Abstract
The metallic nanoparticle paste is receiving great interests recently because it is a potential interconnect material which can perform joining at low temperature and serves at high temperature. The nano-Ag paste and nano-Cu paste have been the hot areas of research, whereas the high cost and low resistance of electrochemical migration of the former and the relatively low anti-oxidation property of the latter limit their applications. In this study, Ag-Cu alloy nanoparticles with the size of 20–50 nm were synthesized with glucose as the reducing agent and NaOH as accelerator. The Ag-Cu nanoparticle paste showed no oxidation after sintering up to 350°C in the air, indicating that the antioxidant capacity was superior to that of the mechanically mixed Ag nanoparticles and Cu nanoparticles. In addition, the electrochemical migration resistance of the sintered Ag-Cu alloy pastes was better than that of the Ag nanoparticle paste. This paste can be used to effectively bond silver-plated copper bulks with maximum shear strength of 35 MPa.
