Low temperature Cu/In bonding for 3D integration

This study represents the results of Cu/In bonding based on solid-liquid interdiffusion (SLID) principle for 3D integration. Fine-pitch interconnects were successfully fabricated at the bonding temperature of 170 degrees C. The final microstructure of the interconnects consists of Cu and Cu/In intermetallic compounds (IMCs) and it is described in detail. The influence of the isothermal storage on the microstructure development is investigated as well.