Non-metallurgical bonding technology with super-narrow gap for 3D stacked LSI

The chip-stacking technologies with the thin devices in hyperfine pitch realize both of the strong demands for the high-speed signal transmission and the high-density packaging. The results of the experiments on the non-metallurgical bonding and encapsulation with nonconductive particle paste (NCP) are introduced. It realizes void-free encapsulation of under 10-μm-thick gap, small warpage of 50-μm-thick chip, and ohmic contact of all of 1844 bumps in 20-μm-pitch. Additionally, it is found the flatness of chip backside is achieved sufficient level for the thin chip stacking process with hyper fine pitch interconnection.