Room temperature sintering of ag nano-scale particles with drying of the solvent

We successfully developed a new Ag nanoparticle paste which can sinter at room temperature simply by drying solvent of the paste. Very small amount of alkylamine was incorporated into the Ag nanoparticles paste to protect the nanoparticles. By drying at room temperature, Ag nanoparticles are sintered resulting in low resistivity of 4.9times10^-6 Omegam. Necking and coalescence of Ag nanoparticles occur only for a few minutes after drying the solvent. At room temperature, grain of Ag nanoparticles grows gradually for a few days. Heat treatment of the paste can reduce the resistivity effectively. The Ag nanoparticle paste was printed on glass substrates and was heated at 50degC, 100degC and 150degC for various times, respectively. Sintering of nanoparticles was promoted by this heat-treatment. It was observed that Ag nanoparticles grow by absorbing smaller nanoparticles during sintering. By this sintering mechanism, nanoparticles can grow much bigger than uniform sintering mechanism. Since the new paste can be sintered even at room temperature without heat treatment, the paste can expand the versatility of its applications for electronics wiring.