Conductivity of silver paste prepared from nanoparticles

Conductivity of silver pastes using nanoparticles was investigated with sintering temperatures. Nano-sized silver particles with 50-100 nm in size were prepared by chemical reduction method. Silver pastes composed of nanoparticles (80 wt%), Pb-free frit (1.0 wt%) and organic vehicle (19 wt%) were screen printed on alumina substrates and sintered at temperatures ranging from 250 to 450 degrees C. As increasing the sintering temperatures, densification and grain growth were observed. When sintered at 400 degrees C, a distinct decrease in film thickness and a sharp increase in the rate of shrinkage took place, which in turn densification was developed at this temperature. With sintering temperatures, electrical resistivity of the films decreased due to denser microstructure and the films sintered at 450 degrees C showed 4.11 mu Omega cm which can be compatible for various electronic devices. (C) 2007 Elsevier B.V. All rights reserved.