A Low-Cost Passivation for Low Temperature Cu-Cu Bonding Using PVD-Deposited Cu3N

PVD-deposited Cu3N has been demonstrated for Cu-Cu bonding as a low-cost passivation material. exhibits stability at room temperature but undergoes decomposition upon heating, making it an attractive candidate Cu passivation. XRD analysis reveals that the of primarily occurs within range 200250. Cu3N-Cu3N bonding, relying on reaction, is successfully demonstrated, and TEM confirms presence grains interface. Moreover, using well. The capability low temperatures found to be influenced by thin film properties Cu3N. For wafer level N2 flow rate during deposition requires careful adjustment balance antioxidation outgassing phenomenon. chip phenomenon poses no significant issue. By demonstrating potential material, this study suggests promising method achieving lower requirements in through properties.