Breakthrough in Channel Mobility Limit of Nitrided Gate Insulator for SiC DMOSFET with Novel High-temperature N2 Annealing

We have improved the limited channel mobility of nitridation on silicon carbide Si-face planar MOSFET to 50 cm
²
/Vs with the newly developed gate insulator process. Using the novel high-temperature N
₂
annealing process, nitrogen whose density is twice that of the nitrogen used in the conventional NO
_x
process can be introduced to the MOS interface. The developed N
₂
annealing is applied to a 1.2 kV class vertical MOSFET and remarkable reduction of the on-resistance has been demonstrated.