In-tandem deposition and sintering of printed gold nanoparticle inks induced by continuous Gaussian laser irradiation

By employing continuous Gaussian laser irradiation in tandem with a specifically designed drop-on-demand jetting system, nanoparticle inks were printed and sintered on glass substrate. A toluene solvent is employed as the carrier of gold nanoparticles possessing a lower melting temperature than that of bulk gold. Marangoni flow due to radial surface tension gradient combined with a moving substrate displaces nanoparticle ink in front of and around the laser spot. Experiments were carried out changing incident laser power, focused beam waist, and translation speed, and resulting phenomena at different conditions were explained. Strong coalescence occurred from 9000-14000 W/cm(2), and a gold line with 8 mum of width was demonstrated.