Method of fabricating a micro-electromechanical fluid ejection device

• US 6,986,202 B2
• Filed: 10/21/2004
• Issued: 01/17/2006
• 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): Tugbang, A. Dexter
• Application Number:
  US10/968,921
• Publication Number:
  US 20050055829A1
• Time in Patent Office: 453 Days
• Field of Search: 298/901, 296/11, 298/46, 298/30, 298/31, 216/2, 216/27, 216/79, 216/100, 347/54, 347/47, 347/48, 347/40, 347/44, 347/56, 347/61, 347/63, 347/65
• US Class Current: 29/890.1
• CPC Class Codes: B41J 11/0005 Curl smoothing, i.e. smoothing down corrugated printing material, e.g. by pressing means acting on wrinkled printing material
• CPC Class Codes: B41J 11/70 cutting perpendicular to the direction of paper feed
• CPC Class Codes: B41J 15/04 Supporting, feeding, or guiding devices; Mountings for web rolls or spindles
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• CPC Class Codes: B41J 2/14314 Structure of ink jet print heads with electrostatically actuated membrane
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/16 Production of nozzles
• 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 2002/14346 : Ejection by pressure produced by thermal deformation of ink chamber, e.g. buckling
• CPC Class Codes: B41J 2002/14435 : Moving nozzle made of thermal bend detached actuator
• CPC Class Codes: B41J 2002/14443 : Nozzle guard
• CPC Class Codes: B41J 2202/21 : Line printing
• CPC Class Codes: B41J 3/445 : Printers integrated in other types of apparatus, e.g. printers integrated in cameras
• 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: G07F 7/08 : by coded identity card or credit card or other personal identification means without personal verification means G07F7/02
• CPC Class Codes: G07F 7/086 : by passive credit-cards adapted therefor, e.g. constructive particularities to avoid counterfeiting, e.g. by inclusion of a physical or chemical security-layer for security documents G07D7/00; for the reading of record-carriers in general G06K7/00; for the design of coded credit-cards G06K19/10
• CPC Class Codes: G07F 7/12 : Card verification
• 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
• CPC Class Codes: H05K 1/0212 : Printed circuits or mounted components having integral heating means
• CPC Class Codes: H05K 1/0272 : Adaptations for fluid transport, e.g. channels, holes
• CPC Class Codes: H05K 2201/09063 : Holes or slots in insulating substrate not used for electrical connections
• CPC Class Codes: H05K 2201/09081 : Tongue or tail integrated in planar structure, e.g. obtained by cutting from the planar structure
• CPC Class Codes: H05K 2201/2072 : Anchoring, i.e. one structure gripping into another providing micro- or nanometer scale roughness on a metal surface H05K2203/0307
• CPC Class Codes: H05K 2203/308 : Sacrificial means, e.g. for temporarily filling a space for making a via or a cavity or for making rigid-flexible PCBs
• CPC Class Codes: Y10T 29/49083 : Heater type
• CPC Class Codes: Y10T 29/49117 : Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49126 : Assembling bases
• CPC Class Codes: Y10T 29/49128 : Assembling formed circuit to base
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49169 : Assembling electrical component directly to terminal or elongated conductor
• CPC Class Codes: Y10T 29/49172 : by molding of insulating material
• CPC Class Codes: Y10T 29/49401 : Fluid pattern dispersing device making, e.g., ink jet

Abstract

A method of fabricating a micro-electromechanical fluid ejection device includes the step of forming a first layer of a sacrificial material on a substrate incorporating a drive circuitry layer. A first electrically conducting layer, a first structural layer and a second electrically conducting layer are formed on the sacrificial material with the first structural layer interposed between the electrically conducting layers. The sacrificial material is formed so that the first electrically conducting layer defines a heating circuit connected to the drive circuitry, and the electrically conducting layers and the first structural layer define a fluid ejecting member connected to an actuator arm that is displaceable on heating and subsequent expansion of the first electrically conducting layer. A second layer of sacrificial material is formed on the second conducting layer layer. A second structural layer is formed on the second layer of sacrificial material. The sacrificial material is formed so that the second structural layer defines a nozzle chamber structure with the fluid ejecting member positioned in the nozzle chamber structure. The sacrificial material is removed so that the nozzle chamber structure defines a nozzle chamber and a fluid ejection port in fluid communication with the nozzle chamber.

Claims

1. A method of fabricating a micro-electromechanical fluid ejection device that comprises the steps of:

forming a first layer of a sacrificial material on a substrate incorporating a drive circuitry layer;

forming a first electrically conducting layer, a first structural layer and a second electrically conducting layer on the sacrificial material, with the first structural layer interposed between the electrically conducting layers, the sacrificial material being formed so that the first electrically conducting layer defines a heating circuit connected to the drive circuitry, and the electrically conducting layers and the first structural layer define a fluid ejecting member connected to an actuator arm that is displaceable on heating and subsequent expansion of the first electrically conducting layer;

forming a second layer of sacrificial material on the second electrically conducting layer;

forming a second structural layer on the second layer of sacrificial material, the sacrificial material being formed so that the second structural layer defines a nozzle chamber structure, with the fluid ejecting member positioned in the nozzle chamber structure; and

removing the sacrificial material so that the nozzle chamber structure defines a nozzle chamber and a fluid ejection port in fluid communication with the nozzle chamber.

2. A method as claimed in claim 1, which includes a step of etching the substrate to form a fluid inlet channel in fluid communication with the nozzle chamber.

3. A method as claimed in claim in claim 1, in which the step of forming the first electrically conducting layer, the first structural layer and the second electrically conducting layer includes steps of depositing the first electrically conducting layer, the first structural layer and the second electrically conducting layer and etching the electrically conducting layers and the first structural layer in a single operation.

4. A method as claimed in claim 1, in which the first sacrificial layer is deposited so that, when the first electrically conducting layer is formed, a break is formed between the actuator arm and the fluid ejecting member so that the fluid ejecting member is electrically isolated.

5. A method as claimed in claim 1, in which the step of forming the second structural layer includes the step of forming a nozzle rim positioned about the fluid ejection port.

6. A method as claimed in claim 1, in which the second layer of sacrificial material is formed so that the second structural layer defines a post for anchoring the actuator to the substrate.