Fig. 1: Schematic view of the principle of ice printing process.
From: Inkjet printing-based fabrication of microscale 3D ice structures

a Schematic view of the ice printing setup. b Operating principle of ice printing technology. The temperature of the substrate is controlled by Peltier coolers, which are powered with a direct current (DC) voltage source. The droplets are provided locally from the piezoelectric nozzles, thereby confining the freezing process for local ice structure patterning. The size of the droplets is controlled by the air pressure and the voltage pulse signal. c–e Layer-by-layer printing process of a 3D structure