Comparison of the instability in device characteristics for thin-film SOI power n- and p-MOSFETs at high temperature under AC stress

Abstract

In this study, we compare the device instability (hot carrier effect, negative bias temperature instability (NBTI), and positive bias temperature instability (PBTI)) of a thin-film Silicon on Insulator (SOI) power n-MOSFET and p-MOSFET at a high temperature under AC stress. For a p-MOSFET, the degradation rate of the on-resistance increases with an increase in temperature beyond 373 K. Contrarily, for an n-MOSFET, the degradation rate decreases with an increase in temperature. For a p-MOSFET, the threshold voltage shift increases with an increase in temperature due to the NBTI, whereas, for an n-MOSFET, it decreases with an increase in temperature. This is because the hot carrier effect decreases with an increase in temperature under AC stress. In this study, we clarify that the instability mechanism of the p-MOSFET under AC stress is different from that of the n-MOSFET.