Bubble jet printhead with integrated polyimide nozzle plate

This paper reports for the first time on a new 1/3 inch thermal bubble jet printhead with integrated nozzle plate. The printhead is a combination of a standard printhead substrate with a new three-dimensional structured polyimide nozzle plate avoiding a three layer assembly known from other commercial printheads. The 50 μm thick nozzle plate contains the fluidic channels and 208 nozzles with minimum lateral dimensions of 10 μm. The misalignment of the two laser structured layers has proved to be less than 1 μm. The nozzle plate is assembled with the substrate using a 3 μm adhesive layer with an alignment accuracy of 3 μm. The integrated nozzle plate leads to a better control of the printhead geometry and saves one processing step in production. Fully three dimensional computational fluid dynamics (CFD) simulations have been performed to investigate the effect of misalignments, the thickness of the adhesive layer and heater geometry. The agreement between simulation and experiment is better than 5%.