Effects of LaSiO_xThickness and Forming Gas Anneal Temperature on Threshold Voltage Instability of 4H-SiC MOSFETs With LaSiO_x

摘要

We report the effects of lanthanum-rich layer thickness and forming gas anneal (FGA) conditions on mobility and threshold voltage (${V} _{{ext {T}}}$) instability of high-mobility 4H-SiC MOSFETs using lanthanum silicate (LaSiO_x) interface engineering. MOSFETs with LaSiO_xafter high-temperature FGA show significantly improved${V} _{ext {T}}$reliability under positive gate bias. It is found that both the thickness of the initial lanthanum-rich layer and the FGA temperature profoundly influence MOSFET mobility and${V} _{ext {T}}$instability under positive bias. There is a tradeoff between mobility and${V} _{ext {T}}$shift under positive bias.