Piezoelectric ceramic thick film element, array of elements, and devices

• US 7,091,650 B2
• Filed: 12/20/2004
• Issued: 08/15/2006
• Est. Priority Date: 02/25/2003
• Status: Expired due to Fees

• Current Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Original Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Inventors: Weisberg, Michael C., Buhler, Steven A., Fitch, John S., Wong, William S., Solberg, Scott E., Xu, Baomin, Littau, Karl A., Elrod, Scott A.
• Primary Examiner(s): BUDD, MARK OSBORNE
• Application Number:
  US11/017,494
• Publication Number:
  US 20050104479A1
• Time in Patent Office: 603 Days
• Field of Search: 310/324, 310/328, 310330-332
• US Class Current: 310/330
• CPC Class Codes: B41J 2/161 of film type, deformed by bending and disposed on a diaphragm
• CPC Class Codes: B41J 2/1623 bonding and adhesion
• CPC Class Codes: B41J 2/1632 machining
• CPC Class Codes: B41J 2/1634 laser machining
• CPC Class Codes: B41J 2/1637 molding
• CPC Class Codes: B41J 2/1646 thin film formation by sputtering
• CPC Class Codes: H01L 2221/68368 used in a transfer process involving at least two transfer steps, i.e. including an intermediate handle substrate
• CPC Class Codes: H10N 30/073 by fusion of metals or by adhesives
• CPC Class Codes: H10N 30/074 by depositing piezoelectric or electrostrictive layers, e.g. aerosol or screen printing
• CPC Class Codes: H10N 30/081 by coating or depositing using masks, e.g. lift-off
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/435 Solid dielectric type
• CPC Class Codes: Y10T 29/49128 Assembling formed circuit to base
• CPC Class Codes: Y10T 29/4913 Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49133 with component orienting
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/4981 Utilizing transitory attached element or associated separate material

Abstract

A piezoelectric thick film element array includes at least one piezoelectric element structure having a thickness between 10 μm to 100 μm formed by a deposition process. The at least one piezoelectric element is patterned during the deposition process, and includes a first electrode deposited on a first surface of the piezoelectric elements structure, and a second electrode deposited on a second surface of the piezoelectric element structure. In a further embodiment, several devices are provided using a piezoelectric element or an array having a piezoelectric element structure with a thickness of between 10 μm to 100 μm formed by a deposition process. These devices include microfluidic ejectors, transducer arrays and catheters.

Claims

1. At least one piezoelectric element arrangement comprising:

at least one deposited, poled and tested piezoelectric element structure having a thickness of 10 μ

m to 100 μ

m formed by a deposition process directly on a first substrate, wherein the piezoelectric element structure and the first substrate are comprised of materials which permit removal of the piezoelectric element structure from the first substrate by a laser lift off process, the piezoelectric element structure being physically separate and apart from the first substrate on which the piezoelectric element structure was deposited and formed;

a first electrode deposited on a first surface of the piezoelectric element structure; and

a second electrode deposited on a second surface of the piezoelectric element structure,

wherein the at least one piezoelectric element structure is bonded directly to a target substrate by a bonding layer, the target substrate comprised of a material which will cause the target substrate to be destroyed and rendered inoperative at temperatures reached in a preparation process used to make the poled and tested piezoelectric element structure, and

wherein the bonding layer is formed by bonding materials which include at least one of nonconductive epoxy bonding material containing conductive particles, nonconductive epoxy bonding material alone, or thin film metal bonding material.

2. The at least one piezoelectric element arrangement according to claim 1, wherein the at least one piezoelectric element is an array of elements.

3. The at least one piezoelectric element arrangement of claim 2, wherein the thicknesses of each element in the array are substantially identical.

4. The at least one piezoelectric element arrangement according to claim 1, wherein the at least one piezoelectric element structure is patterned.

5. The at least one piezoelectric element arrangement according to claim 4, wherein the at least one patterned piezoelectric element structure is patterned by a deposition process.

6. The at least one piezoelectric element arrangement according to claim 5, wherein the pattern may be of any geometric shape.

17. The at least one piezoelectric element arrangement according to claim 1, wherein the deposited, poled and tested piezoelectric element structure is comprised of a screen printed polycrystalline.

18. The at least one piezoelectric element arrangement according to claim 1, wherein the material of the target substrate includes at least one of a plastic or a metal foil.

