Deposition behavior optimization of on-demand tin droplet with gravity based on piezoelectric micro-jet

•Analysis of deformation and heat transfer of tin droplet with theoretical model.•Horizontal ejecting of the droplet in demand by a piezoelectric micro-jet device.•Effect of gravity on dynamic spreading and solidification studied with simulation.•Temperature effect of droplet and substrate on heat transfer and solidification.•Suppressing tilt angle of droplet by increasing velocity and solidification time.