Patent ID: 8646875

Claim:
An inkjet printhead comprising: a substrate; an electrostatically actuated diaphragm formed on the substrate; and a nozzle plate mounted to the substrate to define an ink cavity between the substrate and the nozzle plate, the nozzle plate comprising a silicon on insulator structure and a stepped nozzle formed therein, wherein the silicon on insulator structure comprises a silicon dioxide layer arranged between a first layer of silicon and a second layer of silicon, wherein each the first layer of silicon and the second layer of silicon is about 12.5 μm thick and the nozzle plate is about 25 μm in overall thickness, wherein the diaphragm is flexed to apply pressure to ink disposed in the ink cavity to force the ink through the stepped nozzle, and wherein the stepped nozzle comprises: an exit diameter configured to control a mass of an ink drop, wherein the exit diameter is about 25 μm; an entrance diameter configured to control, a speed of the ink drop independently from the mass of the ink drop, wherein the entrance diameter is in a range of about 35 μm to about 50 μm; a first section defined by sloped sidewalls, wherein the entrance diameter is an outer surface of the first section; and a second section defined by sloped sidewalls, wherein the exit diameter is an outer surface of the second section, the first and second sections being aligned.