The effects of floating body operation on hot carrier behavior in SOS MOSFETs

Abstract

Hot carrier effects in MOSFETs have been intensively investigated in both bulk silicon and SOI materials. However, there is a lack of hot carrier information in SOS MOSFETs. SOS material differs from bulk material in that electron mobility is lower while hole mobility remains unchanged. Reduced mobility is not observed for holes because the mechanical strain in the epitaxial layer due to lattice mismatch between sapphire and silicon lifts the degenerate valence band significantly to make SOSFETs light hole devices. Since hot hole injection into the oxide is commonly observed in devices biased at low gate voltages, it is of great interest to study the contributions of light hole injection to device degradation mechanisms in both floating and non-floating body operation conditions. In this work, we will investigate the behavior of light holes at the oxide interface, and examine the effects of light hole injection under floating body operation on device degradation.<>