Method of manufacture of a pulsed magnetic field ink jet printer

• US 6,225,138 B1
• Filed: 07/10/1998
• Issued: 05/01/2001
• 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): Mills, Gregory
• Assistant Examiner(s): Powell, Alva C
• Application Number:
  US09/113,114
• Time in Patent Office: 1,026 Days
• Field of Search: 216/22, 216/27, 438/21
• US Class Current: 438/21
• 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 2/1639 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: 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

This patent describes a method of manufacturing a pulsed magnetic field ink jet print head wherein an array of nozzles are formed on a substrate utilising planar monolithic deposition, lithographic and etching processes. Multiple ink jet heads are formed simultaneously on a single planar substrate such as a silicon wafer. The print heads can be formed utilising standard VLSI/ULSI processing and can include integrated drive electronics formed on the same substrate. The drive electronics preferably being of a CMOS type. In the final construction, ink can be ejected from the substrate substantially normal to the substrate plane.

Claims

1. A method of manufacturing an ink jet printhead which includes;

providing a substrate;

depositing a doped layer on the substrate and etching said layer to create an array of nozzles on the substrate with a nozzle chamber in communication with each nozzle; and

utilising planar monolithic deposition, lithographic and etching processes to create a locking mechanism and a magnetically responsive paddle which can be latched by the locking mechanism, a paddle and a locking mechanism being associated with each nozzle chamber, the paddle being influenced by a pulsed magnetic field which is common to all the nozzles of the array and which is arranged so as to cause the paddle to eject a drop of ink from the nozzle when the locking mechanism is in a first state of actuation, and the locking mechanism being arranged so as to prevent the paddle from ejecting a drop of ink from the nozzle when the latch is in a second state of actuation, the latch mechanisms of the nozzles being individually addressable.

2. A method of manufacturing an ink jet printhead as claimed in claim 1 wherein multiple ink jet printheads are formed simultaneously on the substrate.

3. A method of manufacturing an ink jet printhead as claimed in claim 1 wherein said substrate is a silicon wafer.

4. A method of manufacturing an ink jet printhead as claimed in claim 1 wherein integrated drive electronics are formed on the same substrate.

5. A method of manufacturing an ink jet printhead as claimed in claim 4 wherein said integrated drive electronics are formed using a CMOS fabrication process.

6. A method of manufacturing an ink jet printhead as claimed in claim 1 wherein ink is ejected from said substrate normal to said substrate.

7. A method of manufacturing an ink jet printhead including the steps of:

a) epitaxially depositing a boron doped silicon layer on a silicon wafer;

b) epitaxially depositing a lightly doped silicon layer on the boron doped silicon layer;

c) depositing and etching circuitry defining layers on the lightly doped silicon layer to form drive and data distribution circuitry;

d) crystallographically etching the lightly doped silicon layer and a part of the circuitry layer to form a nozzle chamber;

e) depositing a sacrificial layer on the circuitry defining layers, the sacrificial layer extending into the nozzle chamber;

f) applying paddle-defining layers to the sacrificial layer;

g) back-etching the wafer to the boron doped silicon layer;

h) back-etching the boron doped silicon layer to create a nozzle; and

i) removing the sacrificial layer so that a paddle defined by the paddle-defining layers is suspended above the nozzle chamber.

8. The method as claimed in claim 7 which includes back-etching the boron doped silicon layer to create a nozzle rim.

9. The method as claimed in claim 7 in which the steps of applying the paddle-defining layers include:

depositing a seed layer for electroplating;

depositing, exposing and developing resist;

electroplating ferromagnetic material;

stripping said resist; and

etching said seed layer.

10. The method as claimed in claim 9 which includes, prior to deposition of the seed layer, the following steps:

depositing a first layer of non-conductive material on the layer of sacrificial material;

depositing and etching a layer of conductive material on said first layer of non-conductive material; and

depositing a second layer of non-conductive material on the layer of conductive material to form a locking mechanism for the paddle.

11. The method as claimed in claim 9 which includes, after etching said seed layer, depositing and etching a layer of silicon nitride over the ferromagnetic material and that part of the sacrificial layer along one edge of the ferromagnetic material to form a spring for the paddle.