Copper nanoplates based conductive paste as die attachment materials for power semiconductor device package

As novel high temperature interconnect materials, copper nanomaterial based conductive pastes have received more and more attention due to their good electrical conductivity, thermal conductivity and reliability after sintering. Currently, the most widely used copper materials in the copper paste is mainly copper nanoparticles. In this work, we developed an innovative Cu nanoplate with a diameter of about 400 nm and a thickness of about 80 nm. Then we evaluate the applications of Cu nanoplates based paste as a low temperature interconnect material and investigated the effect of sintering parameters (sintering time, sintering temperature) on the final shear strength of joints. The results show that a high shear strength about 29 MPa can be achieved at the sintering temperature of 250 °C and applied pressure of 10 MPa in the vacuum environment, which was due to that copper nanoplates have more contact surface than copper nanoparticles and are more conducive to low temperature sintering. These results indicate that the copper nanoplate is a good electrical filler for high temperature conductive paste applications.