基于改进HTGB试验的SiC MOSFET栅极可靠性研究  

Research on Gate Reliability of SiC MOSFET Based on Improved HTGB Test

作　　者：熊一 廖晓红 柯方超 王成智 XIONG Yi;LIAO Xiao-hong;KE Fang-chao;WANG Cheng-zhi(State Grid Hubei Economic Research Institute,Wuhan 430000,China;不详)

机构地区：[1]国网湖北省电力有限公司经济技术研究院,湖北武汉430000 [2]国网湖北省电力有限公司,湖北武汉430000

出　　处：《电力电子技术》2021年第12期36-39,共4页Power Electronics

基　　金：国家重点研发计划(2016YFC0600804)。

摘　　要：碳化硅(SiC)金属氧化物半导体场效应晶体管(MOSFET)器件的栅极可靠性考核是一项重要的可靠性测试项目,然而现行测试表征均是针对硅(Si)器件制定的,并未充分考虑SiC器件的特性。这里以阈值电压为栅极老化表征参数,首先对SiCMOSFET器件进行传统静态高温栅偏(HTGB)试验,发现阈值电压弛豫效应对测量结果影响较大,于是对测量方法进行了改进;然后进行了更加贴近实际工况的动态HTGB试验,并研究了不同开关频率和占空比对测得结果的影响,结果表明开关频率越高阈值电压漂移越小,而占空比越高阈值电压漂移越大。进一步的,提出“有效偏压值”的概念来解释占空比对阈值电压漂移的影响机制,同时也建立了静态HTGB试验和动态HTGB试验的转换关系。The gate reliability assessment of silicon carbide(SiC) metal oxide semiconductor field effect transistor(MOSFET) is an important reliability test issue.However,the current standards are all formulated for silicon(Si) devices,and the characteristics of SiC devices are not fully considered.The threshold voltage is used as the gate aging characterization parameter.Firstly,the traditional static high temperature gate bias(HTGB) test is performed on SiC MOSFET,it is found that the threshold voltage hysteresis effect has a greater impact on the measurement results,so the measurement method is improved in this work.Then a dynamic HTGB test closer to the actual working conditions is carried out,and the influence of different switching frequencies and duty cycles on the measured results is studied.The results show that the higher the switching frequency,the smaller the threshold voltage drift,and the higher the duty cycle,and greater the threshold voltage drift.Furthermore,the concept of "effective bias value" is proposed to explain the influence mechanism of the duty cycle on the threshold voltage drift,and the conversion relationship between the static HTGB test and the dynamic HTGB test is also established.

关 键 词：金属氧化物半导体场效应晶体管 高温栅偏试验 阈值电压漂移 

分 类 号：TN32[电子电信—物理电子学]