Low-temperature MOD assisted sintering of Ag nanoparticles for power device die-attach

With the wide application of third-generation semiconductor in power devices, the development of the new material that can satisfy the high-temperature service of die-attach joint has become a significant challenge. Silver has attracted extensive attention for high thermal and electrical conductivity. However, the industrial application of silver has been restricted due to its high melting temperature. In this paper, a novel Ag nanoparticle paste assisted with MOD (metal organic decomposition) was prepared, and a low-temperature Ag-Ag bonding with high strength was obtained. Silver oxalate is synthesized as a silver precursor and complexed with ethylenediamine to form a silver ammonia complex as a metal organic source. The active metal organic source with low decomposition temperature was employed as a bridge among the commercial silver nanoparticle. After sintering at 150 °C for 30 min under certain pressure, the shear strength of sintered bonding joints can reach 17 MPa. The fracture and cross-sectional microstructures of bonded joints exhibited obvious ductile characteristics and compact structure. These results suggest the silver paste with MOD is prone to sinter at a low temperature and can fulfill the requirements of die-attach materials for power device packaging.