3D interconnection process development and integration with low stress TSV

Abstract

The 3 D interconnect technology with Thru Silicon Via (TSV) have gained tremendous advancement in recent years. Final adoption of TSV technologies requires a robust and cost competitive TSV processes. Sidewall plated TSV with polymer filling can reduce half of total process steps from TSV copper (Cu) seed deposition to front-vial expose. TSV plating time can be reduced ~60% for sidewall plated TSV with polymer filling. Costly Cu removal process through chemical mechanical polishing (CMP) can be skipped in sidewall plated TSV with polymer filling process. Wafer warpage and bow for sidewall plated TSV with polymer filling were shown to be ~70% and ~94%, respectively lower than solid Cu filled TSV. Thermal-mechanical simulation show 20% and 42% reduction of shear and bending stress respectively in the case of sidewall plated TSV with polymer filling.