器件特性参数对SiC MOSFET静动态均流影响的实验研究

Experimental Investigations of the Influences of Characteristic Parameters on Static and Dynamic Current Sharing of SiC MOSFET

碳化硅(SiC)MOSFET作为第三代半导体器件,与硅IGBT相比在高频、高温、高压的工况下性能更加优异。然而在并联应用中,不同器件之间较大的特性参数差异会影响并联均流的动静态特性。现有的SiC MOSFET并联均流研究并没有全面地分析器件参数对并联均流产生的影响。因此,测试了30个器件在通态电阻、阈值电压、跨导和寄生电容上的差异并理论分析了不同特性参数对并联动静态均流所造成的影响,设计了SiC MOSFET并联均流实验的平台,且在排除电路参数以及测量系统可能引入的误差的条件下,针对不同器件参数的差异度进行实验,最后综合理论分析和实验结果,得出SiC MOSFET不同器件特性参数的差异度分别对静动态均流的影响以及这些影响的综合作用关系。

As the third generation semiconductor device,silicon carbide（SiC） MOSFET has better performances at high frequencies,high temperatures and high voltages than silicon IGBT.However,the large characteristic parameter differences among devices in parallel applications will affect the static and dynamic characteristics of parallel current sharing.The existing researches about current sharing of parallel-connected SiC MOSFETs do not comprehensively analyze the effects of device parameters.Therefore,the differences of 30 devices in the on-state resistance,threshold voltage,transconductance and parasitic capacitance are tested,and the influences of different characteristic parameters upon static and dynamic current sharing of parallel-connected SiC MOSFETs are theoretically analyzed.The experimental platform for current sharing of parallel-connected SiC MOSFETs is designed.After ruling out the error influences caused by circuit parameters and measurement systems,experiments based on different device parameters are conducted.Finally,the theoretical analysis and experimental results show the influences of different characteristic parameters of SiC MOSFETs on the static and dynamic current sharing and the comprehensive effects of these influences.