进模型的验证结果,与传统模型相比,改进模型在应用频率小于35 GHz条件下,显著改善了硅锗异质结双极晶体管的增益和输出阻抗的精度,且不会对器件模型的直流特性拟合精度产生负面影响.同时从改进模型的电子击穿电感Ljcn、电子击穿电阻Rjcn、输出曲线、增益参数和输出阻抗中提取等效电路模型的敏感参数Aem和Vg.结果表明,基于RF电感击穿等效电路的Mextram 505.00改进模型可以更精确地预测射频条件下雪崩倍增效应发生时硅锗异质结双极晶体管的器件性能.The avalanche current source Iavl is used to model the avalanche multiplication effect in the traditional SiGe HBT Mextram model,which ignores the base-collector junction inductance delay characteristics due to avalanche mul⁃tiplication phase delay and carrier transit-time delay under RF(Radio Frequency)conditions.The avalanche multiplication effect is studied and its physical mechanism leading to the inductance delay of SiGe HBT is explained.The breakdown in⁃ductance and breakdown resistance are proposed to characterize the contribution of RF inductance delay and avalanche mul⁃tiplication carriers respectively.The RF avalanche multiplication effect inductive breakdown equivalent circuit is estab⁃lished and it is embedded in Mextram 505.00 model.The S-parameters are used to describe the verification process of the improved model.Compared to the traditional model of the device,the accuracy of the device gain and the output imped⁃ance of the improved model is greatly improved in the range of 1~35 GHz.The DC characteristics of the device will not be sacrificed.Meanwhile,the sensitive parameters Aem and Vg are extracted from the electronic breakdown inductance Ljcn,electronic breakdown resistance Rjcn,output curve,gain parameter and device output impedance of the improved model.The results show that the improved model with RF inductive breakdown equivalent circuit can predict accurately the perfor⁃mance of SiGe HBT with avalanche multiplication effect under RF conditions.

关 键 词：HBT Mextram模型 参数提取 RF雪崩倍增效应 碰撞电离 

分 类 号：TN431[电子电信—微电子学与固体电子学]