Ink jet printhead that incorporates an etch stop layer
View Patent ↗An ink jet printhead chip that is manufactured in accordance with an integrated circuit fabrication technique includes a wafer substrate that defines a plurality of nozzle chambers as a result of an etching process. An etch stop layer is positioned on a front side of the wafer substrate so that portions of the etch stop layer define a roof wall for each nozzle chamber, each said portion defining at least one ink ejection port, also a result of an etching process carried out on each portion. A plurality of actuators are arranged on a back side of the wafer substrate, each actuator being operatively positioned relative to each respective nozzle chamber to eject ink from the nozzle chambers.
1. A method of manufacturing an ink jet printhead, the method comprising the steps of:
depositing a layer of etch stop material on a front side of a wafer substrate;
etching the wafer substrate up to the etch stop material to define a plurality of nozzle chambers and so that portions of the etch stop layer define roof walls for respective nozzle chambers;
depositing and etching a plurality of actuator layers on the wafer substrate, one of the plurality of actuator layers being a layer of actuator material, the layer of actuator material being etched to define separate ejection and refill actuators for each nozzle chamber; and
etching each said portion of the etch stop layer to form at least one ink ejection port in each said portion.
2. A method as claimed in claim 1 , wherein another of the plurality of actuator layers is a drive circuitry layer which is deposited on a back side of the wafer substrate.
3. A method as claimed in claim 2 , wherein the actuator defining step includes fabricating, with integrated circuit fabrication techniques, the actuators so that each actuator is electrically connected to the drive circuitry and is operatively positioned with respect to each nozzle chamber.