Difference analysis method for negative bias temperature instability lifetime prediction in deeply scaled pMOSFETs

Abstract

The fluctuation significantly affects the lifetime prediction of negative bias temperature instability (NBTI) for deeply scaled pMOSFETs. In this paper, we present a novel difference method to separate the time dependent fluctuation-related component from the NBTI quasi-static component in the threshold voltage shift. The extracted fluctuation-related component exhibits weak temperature and time dependences which is consistent with the characteristic of as-grown defect-induced trapping and detrapping while the quasi-static component presents electrical behaviors of generated-defect-induced NBTI degradation. On the basis of these results, a composite NBTI model is constructed and lifetime projection is derived for the small pMOSFETs.