Compact LDD nMOSFET degradation model

In this paper, we present a compact degraded I-V model for submicron lightly-doped drain (LDD) MOSFET's. The analytical and physics-based model was developed using the drift equation and considering the nonuniform spatial hot-carrier-induced interface states and the detailed LDD structure. It can be used to calculate fresh channel electric field and drain current by turning off the effect of hot-carrier-induced interface states. Using the fresh electric field in conjunction with a simplified energy balance equation, the nonuniform spatial distribution of induced interface states ran be calculated. By incorporating this distribution into the degraded current model, we can describe the damaged I-V characteristics and channel electric fields as a function of stress time. The model includes the effects of series resistances and carrier velocity saturation. It can be used to calculate time-dependent degraded drain current, and is a time-saving CAD model.