4H-SiC隐埋沟道MOSFET迁移率的研究(英文)

Study of Electron Mobility in 4H-SiC Buried-Channel MOSFETs

研究了几种因素对4H-SiC隐埋沟道MOSFET沟道迁移率的影响.提出了一个简单的模型用来定量分析串联电阻对迁移率的影响.串联电阻不仅会使迁移率降低,还会使峰值场效应迁移率所对应的栅压减小.峰值场效应迁移率和串联电阻的关系可用一个二次多项式来准确描述.详细分析了均匀分布和不均匀分布的界面态对场效应迁移率的影响.对于指数分布的界面态,低栅压下界面态的影响基本上可以忽略不计,随着栅压的增加,界面态的影响越来越显著.

The effects of several factors on mobility in 4H-SiC buried-channel （BC） MOSFETs are studied,A simple model that gives a quantitative analysis of series resistance effects on the effective mobility and field-effect mobility is proposed.A series resistance not only decreases field-effect mobility but also reduces the gate voltage corresponding to the peak field-effect mobility. The dependence of the peak field-effect mobility on series resistance follows a simple quadratic polynomial. The effects of uniform and exponential interface state distributions in the forbidden band on field-effect mobility are analyzed with an analytical model. The effects of non-uniform interface states can be ignored at lower gate voltages but become more obvious as the gate bias increases.