Impact of Bias Temperature Instability on Soft Error Susceptibility

In this paper, we address the issue of analyzing the effects of aging mechanisms on ICs' soft error (SE) susceptibility. In particular, we consider bias temperature instability (BTI), namely negative BTI in pMOS transistors and positive BTI in nMOS transistors that are recognized as the most critical aging mechanisms reducing the reliability of ICs. We show that BTI reduces significantly the critical charge of nodes of combinational circuits during their in-field operation, thus increasing the SE susceptibility of the whole IC. We then propose a time dependent model for SE susceptibility evaluation, enabling the use of adaptive SE hardening approaches, based on the ICs lifetime

Accurate linear model for SET critical charge estimation

In this paper, we present an accurate linear model for estimating the minimum amount of collected charge due to an energetic particle striking a combinational circuit node that may give rise to a SET with an amplitude larger than the noise margin of the subsequent gates. This charge value will be referred to as SET critical charge (Q-SET}). Our proposed model allows to calculate the Q-SET} of a node as a function of the size of the transistors of the gate driving the node and the fan-out gate(s), with no need for time costly electrical level simulations. This makes our approach suitable to be integrated into a design automation tool for circuit radiation hardening. The proposed model features 96% average accuracy compared to electrical level simulations performed by HSPICE. Additionally, it highlights that Q-SET} has a much stronger dependence on the strength of the gate driving the node, than on the node total capacitance. This property could be considered by robust design techniques in order to improve their effectiveness. © 2006 IEEE