Thermal characteristics of laser sintering and dry-printing silver nanoparticles on thermosensitive substrates

Abstract Inkless electronics printing with in-situ laser sintering coupled with high-velocity argon gas has shown promise when printing on a thermosensitive substrate such as biodegradable and water-soluble papers. This approach has demonstrated an increase in sintering temperature beyond the typical burning threshold of the paper substrate and has potential for other substrates. The degree to which the printing method has increased the durability of these substrates has not yet been quantified. Therefore, this study simulated thermal transients of sintering and printing electrical circuits with pure silver nanoparticles produced in situ with laser ablation and deposited on a paper substrate. The burning threshold of paper and absorptivity of the as-printed nanoparticles were quantified through experimentation. Through simulation, it was found that the printing method could successfully sinter the silver nanoparticles 40 °C above the paper’s typical burning threshold without damaging the paper due to rapid heating and cooling rates, lack of oxygen, and low interaction time. The results show that sintering temperatures up to 27% of the melting temperature of bulk silver can be utilized to successfully print pure silver nanoparticles on paper substrate.