Patent ID: 7441870

Claim:
A liquid-ejection integrated circuit device that comprises a substrate that defines a plurality of liquid inlet channels; a drive circuitry layer positioned on the substrate; a plurality of nozzle chamber structures positioned on the substrate, each nozzle chamber structure defining a nozzle chamber in communication with a respective inlet channel and a liquid ejection port and incorporating a movable liquid ejection member that serves to eject liquid from the liquid ejection port when displaced; a micro-electromechanical actuator connected to the drive circuitry layer to receive drive signals and operable on the movable liquid ejection member to displace the liquid ejection member; and a nozzle guard mounted on the substrate and defining a plurality of apertures in alignment with respective liquid ejection ports, the nozzle guard and the substrate having substantially the same coefficient of thermal expansion to inhibit the apertures moving out of alignment with the liquid ejection ports as a result of heating of the substrate.