Shape controllable micro-nozzle fabrication

A novel fabrication method involving two-step sequential backside exposures utilizing Fraunhofer diffraction is developed in this work to overcome some of the limitations of the current micro-nozzle fabrication techniques in controlling the shape and the size of micro-nozzles. Shape and size of the fabricated micro-nozzles are compared with simulation results. Micro-nozzles with tip diameters varying from 0 to 158.1 μm and the base diameter varying from 167.2 to 360 μm are fabricated simultaneously side-by-side on the same substrate by varying the total exposure dosage from 3 to 6 J/cm2 utilizing multiple backside exposures through designed circular aperture and zone plate masks.