Floating-body kinks and dynamic effects in fully depleted SOI MOSFETs

Abstract

Fully depleted (FD) SOI CMOS is a contender for low-voltage IC applications. However, as FD/SOI MOSFETs are scaled, floating-body effects, which previously seemed insignificant, become important. In this paper, we report kinks in the measured subthreshold current-voltage characteristics of highly scaled FD/SOI MOSFETs, and we describe and model the underlying physical mechanism, showing how it differs from the familiar kink effect in partially depleted (PD) devices. The insight afforded qualifies the meaning of FD/SOI and implies new design issues for low-voltage SOI CMOS.