Development of Metallization Process for Fine Pitch TSV

Defect-free TSV fabrication process for Cu filling of $1.0 \mu \mathrm{m}$ and $1.5 \mu \mathrm{m}$ diameters with an aspect ratio of 7 and 6 is studied. To improve barrier/seed layer step coverage, TSV profile with scallop free with slight taper was developed, and an electroplating process was for solid TSV Cu filling. Defect-free TSV filling can be achieved for TSV with $1.0 \mu \mathrm{m}$ and $1.5 \mu \mathrm{m}$ diameters.