Failure mode study of inappropriate type design to evaluate reliability on TU geometry

In this study, we found that inappropriate TU (top Cu metal line) geometry design induced product reliability failures issue. The TU geometry, having poor compatibility with wafer test probe issue, couldn't withstand the stress of wafer test probe resulting in fractures. Due to the inappropriate TU geometry design had major disadvantages in circuits characteristics. Reliability estimations exhibited different performances for these two TU geometries.