Impact of Mechanical Strain on GIFBE in PD SOI p-MOSFETs as Indicated From NBTI Degradation

Abstract

This letter investigates the impact of mechanical strain on gate-induced floating-body effect in partially depleted silicon-on-insulator p-channel metal-oxide-semiconductor field-effect transistors. The strained FB device has less NBTI degradation than unstrained devices. This behavior can be attributed to the fact that more electron accumulation induced by strain effect reduces the electric oxide field significantly during NBTI stress. Analysis of the body current (I-B) under source/drain grounded and floating operation indicates an increase in the anode electron injection and electron tunneling from conduction band which occur at the partial n(+) poly-Si gate and Si substrate, respectively. This phenomenon can be attributed to the bandgap narrowing which has been induced by the strain effect.