Successful void free gap fill of 3µm, high AR via middle, Through Silicon Vias at wafer level

This paper presents challenges encountered in the fabrication of high aspect ratio (AR) via middle, Through Silicon Vias (TSV), of 3μm top entrant critical dimension (CD) and 50μm depth. Higher AR TSV integration is explored due to the lower stress influence of TSVs observed in adjacent CMOS devices.