Method of forming stacked dies

摘要

The formation of through silicon vias (TSVs) in an integrated circuit (IC) die or wafer is described in which the TSV is formed in the integration process prior to metallization processing. TSVs may be fabricated with increased aspect ratio, extending deeper in a wafer substrate. The method generally reduces the risk of overly-thinning a wafer substrate in a wafer back-side grinding process typically used to expose and make electrical contacts to the TSVs. By providing deeper TSVs and bonding pads, individual wafers and dies may be bonded directly between the TSVs and bonding pads on an additional wafer.