Conference Paper

Estimation of NBTI Degradation using IDDQ Measurement

Purdue Univ., West Lafayette, IN;
DOI: 10.1109/RELPHY.2007.369861 Conference: Reliability physics symposium, 2007. proceedings. 45th annual. ieee international
Source: IEEE Xplore

ABSTRACT Negative bias temperature instability (NBTI) has emerged as a major reliability degradation factor in nano-scale CMOS technology. In this paper, we analyze the impact of NBTI degradation in both the maximum operating frequency (fMAX) and the total standby leakage current (IDDQ) of digital CMOS circuits. Our analysis shows that due to NBTI, both fMAX and IDDQ reduce with time with a fix exponent of 1/6 (~t1/6). Based on this analysis, we develop temporal fMAX-IDDQ model and apply it to several ISCAS'85 benchmark circuits designed using BPTM 70nm file. Results show that fMAX and IDDQ can reduce by more than 8% and 30% in 3 years operation time, respectively. Furthermore, we show that fMAX and IDDQ degradations are highly correlated throughout the operating lifetime, and using this fact, one can avoid expensive fMAX testing and predict fMAX degradations as a function of IDDQ measures.

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