On the fly oxide trap (otfot) concept: A new method for bias temperature instability characterization

Abstract

In this paper, a new method, named on the fly oxide trap (OTFOT), is proposed to extract the bias temperature instability BTI in MOS transistors. It is based on charge pumping technique (CP) at low and high frequencies. We emphasize on the theoretical-based concept, giving a clear insight on the easy-use of the OTFOT methodology and demonstrating its viability to characterize the negative BTI (NBTI). Using alternatively high and low frequencies, OTFOT method separates the interfacetraps (ΔNit) and border-trap (ΔNbt) (switching oxide-trap) densities independently as well as their contributions to the threshold voltage shift (ΔVth), without needing additional methods. OTFOT method can contribute to further understand the behavior of the NBTI degradation, especially through the threshold voltage shift components such as ΔVit and ΔVot caused by interface-trap and border-trap, respectively.