A Physical and SPICE Mobility Degradation Analysis for NBTI

The importance of mobility degradation (Δμ_eff) due to Negative Bias Temperature Instability (NBTI) stress is studied for precise modeling of p-MOSFET drain current degradation (ΔID). An improvement to the SPICE mobility model is presented to incorporate Δμ_eff , and the modified model is validated against experimental ΔID and transconductance degradation (Δgm) over time, in the subthreshold to strong inversion region, across different SiON and high-k metal gate (HKMG) devices. To gain further insight into NBTI mobility degradation, the well-known physics-based mobility model consisting of three scattering components is revalidated across different devices. This analysis is beneficial for device and circuit simulations in Technology CAD and SPICE environments, respectively, for different process technologies.