SiC MOSFET静动态参数温度特性的实验研究

Experimental Study of Temperature Characteristics of Static and Dynamic Parameters of SiC MOSFET

为评估器件结温对碳化硅(SiC)金属氧化物半导体场效应管(MOSFET)开关瞬态过程的影响,以Cree第2代1 200 V/36 A SiC MOSFET为研究对象,利用B1505A功率器件分析仪/曲线追踪仪和双脉冲测试平台在不同温度下对器件的静动态特性进行实验。并且对比了不同温度下开关延时时间、开关电气应力(开通电流过冲和关断电压过冲)及开关能量损耗的差异。研究结果表明:SiC MOSFET开通延时具有负温度系数,而关断延时具有正温度系数。此外,SiC MOSFET的开通电流变化率和电压变化率的绝对值随温度升高而逐渐增大,而关断电流变化率的绝对值和电压变化率却具有相反的规律,因此随着温度升高,开通过程越快,开通电流过冲增大,但开通损耗会随之减小,而关断过程越慢,关断电压过冲减小,关断损耗却会随之增大,致使总开关损耗几乎不变。

To assess the effect of junction temperature on silicon carbide （SIC） metal-oxide semiconductor field effect transistor（MOSFET） during switching transient process, the static and dynamic transient characteristics of Cree second-generation 1 200V/36 A SiC power MOSFET are measured at different temperatures using B1505A power device analyzer/curve tracker and double pulse text platform.And comparing the difference of switch delay time,switch electrical stress（current overshoot and voltage overshoot） and switch energy loss at different temperatures.Results of this study show that turn-on delay time have negative temperature coefficient and correspondingly positive for turn-off delay time.In addition,the current change rate and voltage change rate absolute value during turn-on transient would increase with temperature,but the opposite regular for current change rate absolute value and voltage change rate during turn-off transient.Hence, SiC MOSFET have the higher-speed turn-on transient, the higher current overshoot and the lower turn-on loss under higher temperature.On the contrary,the slower turn-off transient,the lower voltage overshoot and higher turn-off loss.Therefore, it will make the total switching loss nearly keep constant.