Micro-electromechanical fluid ejection device with control logic circuitry

A micro-electromechanical fluid ejection device that comprises

• a substrate;
• a nozzle chamber wall and a roof wall that are positioned on the substrate to define a nozzle chamber and an ink ejection port in the roof wall, a fluid being receivable in the nozzle chamber;
• an elongate actuator arm having a fixed end portion that is fast with the substrate and a free end portion that is spaced from the substrate, the elongate actuator arm incorporating a heating circuit that is connectable to a power supply to heat the actuator arm, at least a portion of the actuator arm being of a material having a coefficient of thermal expansion which is such that the material is capable of thermal expansion to do work, the heating circuit being positioned to generate differential thermal expansion and contraction when heated and subsequently cooled to cause reciprocal displacement of the free end portion of the actuator arm;
• a fluid ejection member that is fast with the free end of the elongate actuator arm to be positioned in the nozzle chamber such that said displacement of the free end portion of the actuator arm results in the ejection of fluid from the ink ejection port;
• and
• control logic circuitry positioned on the substrate along an elongate region defined on the substrate and interposed between the actuator arm and the substrate, the control logic circuitry being connected to the heating circuit to enable and disable the power supply according to a control signal received by the control logic circuitry.