Effect of holding time on the self-joining of silicon nitride

Reliable Si₃N₄/Si₃N₄ joints were obtained using Cu{single bond}Pd{single bond}Ti as filler alloy. The effect of holding time on interfacial microstructure and bonding strength of the joints was investigated. All the joints consist of continuous reaction layer (fine-grain TiN), discontinuous reaction layer (coarse-grain TiN), Cu-based solid solution and reaction products. Prolonged exposure to the elevated temperature causes the thickness of the discontinuous reaction layer to increase, due to the coarsening of TiN grains. And the amount of Pd{single bond}Si phase increases instead of Ti{single bond}Si phase. With the increase of holding time, the bonding strength of the joints decreases. The formation of a reaction layer with a suitable thickness promotes the improvement of bonding strength of joints.