Sintering of Inkjet-Printed Silver Nanoparticles at Room Temperature Using Intense Pulsed Light

Abstract

Intense pulsed light (IPL) was used to sinter printed silver nanoink patterns consisting of 20-nm to 40-nm silver nanoparticles dispersed in diethylene glycol (DEG). Three consecutive pulses at 50 J/cm(2) in less than 30 ms was sufficient to adequately sinter silver nanoink patterns for printed electronics without degradation of the substrates. This is an exceptionally short time compared with that of the conventional thermal sintering process. On the sintered conductive silver patterns, neck-like junctions between nanoparticles were observed using scanning electron microscopy (SEM). The melting temperature, 194.1A degrees C, of silver nanoparticles was found using differential scanning calorimetry (DSC). Also, x-ray diffraction (XRD) was used to find the grain size of the printed silver nanoink patterns. The IPL-sintered silver pattern had a grain size of 86.3 +/- A 7.2 nm. From this work, it was found that the IPL-sintered silver pattern had a low resistivity of 49 +/- A 3 n Omega m, which is low enough to be used for printed electronics.