Impact of NBTI-driven parameter degradation on lifetime of a 90nm p-MOSFET

NBTI has emerged as a major reliability concern for the electrical stability of advanced CMOS technology. We report an experimental and simulation study for the NBTI mechanism in a high-performance p-MOSFET. Various stress experiments were performed in order to analyze the degradation of the key device parameters, V_T and I_Dsat. The presently leading reaction-diffusion (R-D) model is used to study the interface trap generation based on the diffusion and accumulation of released hydrogen in the gate oxide. The long-time degradation was simulated in order to estimate the NBTI lifetime which depends on the applied gate voltages and frequencies. The lifetime extension under higher frequency operation was analyzed at a typical supply voltage of 1.45V with a tolerance of ±50mV. An unexpected long lifetime extension between six times and twenty times of the DC lifetime was found for an operation with a 10MHz gate signal.