Low voltage IMD-TDDB lifetime model for advanced future logic technology nodes

Scaled advanced technologies with its narrow metal line spaces are prone to very wide variation. Therefore, having an accurate IMD-TDDB lifetime projection as the upcoming technologies shrink in dimensions is critical. It was reported previously that the Weibull shape parameter p is improved at low field stress (use condition) compared to higher fields (stress condition) in regard to field dependence model approach (E, a/E model) [1-2]. In this paper, we show that the P of IMD-TDDB improves as stress field or voltage is reduced through simulation by using the space data obtained from in-line SEM measurement This is further verified by the long-term (up to 8 months of package level) IMD-TDDB experimental data from various technology nodes with 80-100nm pitch. For the voltage projection, we also show that power-law shows better fit to the long term data. The study is highly useful for developing and qualifying the technology node beyond 14nm.