Soft-Error Vulnerability of Sub-100-nm Flip-Flops

The soft-error vulnerability of flip-flops has become an important factor in IC reliability in sub-100-nm CMOS technologies. In the present work the soft-error rate (SER) of a 65-nm flip-flop has been investigated with the use of alpha-accelerated testing. Simulations have been applied to study the flip-flop SER sensitivity in detail. Furthermore, an easy-to-use approach is presented to make an accurate estimation of the contribution of flip-flops to the SER of an IC. The method is applicable to frequencies well below 1 GHz. The approach is based on a set of expressions for the timing vulnerability factor (TVF) of the master and slave latches of the flip-flop. With this approach it is possible to make an accurate estimation of the flip-flop SER parameters.