4H-SiC金属-半导体场效应晶体管大信号I-V特性和小信号参数的计算

Evaluation of DC I-V Characteristics and Small Signal Parameters of 4H-SiC Metal-Semiconductor Field Effect Transistors

基于碳化硅金属-半导体场效应晶体管内部载流子输运的物理特性分析,建立适于精确计算4H-SiCMESFET器件大信号电流-电压特性和小信号参数的解析模型.该模型采用场致迁移率、速度饱和近似,并考虑碳化硅中杂质不完全离化效应及漏源串联电阻的影响,栅偏置为0 V时,获得最大跨导约为48 mS.mm-1.计算结果与实验数据有很好的一致性.该模型具有物理概念清晰且计算较为准确的优点,适于SiC器件以及电路研究使用.

With analysis on internal carrier transport mechanism in silicon carbide（SiC）,an improved analytical model for dc current voltage and small signal parameters of 4H-SiC metal-semiconductor field effect transistor（MESFET） is proposed considering carrier velocity saturation and charge controlling.Incomplete dopant ionization and parasitic drain-source resistances are considered simultaneously.The simulated maximum transconductance is 48 mS.mm-1 at a gate voltage of 0 V.Simulations and physical measurements show good agreement.The model is simple in calculation and distinct in physical mechanism.It is suitable for design and research of SiC devices and circuits.