The effect of silver particle size and organic stabilizers on the conductivity of silver particulate films in thermal sintering processes

Abstract

Herein, we investigated the effect of silver particle size and the type of organic stabilizers on the conductivity and morphology of silver particulate films upon sintering at different temperatures. Four types of silver nanoparticles were prepared via chemical reduction in the presence of three different types of organic stabilizers. These silver nanoparticles, which were different in size, were then fabricated into silver ink pastes, printed to form silver films, and sintered. It was found that the size of the silver nanoparticles was the main factor that influenced the initial decrease in the resistivity of the films; this was accomplished by neck formation between particles. Alternatively, the type of organic stabilizer was the most important factor for determining the final resistivity in the conductive films; this was accomplished by the interconnections of silver nanoparticles via extended neck formation. The amount of organic stabilizers also affected the sintering temperature that was required for the films to be conductive and influenced the final resistivity of the conductive films. The lowest resistivity (2.2 mu Omega cm) was obtained for the film that was prepared using 3.4 nm silver nanoparticles, hexyl amine as a stabilizer, and sintered at 220 degrees C.