Numerical and experimental investigations on intense pulsed light sintering of silver nanoparticle inks for printed electronics

Abstract

Intense pulsed light (IPL) sintering has the advantages of high efficiency and selective heating for silver nanoparticles (AgNPs) inks, which could be widely used in printed electronics. In this contribution, the heat transfer and diffusion mechanisms of AgNPs during IPL sintering are quantitatively investigated with a mathematic model combined transient heat transfer and molecular dynamics (MD) method and experiments. The results show that only 51.522% of the IPL radiation energy is absorbed by the AgNPs. During IPL sintering, the temperature of AgNPs rises significantly, whereas the temperature of polyamide substrate keeps almost unchanged, demonstrating that IPL is feasible for thermal-sensitive substrates. The MD modeling results show that sintering neck between AgNPs forms and grows rapidly at the beginning of sintering, then remains relative stable. Accordingly, the electrical resistivity of the AgNPs drops rapidly to a stable value. In addition, the effects of IPL sintering parameters are studied and the results show that increasing IPL energy and reducing IPL duration could increase the sintering performance of AgNPs inks. Finally, an antenna is fabricated using AgNP inks and IPL sintering technology. The experimentally measured performance of the antenna agrees well with the theoretical analysis. Our simulation and experimental results demonstrate that IPL is suitable for sintering of AgNPs inks for flexible electronics.