Impact of negative bias temperature instability on p-channel power VDMOSFET used in practical applications

Abstract

Impact of the negative bias temperature instabilities (NBTI) on p-channel power vertical double diffused MOS (VDMOS) transistors was a subject of extensive research in previous years. It was shown that NBT stressing leads to degradation of some parameters, and among them, threshold voltage shift (ΔVT) was marked as one of the most important ones, because it directly impacts the lifetime in practical applications. Our earlier papers were primarily dealing with NBTI effects and responsible mechanisms in p- and n-channel power VDMOS transistors. However, this paper investigates NBTI effects in p-channel power VDMOSFETs under both static and different types of pulsed stressing signals, and their impact on the performances and reliability of DC motors driven by investigated devices.