Development of nanocomposite pastes for low-temperature low-pressure bonding

In this study, newly developed Cu-Ag composite pastes consisted of Ag nanoparticles, Ag submicron particles and copper formate were adopted for low-temperature low-pressure bonding. Joints between the substrates of Cu, Ni/Au, and Ag finishes can be well formed at a temperature down to 160°C under a load pressure of 1.6MPa. The joints with Cu substrates thus bonded possess bonding strength of 18.0 MPa and those with Ag surface finish exhibit shear strength of 23.3 MPa. The electrical resistivity of the sintered structure thus obtained is 41.7 μΩ-cm.