Patent ID: 7229153

Claim:
A printhead integrated circuit which comprises a substrate; drive circuitry positioned on the substrate; a plurality of nozzle chamber structures positioned on the substrate, each nozzle chamber structure defining a nozzle chamber and an ink ejection port in fluid communication with the nozzle chamber; and a plurality of micro-electromechanical actuators positioned on the substrate, each actuator comprising opposed activation members extending from a substrate and defining a gap therebetween, the activation members being fast with each other and one of the activation members defining a heating circuit connected to the drive circuitry layer to be heated and to expand and subsequently contract on receipt of an electrical pulse from the drive circuitry such that the activation members undergo differential thermal expansion causing displacement of the activation members relative to the substrate; and an actuator arm fast with the activation members to be displaceable with the activation members, wherein a heat sink is connected to said one of the activation members to enhance heat dissipation on termination of the electrical pulse.