Analysis of a drain-voltage oscillation of MOSFET under high dV/dt UIS condition

In this paper, we investigate a mechanism of drain-voltage oscillation of MOSFET under high dV/dt UIS condition by using numerical simulation and experiments. One of the trigger events of the oscillation is found to be the current path switching between the active region and the termination region with close BVDSS characteristics. By optimizing the device parameters to make appropriate the BVDSS balance, avalanche capability is improved over ∼ 40%, enabling the oscillation-free turn-off.