19. The device of claim 1, wherein the bonding materials are the non-conductive epoxy bonding materials containing conductive particles.

20. The device of claim 1, wherein the bonding materials are the non-conductive epoxy bonding materials alone.

21. The device of claim 1, wherein the bonding materials are the thin film metal bonding material.

7. A device comprising:

a piezoelectric element including,

at least one deposited, poled and tested piezoelectric element structure having a thickness of between 10 μ

m to 100 μ

m formed by a deposition process on a first substrate,

a first electrode deposited on a first surface of the at least one piezoelectric element structure,

a second electrode deposited on a second surface of the at least one piezoelectric element structure; and

a target system to which the deposited poled and tested piezoelectric element structure is bonded,

wherein the device is physically separate and apart from the first substrate on which the piezoelectric element structure was deposited and formed, and

wherein the bond between the at least one deposited, poled and tested piezoelectric element structure and the target system is by at least one of a nonconductive epoxy bonding material containing conductive particles, nonconductive epoxy bonding material alone, or a thin film metal bonding material, wherein electrical contact is maintained between the at least one poled and tested piezoelectric element structure and the target system.

8. The device according to claim 7, wherein the target system is a microfluid pump body, and wherein the at least one deposited, poled and tested piezoelectric element structure is an actuator of the microfluid pump body.

9. The device according to claim 8, wherein the microfluid pump body is at least one of a jet printhead body or an acoustic ejector body.

10. The device according to claim 9, further including a metal foil such as copper bonded to a second surface of the deposited, poled and tested piezoelectric element structure, the metal foil acting as a current return path for the device.

12. The device according to claim 9, wherein the at least one deposited, poled and tested piezoelectric element structure is bonded to a metal diaphragm which is bonded to an ink cavity body of the microfluid pump, wherein the at least one deposited, poled and tested piezoelectric element and the metal diaphragm form a bending type actuator for pushing ink out.

14. The device according to claim 7, wherein the target system is one of a micromachined transducer array or a micromachined annular array.

15. The device according to claim 7, wherein the target system is part of a catheter.

16. The device according to claim 7, wherein the target system is comprised of a material which will cause the target system to be destroyed and rendered inoperative at temperatures reached in a preparation process used to make the poled and tested piezoelectric element structure.

22. The device according to claim 7, wherein the bonding materials are the nonconductive epoxy bonding materials containing conductive particles.

23. The device according to claim 7, wherein the bonding materials are the nonconductive epoxy bonding materials alone.

24. The device according to claim 7, wherein the bonding materials are the thin film metal bonding material.

11. A device comprising:

a piezoelectric element including,

at least one deposited, poled and tested piezoelectric element structure having a thickness of between 10 μ

m to 100 μ

m formed by a deposition process on a first substrate,

a first electrode deposited on a first surface of the at least one piezoelectric element structure,

a second electrode deposited on a second surface of the at least one piezoelectric element structure; and

a target system to which the deposited poled and tested piezoelectric element structure is bonded, wherein the device is physically separate and apart from the first substrate on which the piezoelectric element structure was deposited and formed,

wherein the target system is a microfluid pump body, and the at least one deposited, poled and tested piezoelectric element structure is an actuator of the microfluid pump body, and

wherein the microfluid pump body is at least one of a plastic jet printhead body or a plastic acoustic ejector body.

13. A device comprising:

a piezoelectric element including,

at least one deposited, poled and tested piezoelectric element structure having a thickness of between 10 μ

m to 100 μ

m formed by a deposition process on a first substrate,

a first electrode deposited on a first surface of the at least one piezoelectric element structure,

a second electrode deposited on a second surface of the at least one piezoelectric element structure;

a target system to which the deposited poled and tested piezoelectric element structure is bonded, wherein the device is physically separate and apart from the first substrate on which the piezoelectric element structure was deposited and formed,

wherein the target system is a microfluid pump body which has a metal diaphragm which is bonded to the fluid cavity of the microfluid pump body, and

an insulating layer between the at least one deposited, poled and tested piezoelectric element structure and the metal diaphragm,

wherein the at least one deposited, poled and tested piezoelectric element structure is bonded to the metal diaphragm by a bonding layer and the insulating layer, and

wherein the deposited, poled and tested piezoelectric element structure and the metal diaphragm form a bending type actuator for pushing ink out.