计及热电耦合效应的SiC MOSFET阈值电压精确监测方法

ACCURATE MONITORING METHOD OF SiC MOSFET THRESHOLD VOLTAGE CONSIDERING THERMOELECTRIC COUPLING EFFECT

摘要: 在研究SiC MOSFET的阈值电压、体二极管电压、漏-源极通态电阻温度依赖性的基础上，分析偏压温度不稳定性（BTI）引起的V_TH的漂移规律，并探究其对温敏电参数（TSEPs）的影响规律。另外，在充分考虑温度和BTI对V_TH共同作用的影响下，提出在小电流注入时使用体效应下的体二极管电压监测SiC MOSFET阈值电压的方法。该方法可在不同的结温（Tj）下监测阈值电压，为校正其他TSEPs测量结温的准确性提供帮助。理论和实验结果证明了该方法的可行性。

Abstract: This paper studies the temperature dependence of threshold voltage,body diode voltage,drain-source on-state resistance in SiC MOSFET,analyzes the effect of bias temperature instability（BTI）on V_TH,and explores the mechanism of its effect on temperaturesensitive electrical parameters（TSEPs）. In addition,considering the influence of temperature and BTI on V_TH,a method for threshold voltage monitoring employing SiC MOSFET body diode voltage under body effect at low current injection is proposed. The proposed method can monitor the threshold voltage at different junction temperatures（ Tj）and provides help for correcting the accuracy of junction temperature measurement by other TSEPs. The theoretical and experimental results demonstrate the feasibility of the proposed method.