Smart Interface Team

It is important to design the physical and chemical nanostructure of the interfaces to ensure seamless signal and thermal transmission from the FEOL to the BEOL regions. Solid-state debonding would also be key to chip replaceability in future Chiplet Packaging. We have developed hybrid bonding at low temperatures without vacuum using vapor-assisted vacuum ultraviolet (V-VUV) surface modification. In the V-VUV method, a few nm-thick functional bridge layer can be formed on diverse materials, and a limited volume of oxide nanocrystals from the starting materials is spontaneously generated within the bridge Using the V-VUV method, we have improved the reliability of the hybrid interfaces, including their anti-hydrolysis properties. Furthermore, particularly at the Cu-Cu interfaces, the fundamentals of solid-phase chip delamination technology have been established, based on the expansion of CuO nanocrystals due to the spin-lattice coupling effect. In addition, we have demonstrated the tunability of molecular adsorption on semiconductor and metal oxides using this method. This would enable high bondability between novel conductive materials and conventional semiconductor substrates in interconnections for the "beyond 2nm era." We have also demonstrated improved Ag coverage on Cu electrodes to enhance conductivity and an outstanding increase in the sensitivity of a MEMS vapor sensor by modifying the number of adsorbed molecules.