Printhead fabrication method

• US 7,189,334 B2
• Filed: 06/24/2005
• Issued: 03/13/2007
• Est. Priority Date: 10/16/1998
• Status: Expired due to Fees

• Current Assignee: Zamtec Limited (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Norton; Nadine
• Assistant Examiner(s): Tran; Binh X.
• Application Number:
  US11/165,062
• Publication Number:
  US 20050242058A1
• Time in Patent Office: 627 Days
• Field of Search: 216/27, 216/74, 216/77, 216/79
• US Class Current: 216/27
• CPC Class Codes: B05D 2201/00 Polymeric substrate or laminate
• CPC Class Codes: B05D 3/08 by flames
• 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 2/04571 detecting viscosity
• CPC Class Codes: B41J 2/04585 controlling heads based on thermal bent actuators
• CPC Class Codes: B41J 2/04588 using a specific waveform
• CPC Class Codes: B41J 2/04591 Width of the driving signal being adjusted
• CPC Class Codes: B41J 2/04596 Non-ejecting pulses
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• 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 2/1626 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 2/1646 : thin film formation by sputtering
• CPC Class Codes: B41J 2/1648 : Production of print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2002/14419 : Manifold
• CPC Class Codes: B41J 2002/14491 : Electrical connection
• CPC Class Codes: Y10T 29/49345 : Catalytic device making

Abstract

A method of fabricating a plurality of nozzle arrangements for an inkjet printhead chip includes fabricating drive circuitry layers on a substrate with a CMOS fabrication process; depositing a first sacrificial layer on the substrate; depositing a heater layer for forming one or more heating circuits on the first sacrificial layer and etching the heater layer to form the heating circuits; depositing a resiliently flexible layer of dielectric material on the substrate to cover the heater layer and etching the dielectric layer to form one or more actuators and one or more ink ejection members; depositing a second sacrificial layer on the substrate to cover the actuators and the ink ejection members and etching the sacrificial layer to define deposition zones for one or more nozzle chamber walls and one or more roof walls; depositing a layer of a structural material on the second sacrificial layer to form the nozzle chamber walls and the roof walls; and etching away the sacrificial layers.

Claims

1. A method of fabricating a plurality of nozzle arrangements for an inkjet printhead chip, the method comprising the steps of:

fabricating drive circuitry layers on a substrate with a CMOS fabrication process;

depositing a first sacrificial layer on the substrate;

depositing a heater layer for forming one or more heating circuits on the first sacrificial layer and etching the heater layer to form the heating circuits;

depositing a resiliently flexible layer of dielectric material on the substrate to cover the heater layer and etching the dielectric layer to form one or more actuators and one or more ink ejection members;

depositing a second sacrificial layer on the substrate to cover the actuators and the ink ejection members and etching the sacrificial layer to define deposition zones for one or more nozzle chamber walls and one or more roof walls;

depositing a layer of a structural material on the second sacrificial layer to form the nozzle chamber walls and the roof walls; and

etching away the sacrificial layers.

2. A method as claimed in claim 1, which includes the step of depositing a bend compensation layer on the dielectric layer such that the deposition characteristics of the bend compensation layer are substantially the same as those of the heater layer, the bend compensation layer being of the same material as the heater layer.

3. A method as claimed in claim 1, in which the step of etching the second sacrificial layer includes the step of etching a deposition zone for a nozzle that projects from each roof wall and defines one or more ink ejection ports, the step of depositing the structural material layer being carried out to define sidewalls of the nozzles and to close the nozzles.

4. A method as claimed in claim 3, in which includes the step of planarizing the structural material layer to open the nozzles, thereby defining the ink ejection ports.

5. A method as claimed in claim 1, in which the step of etching the second sacrificial layer and depositing the structural layer is carried out such that the nozzle chamber walls and the roof walls define nozzle chambers in which respective actuators are positioned.

6. A method as claimed in claim 5, which includes the steps of depositing an ink passivation layer on the drive circuitry layers and etching the passivation layer to define vias for the heating circuits.