Advancements in Metal Passivation Process for Low-Temperature Cu-Cu Direct Bonding

With the emergence of 3D packaging technology, Cu-Cu direct bonding is significant attention. In this paper, we investigated metal passivation layer for low-temperature Cu-Cu direct bonding. We analyzed the characteristics of the Ti metal passivation layer and investigated the variations in diffusion process based an different deposition conditions. Additionally, we conducted various types of metal passivation bonding to compare their diffusion characteristics.