Large-scale synthesis of silver nanoparticles by aqueous reduction for low-temperature sintering bonding

Abstract

Silver nanoparticles with average diameter of 22.4 nm were prepared by aqueous reduction method for low-temperature sintering bonding application. The reaction temperature and PVP concentration, which are the influential factors of nanoparticle characteristics, were investigated during reduction process. In our research, monodispersity of nanoparticles was remarkably improved while unfavorable agglomeration was avoided with the AgNOPVP mass ratio of 1: 4 at the reaction temperature 30°C. Besides, copper pads were successfully bonded using sintering paste employing fresh silver nanoparticles with diameter of 2035 nm at 200°C. In addition, after morphology of the bonding joint was analysed by scanning electron microscope (SEM), the porous sintering characteristics were confirmed. © 2014 Qiu Xiliang et al.