Long term accelerated ageing of an ASIC dedicated to cryptographic application

This paper deals with data analysis of long term (2 years) accelerated stress test of a 65 nm ASIC dedicated to cryptographic applications. Several stress conditions have been applied by combining both thermal and electrical overvoltage stresses. At the end of the ageing test, frequency drifts analysis indicates the presence of NBTI. Two statistical calculation methods have been considered in estimating the mean or median time to failure, each one relying on a different failure criterion. We confirm reliability of 65 nm technologic node even in complex architecture.