Analysis and Mitigation of Single-Event Gate Rupture in VDMOS With Termination Structure

During heavy-ion experiments, the single-event gate rupture (SEGR) effects can still be observed in the vertical double-diffused power MOSFET (VDMOS) with radiation-hardened cells. Fault analysis demonstrates that the hot spots locate at the termination of the VDMOS. Then, several mitigation solutions for termination structure are discussed comprehensively by means of TCAD simulations. Finally, a combined hardness method with horizontally extending P+ region and adding floating N+ region is proposed. It is effective to reduce the electric field of gate oxide to below the calculated critical field, without additional masks and process steps.