Physics based PBTI model for accelerated estimation of 10 year lifetime

Threshold voltages (V_t) in high κ nFETs are observed to shift under prolonged positive gate bias stressing. This bias induced V_t shift (ΔV_t) is referred as PBTI and is an important reliability issue. In this paper, we extend a previously proposed PBTI model to include de-trapping kinetics. The proposed model is verified by comparing calculated results with PBTI data measured over a wide range of stress conditions. Using the proposed model, an accelerated method for estimating 10 year lifetime is presented. This method does not require a-priori knowledge of parameters and uses a combination of voltage ramp and constant voltage measurements to estimate model parameters with the total measurement time <; 1 hour. Using these extracted parameters and the model equations, 10 year lifetimes are estimated at different stress voltages.