Method of fabricating a micro-electro-mechanical fluid ejector

• US 20010023523A1
• Filed: 05/23/2001
• Published: 09/27/2001
• Est. Priority Date: 10/15/1998
• Status: Active Grant

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Chen, Jingkuang, Pan, Feixia, Kubby, Joel A.
• Granted Patent: US 6,662,448 B2
• Time in Patent Office: Days
• US Class Current: 29/25.35
• CPC Class Codes: B41J 2/14314 Structure of ink jet print heads with electrostatically actuated membrane
• CPC Class Codes: B41J 2/16 Production of nozzles
• 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 2/1639 sacrificial molding
• CPC Class Codes: B41J 2/1642 thin film formation by CVD [chemical vapor deposition]
• CPC Class Codes: B41J 2002/041 Electromagnetic transducer
• CPC Class Codes: H04R 17/00 Piezoelectric transducers; Electrostrictive transducers piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners H10N30/00
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49128 Assembling formed circuit to base
• CPC Class Codes: Y10T 29/49156 with selective destruction of conductive paths
• CPC Class Codes: Y10T 29/49401 Fluid pattern dispersing device making, e.g., ink jet

Abstract

A micro-electromechanical fluid ejector that is easily fabricated in a standard polysilicon surface micromachining process is disclosed, which can be batch fabricated at low cost using existing external foundry capabilities. In addition, the surface micromachining process has proven to be compatible with integrated microelectronics, allowing for the monolithic integration of the actuator with addressing electronics. A voltage drive mode and a charge drive mode for the power source actuating a deformable membrane is also disclosed.

Claims

1. A method of fabricating a micro-electromechanical fluid ejector, comprising:

providing a semiconductor substrate having a top surface;

depositing an insulating layer on the top surface of the semiconductor substrate;

forming a conductor on top of the insulating layer;

forming a conductive membrane over the conductor, thereby providing an enclosed actuator chamber;

forming a nozzle plate over the conductive member, thereby providing a partially enclosed pressure chamber.

2. The method of fabricating a micro-electromechanical fluid ejector as claimed in

claim 1

, wherein forming the conductor comprises:

depositing a conductor layer on top of the insulating layer;

depositing a photoresist layer on top of the conductor layer;

patterning the photoresist layer; and

transferring the pattern on the photoresist layer into the conductor layer; and

removing portions of the conductor layer based on the pattern to form the conductor.

3. The method of fabricating a micro-electromechanical fluid ejector as claimed in

claim 1

, wherein forming the conductive membrane further comprises:

depositing a sacrificial layer on top of the conductor and insulating layer;

forming a hole on the top surface of the sacrificial layer;

removing portions of the sacrificial layer to provide the approximate length of the conductive membrane;

depositing a conductive membrane layer on top of the sacrificial layer;

forming the conductive membrane from the conductive membrane layer the conductive membrane having a nipple formed by the hole; and

removing the sacrificial layer.

4. The method of fabricating a micro-electromechanical fluid ejector as claimed in

claim 1

, further comprising:

attaching a power source to the conductor and the conductive membrane, such that when the power source is activated, the conductive membrane deflects towards the conductor.

5. A method of fabricating a micro-electromechanical device, the device comprising first and second layers which can move towards each other, the first layer having a nonconducting region, the method including a step of forming a nipple on the inner surface of the second layer, the nipple aligned with the nonconductive region, to prevent contact between the two layers.