Solid-State-Diffusion Bonding for Wafer-Level Fine-Pitch Cu/Sn/Cu Interconnect in 3-D Integration

Low-temperature Cu/Sn/Cu solid-state-diffusion (SSD) bonding has been investigated in this paper. Twenty-micrometer fine-pitch bumps with daisy-chain and Kelvin structures were fabricated by high-efficiency and low-cost electroplating process. Before bonding, the bump surface was treated with Ar(5% H2) plasma. Wafer-level bonding was performed with a… CONTINUE READING