Degradation in TDDB of Cu/low-k test structures due to field interaction between adjacent metal lines

In this paper, small area test structures were used to study the effect of field interaction between neighboring fingers of the test structures. Time dependent dielectric breakdown tests were performed on the test structures. It was determined that the electric field between adjacent fingers, and not only the electric field between the cathode and anode, has an impact on the breakdown lifetime of the low-k dielectric.