Inkjet printheads

• US 6,588,882 B2
• Filed: 04/16/2001
• Issued: 07/08/2003
• Est. Priority Date: 07/15/1997
• Status: Expired due to Fees

• Current Assignee: Memjet Technology Ltd. (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): Do, An H.
• Application Number:
  US09/835,457
• Publication Number:
  US 20020033863A1
• Time in Patent Office: 813 Days
• Field of Search: 347/20, 347/40, 347/44, 347/54, 347/68, 216/27
• US Class Current: 347/54
• CPC Class Codes: B41J 2/04505 aiming at correcting alignment
• CPC Class Codes: B41J 2/04516 preventing formation of satellite drops
• CPC Class Codes: B41J 2/04518 reducing costs
• CPC Class Codes: B41J 2/0452 reducing demand in current or voltage
• CPC Class Codes: B41J 2/04528 aiming at warming up the head
• CPC Class Codes: B41J 2/04541 Specific driving circuit
• CPC Class Codes: B41J 2/04543 Block driving
• CPC Class Codes: B41J 2/04553 detecting ambient temperature
• CPC Class Codes: B41J 2/04563 detecting head temperature; Ink temperature
• CPC Class Codes: B41J 2/04565 detecting heater resistance
• CPC Class Codes: B41J 2/0457 Power supply level being detected or varied
• CPC Class Codes: B41J 2/04571 detecting viscosity
• CPC Class Codes: B41J 2/04585 controlling heads based on thermal bent actuators
• CPC Class Codes: B41J 2/0459 Height of the driving signal being adjusted
• CPC Class Codes: B41J 2/04591 Width of the driving signal being adjusted
• CPC Class Codes: B41J 2/04593 Dot-size modulation by changing the size of the drop
• CPC Class Codes: B41J 2/04598 Pre-pulse
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/1623 bonding and adhesion
• 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 2202/03 : Specific materials used
• CPC Class Codes: B41J 3/445 : Printers integrated in other types of apparatus, e.g. printers integrated in cameras

Abstract

An inkjet printhead having a series of nozzles for the ejection of ink wherein each said nozzle has a rim formed by the deposition of a rim material layer over a sacrificial layer and a subsequent planar removal of at least said rim material layer so as to form said nozzle rim.

Claims

1. An inkjet printhead comprising:

a plurality of nozzle chambers each having an ink ejection aperture in one wall thereof and an actuating aperture in a second wall thereof; and

a moveable ink ejection paddle located within the nozzle chamber and moveable under the control of an external thermal actuator through the actuator interconnection aperture for the ejection of ink out of the ink ejection aperture;

wherein the external actuator being covered by a protective covering shell around the operational portions of the actuator, spaced apart from the actuator.

2. An inkjet printhead as claimed in claim 1 wherein said protective covering shell is formed simultaneously with the formation of other portions of said inkjet printhead.

3. An inkjet printhead as claimed in claim 2 wherein said protective covering shell is formed simultaneously with said walls of said nozzle chamber.

4. An inkjet printhead as claimed in claim 2 wherein said protective covering shell is formed by depositing and etching of a sacrificial material layer followed by deposition and etching of an inert material layer forming said protective covering shell.

5. An inkjet printing arrangement as claimed in claim 2 wherein said external actuator comprises a thermal bend actuator.

6. A method of forming an inkjet printhead on a substrate, said method including:

providing said substrate in which is formed an electrical driver circuitry made up of layers of conductive, semi-conductive and non-conductive materials for the control of said inkjet printhead;

forming on said substrate at least one nozzle chamber having an ink ejection aperture in a wall thereof and ink ejection means to eject the ink from said aperture;

wherein portions of at least one of said layers of said substrate are utilized as a sacrificial material layer in the formation of at least part of said ink ejection means; and

wherein a moveable ink ejection paddle located within the nozzle chamber and moveable under the control of an external thermal actuator through the actuator interconnection aperture for the ejection of ink out of the ink ejection aperture;

wherein the external actuator being covered by a protective covering shell around the operational portions of the actuator, spaced apart from the actuator.

7. A method as claimed in claim 6 wherein said ink ejection means comprises a moveable ink ejection paddle within said nozzle chamber, moveable under the control of an actuator for the ejection of ink from said aperture.

8. A method as claimed in claim 7 wherein said actuator comprises a thermal actuator.

9. A method as claimed in claim 7 wherein said actuator is located external to said nozzle chamber and is interconnected with said ink ejection paddle through an actuating aperture formed in a second wall of said nozzle chamber.

10. A method as claimed in claim 6 wherein said sacrificial material layer comprises portions of a conductive layer of said electrical drive circuitry.

11. A method as claimed in claim 10 wherein said electrical drive circuitry comprises a Complementary Metal Oxide Semiconductor (CMOS) process.

12. A method as claimed in claim 10 wherein said sacrificial material layer comprises a CMOS metal layer.