Creep properties of low-temperature sintered nano-silver lap shear joints

As a potential alternative to conventional solders and adhesive films, low-temperature sintered nano-silver paste, as a result of its high thermal and electrical conductivity (240 W m−1 K−1 and 4.1×107 S m−1, respectively) and high melting temperature (961 °C), can be used for connecting chips that require high temperature operation and high heat dissipation ability. In the present work, a number of creep tests were carried out to study the effect of stress and temperature on the creep behavior of low-temperature sintered nano-silver lap shear joints. The steady-state creep flow behavior of the joints was discussed. In general, the creep shear strain rate increased as the applied stress and ambient temperature increased. When the creep strain rate was described by the Arrhenius power-law model, we found that the stress exponent and activation energy were temperature dependent and stress dependent, respectively. A modified power-law model with a temperature-dependent stress exponent and stress-dependent activation energy was proposed to describe accurately the creep flow of the sintered lap shear joints.