Copper pumping of through silicon vias in reliability test

Through silicon via (TSV) based 2.5D and 3D integration technology is regarded as the most promising enabling technology for next generation system integration. One of the concerns associated with TSV is the reliability issue of the TSV based devices due to the CTE mismatch between silicon and copper. In this paper, we report the reliability assessment of Cu pumping treated at different annealing conditions. The pumping of TSVs having a diameter of 10 μm and a depth of 100 μm has been characterized by white light optical profiler. According to the TC, HTS and HAST test results, higher annealing temperature is beneficial to control the Cu pumping and improve the TSV reliability.