SJ-MOSFET with wave-type field limiting ring for high di/dt robustness of body diode reverse recovery

In this letter, a novel Superjunction Metal-Oxide -Semiconductor Field Effect Transistor with wave-type field limiting ring (WFLR-SJ-MOSFET) is proposed to improve the di/dt robustness of body diode reverse recovery. When SJ-MOSFET body diode goes through reverse recovery, the WFLR can suppress and rebuild the peak electric field which is resulted from the large current flowing through the sensitive terminal boundary region. As a consequence, the ruggedness of dynamic avalanche during reverse recovery is optimized. Finally, the di/dt robustness of WFLR-SJ-MOSFET body diode reverse recovery is improved by 3.2 times from 72 A/μs to 320 A/μs comparing with the conventional SJ-MOSFET.