基于栅极泄漏电流的碳化硅MOSFET短路栅源极失效判定方法  

Determination Method for Short-circuit Gate-source Failures of Silicon Carbide MOSFET Based on Gate Leakage Current

作　　者：彭娇阳 孙鹏[1] 张浩然[1] 蔡雨萌 赵志斌[1] PENG Jiaoyang;SUN Peng;ZHANG Haoran;CAI Yumeng;ZHAO Zhibin(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206

出　　处：《高电压技术》2022年第6期2391-2400,共10页High Voltage Engineering

基　　金：国家重点研发计划(2018YFB0905703)。

摘　　要：碳化硅金属氧化物半导体场效应晶体管(metal-oxide-semiconductor field-effect transistor, MOSFET)的短路坚固性是影响器件在高压高频功率变换领域应用的关键问题。在传统的碳化硅MOSFET栅源极短路研究中,依据器件关断后的波形中栅源极电压u GS的上升判定是否发生短路失效。首先分析了这种传统的栅源极短路判定方法,指出其存在的u GS上升不明显问题将导致判定结果不准确。进而通过对碳化硅MOSFET栅源极短路的失效机理进行分析,提出了基于碳化硅MOSFET的静态参数——栅极泄漏电流IGSS的栅源极失效判定方法。然后搭建了碳化硅MOSFET短路实验平台,通过测量短路过程中IGSS的变化情况验证了所提出的判定方法的有效性及可行性。最后对比了2种判定方法的参数灵敏度、短路耐受时间和临界短路能量。结果表明,相比于传统判定方法,所提出的栅源极失效判定方法灵敏度提高了7倍以上,能够更准确地识别碳化硅MOSFET是否发生栅源极失效。上述分析有利于在实际应用中准确识别短路故障后器件的损坏状态,进而提高碳化硅MOSFET在高压应用中的可靠性和经济性。The short-circuit robustness of silicon carbide metal-oxide-semiconductor field-effect transistor(MOSFET) is a key issue that affects the application of the device in the field of high-voltage and high-frequency power conversion. In the traditional SiC MOSFET gate-source short-circuit research, whether the short-circuit failure occurs is determined according to the rise of the gate-source voltage u GS in the waveform after the device is turned off. Firstly, this traditional gate-source short-circuit judgment method is analyzed, and it is pointed out that the problem that the u GS rise is not obvious will lead to inaccurate judgment results. Furthermore, by analyzing the failure mechanism of SiC MOSFET gate-source short circuit, a gate-source failure judgment method based on the static parameter of SiC MOSFET—gate leakage current IGSS is proposed. Then, an experimental platform for short circuit of SiC MOSFET is built, and the validity and feasibility of the proposed judgment method are verified by measuring the change of IGSS during the short circuit process. Finally, the parameter sensitivity, short-circuit withstand time, and critical short-circuit energy of the two judgment methods are compared. The results show that the sensitivity of the proposed gate-source failure determination method is more than 7 times higher than that of the traditional determination method, and it can more accurately identify whether the gate-source failure occurs in the silicon carbide MOSFET. The above analysis is conducive to accurately identifying the damage state of the device after a short-circuit fault in practical applications, thereby improving the reliability and economy of silicon carbide MOSFETs in high-voltage applications.

关 键 词：碳化硅MOSFET 栅极泄漏电流 栅源极失效 栅源极短路 判定方法 

分 类 号：TN386[电子电信—物理电子学]