NBTI Mitigation in Microprocessor Designs

Negative-Bias Temperature Instability seriously affects nanoscale circuits reliability and performance. Continuous stress and increasing operating temperatures lead to device degradation and long-term system unavailability. The opportunity to optimize the duty-cycle of the stress/recovery phases to reduce Vth degradation leads to innovative research of reliability-oriented resources allocation at architectural level. This work explores the impact of different allocation strategies on the processor degradation, through a novel estimation methodology. Experimental results show that the proposed NBTI-aware allocation strategy can guarantee from 10% and up to 30% lower degradation compared to classical strategies, under different operating scenarios and under process variability.