Influence of charge balance on the robustness of trench-based super junction diodes

Abstract One of the most important process parameters impacting the electrical performance in Super Junction (SJ) devices is the Charge Balance (CB). This paper demonstrates that the avalanche current capability in SJ diodes is not only dependent on the CB of the structure but also on the periphery design. It is observed from infrared (IR) thermography that the conducting area during Unclamped Inductive Switching (UIS) differs by modifying CB. These measurements are combined with TCAD simulations to link the failure mechanism to the appearance of a negative resistance branch in the I–V characteristic.

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