Gate oxide reliability of 4H-SiC MOS devices

The paper presents the reliability of MOS-based 4H-SiC devices. Recent high temperature gate oxide breakdown measurements on MOS capacitors reveal that the gate oxides on an as-grown epi surface are more reliable than those grown on ion-implanted and activated surfaces. The reduction in the oxide reliability on implanted surfaces is primarily due to the deterioration of surface morphology as a result of implant damage. In addition, preliminary measurements on forward I-V characteristics and threshold voltage of power MOSFETs under a constant applied gate voltage of +20 V show the devices to be stable up to 88 hrs of operation at room temperature.