Experimental and simulated investigation of −100 V rated P-channel UMOSFETs under heavy ion radiation

Abstract

In this paper, the heavy-ion irradiation experimental results of a − 100 V rated P-Channel conventional power U-shaped metal-oxide-semiconductor field-effect transistors (C-UMOSFET) are presented. The results show that the sample devices can avoid a drain leakage current or gate leakage current degradation under the bias conditions of VDS = −100 V and VGS = 0. However, a severe gate leakage current degradation occurs if VGS ≥ 5 V. On this basis, the heavy-ion simulation results for the −100 V rated C-UMOSFET and hardened UMOSFET (H-UMOSFET) are given. In the H-UMOSFET structure, a thick oxide layer of 0.2 μm under trench bottom is introduced to improve the SEGR performance. The simulation results show that, the electric field peak in the gate oxide at bottom can be significantly reduced to present better SEGR performance.