Method of manufacture of a thermoelastic bend actuator using PTFE and corrugated copper ink jet printer

• US 6,416,679 B1
• Filed: 07/10/1998
• Issued: 07/09/2002
• Est. Priority Date: 07/15/1997
• Status: Expired due to Fees

• Current Assignee: Zamtec Limited (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Gulakowski, Randy
• Assistant Examiner(s): Ahmed, Shamim
• Application Number:
  US09/112,771
• Time in Patent Office: 1,460 Days
• Field of Search: 216/27, 347/54, 347/55, 347/56
• US Class Current: 216/27
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/1626 etching
• CPC Class Codes: B41J 2/1628 dry etching
• CPC Class Codes: B41J 2/1629 wet etching
• CPC Class Codes: B41J 2/1631 photolithography
• CPC Class Codes: B41J 2/1632 machining
• CPC Class Codes: B41J 2/1635 dividing the wafer into individual chips
• CPC Class Codes: B41J 2/1639 sacrificial molding
• CPC Class Codes: B41J 2/1642 thin film formation by CVD [chemical vapor deposition]
• CPC Class Codes: B41J 2/1643 thin film formation by plating
• CPC Class Codes: B41J 2/1645 thin film formation by spincoating
• CPC Class Codes: B41J 2/1646 thin film formation by sputtering
• CPC Class Codes: B41J 2/1648 Production of print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/16585 for paper-width or non-reciprocating print heads
• CPC Class Codes: B41J 2/17596 Ink pumps, ink valves
• CPC Class Codes: B41J 2002/041 Electromagnetic transducer
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G06K 1/121 by printing code marks applying code marks to labels B65C9/46; marking or coding completed packages B65B61/26
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1417 : 2D bar codes
• CPC Class Codes: G11C 11/56 : using storage elements with more than two stable states represented by steps, e.g. of voltage, current, phase, frequency
• CPC Class Codes: H04N 23/00 : Cameras or camera modules comprising electronic image sensors; Control thereof
• CPC Class Codes: H04N 5/2628 : Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation

Abstract

A method of manufacturing an ink jet printhead the method including the step of depositing a sacrificial material on a substrate and etching the sacrificial material to form a plurality of ink chambers on the substrate, with each ink chamber having an ink ejection port. A thermal expansion material and a conductive material are deposited and etched to form a thermal actuator in each ink chamber. Each thermal actuator comprises an electrical heater element of the conductive material, positioned in the thermal expansion material, the thermal expansion material having a coefficient of thermal expansion which is such that the thermal expansion material is capable of expansion upon heating by the electrical heater element. The heater element is positioned in the thermal material so that such expansion of the thermal expansion material results in displacement of the thermal actuator with respect to the ink ejection port.

Claims

1. A method of manufacturing an ink jet printhead, the method comprising the steps of:

depositing a sacrificial material on a substrate and etching the sacrificial material to form a plurality of ink chambers on the substrate, with each ink chamber having an ink ejection port; and

depositing a thermal expansion material and a conductive material, capable of being resistively heated, on the substrate so that the conductive material is positioned in the thermal expansion material;

etching the conductive material and the thermal expansion material to form a thermal actuator having a free end in each chamber, so that each thermal actuator comprises an electrical heater element of the conductive material, positioned in the thermal expansion material, the thermal expansion material having a coefficient of thermal expansion which is such that the thermal expansion material is capable of expansion upon heating by the electrical heater element, the step of depositing the thermal expansion material and the conductive material being carried out so that the heater element is positioned in the thermal expansion material such that expansion of the thermal expansion material results in displacement of the free end of the thermal actuator with respect to the ink ejection port.

2. A method as claimed in claim 1, wherein the substrate comprises a silicon wafer.

3. A method as claimed in claim 1, wherein the thermal expansion material comprises polytetrafluoroethylene.

4. A method as claimed in claim 1, wherein the heater elements comprise copper.

5. A method as claimed in claim 1, further comprising the step of connecting the heater elements to integrated drive electronics for providing the heater elements with an electrical power supply.

6. A method as claimed in claim 5, further comprising the step of forming the integrated drive electronics with a CMOS process.

7. A method as claimed in claim 1, wherein each thermal actuator is formed with the steps of:

depositing a layer of sacrificial material on the substrate;

depositing a first layer of the thermal expansion material;

depositing, exposing and developing a gray-scale mask layer on the layer of the thermal expansion material;

etching the gray-scale mask layer and the layer of the thermal expansion material, wherein etch rates for the mask material and for the thermal expansion material are substantially the same, so that a corrugated pattern is transferred onto the first layer of the thermal expansion material;

depositing a layer of the conductive material onto the corrugated first layer of the thermal expansion material; and

depositing a second layer of the thermal expansion material on the conductive material so that each heater element is embedded in the thermal expansion material.

8. A method as claimed in claim 7, further comprising the step of planarizing the second layer of the thermal expansion material.