Modeling soft error effects considering process variations

This paper addresses the aggregated effects of two types of variations that contribute to the reliability degradation. The first one is the increasing level of process variation; the second one is one particular type of environmental variation - the radiation-induced soft error. Their simultaneous presence can cause large negative performance impact. We present a statistical approach to model the generation and propagation of a transient soft error inside combinational circuits considering the existence of inter-die channel length variation in CMOS digital circuits. Experiment results have demonstrated that channel length variation can significantly aggravate the soft error effect, which can be accurately evaluated using the proposed methodology.