A new 1200 V-class edge termination structure with trench double field plates for high dV/dt performance

In this paper, a new 1200 V-class edge termination structure with trench double field plates is proposed and experimentally demonstrated. The double field plates are buried inside the trench. One of the field plates is for modulating electric field distributions along the trench and shifting the breakdown point to the active region for achieving the ideal planar junction breakdown voltage, and the other one is for stopping the depletion region extension at the right side of the trench to achieve high dV/dt performance. The fabricated device has a breakdown voltage of 1422 V which is verified as the ideal planar junction breakdown voltage. Furthermore, it is with a record-short edge termination length of 78 μm which is less than one-fifth of conventional guard ring approaches. Besides, it can handle a high dV/dt value of 73 kV/μs even at a bus voltage of 1400 V.