Fluid ejection device that incorporates covering formations for actuators of the fluid ejection device

• US 6,840,600 B2
• Filed: 11/17/2003
• Issued: 01/11/2005
• 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): Gordon, Raquel Yvette
• Application Number:
  US10/713,095
• Publication Number:
  US 20040104972A1
• Time in Patent Office: 421 Days
• Field of Search: 347/54, 347/68, 347/69, 347/70, 347/71, 347/72, 347/50, 347/40, 347/20, 347/44, 347/47, 347/27, 347/63, 399/261, 361/700, 310328-330, 298/901
• US Class Current: 347/54
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/1601 Production of bubble jet print heads B41J2/1606, B41J2/162 take precedence
• 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 2/1637 molding
• 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 2/17513 Inner structure
• CPC Class Codes: B41J 2/17596 Ink pumps, ink valves
• CPC Class Codes: B41J 2002/041 Electromagnetic transducer
• CPC Class Codes: B41J 2202/21 : Line printing
• CPC Class Codes: G06F 21/79 : in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06F 21/86 : Secure or tamper-resistant housings
• CPC Class Codes: G06F 2221/2129 : Authenticate client device independently of the user
• 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 micro-electromechanical fluid ejection device includes a substrate that incorporates drive circuitry. Nozzle chamber walls and a roof are positioned on the substrate to define a nozzle chamber with the roof defining a fluid ejection port in fluid communication with the nozzle chamber. A fluid-ejecting member is operatively positioned with respect to the nozzle chamber. The fluid-ejecting member is displaceable with respect to the substrate to eject fluid from the fluid ejection port. An actuator is connected to the fluid-ejecting member and to the drive circuitry. The actuator is displaceable upon receipt of an electrical signal from the drive circuitry to displace the fluid-ejecting member and thus eject fluid from the fluid ejection port. A covering formation is positioned on the substrate so that the substrate and the covering formation define an air chamber, the actuator being positioned within the air chamber.

Claims

1. A micro-electromechanical fluid ejection device that comprises

a substrate that incorporates drive circuitry;

nozzle chamber walls and a roof that are positioned on the substrate to define a nozzle chamber with the roof defining a fluid ejection port in fluid communication with the nozzle chamber;

a fluid-ejecting member that is operatively positioned with respect to the nozzle chamber, the fluid-ejecting member being displaceable with respect to the substrate to eject fluid from the fluid ejection port;

an actuator that is connected to the fluid-ejecting member and to the drive circuitry, the actuator being displaceable upon receipt of an electrical signal from the drive circuitry to displace the fluid-ejecting member and thus eject fluid from the fluid ejection port; and

a covering formation that is positioned on the substrate so that the substrate and the covering formation define an air chamber, the actuator being positioned within the air chamber.

2. A device as claimed in claim 1, which is the product of an integrated circuit fabrication technique.

3. A device as claimed in claim 2, in which the substrate includes a silicon wafer substrate, a CMOS drive circuitry layer positioned on the silicon wafer substrate and an ink passivation layer positioned on the CMOS drive circuitry layer.

4. A device as claimed in claim 3, in which each fluid-ejecting member is positioned in its respective nozzle chamber and is displaceable towards and away from the fluid ejection port.

5. A device as claimed in claim 3, in which each nozzle arrangement includes a work-transmitting structure that is displaceable with respect to the substrate and is connected to the fluid-ejecting member so that displacement of the work-transmitting structure results in displacement of the fluid-ejecting member, the actuator being connected to the work-transmitting structure to displace the work-transmitting structure.

6. A device as claimed in claim 5, in which the roof, the work-transmitting structure and the covering formation together define a protective structure that is positioned in a common plane.

7. A device as claimed in claim 6, in which the roof, the work-transmitting structure and the covering formation are configured so that the protective structure is unitary.

8. A device as claimed in claim 3, in which a plurality of fluid inlet channels are defined through the substrate, with each fluid inlet channel opening into a respective nozzle chamber.