Piezoelectric/electrostrictive device and method of manufacturing same

• US 6,472,799 B2
• Filed: 02/07/2002
• Issued: 10/29/2002
• Est. Priority Date: 10/01/1999
• Status: Expired due to Fees

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Takeuchi, Yukihisa, Kimura, Koji, Nanataki, Tsutomu
• Primary Examiner(s): Sircus, Brian
• Assistant Examiner(s): Zarroli, Michael C.
• Application Number:
  US10/072,189
• Publication Number:
  US 20020101136A1
• Time in Patent Office: 264 Days
• Field of Search: 310/321, 310/328, 310/330, 310/348, 29/253.5
• US Class Current: 310/348
• CPC Class Codes: H10N 30/01 Manufacture or treatment
• CPC Class Codes: H10N 30/05 Manufacture of multilayered piezoelectric or electrostrictive devices, or parts thereof, e.g. by stacking piezoelectric bodies and electrodes
• CPC Class Codes: H10N 30/053 by integrally sintering piezoelectric or electrostrictive bodies and electrodes
• CPC Class Codes: H10N 30/074 by depositing piezoelectric or electrostrictive layers, e.g. aerosol or screen printing
• CPC Class Codes: H10N 30/2043 connected at their free ends, e.g. parallelogram type
• CPC Class Codes: H10N 30/501 with non-rectangular cross-section in stacking direction, e.g. polygonal, trapezoidal

Abstract

A piezoelectric/electrostrictive device including a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting the thin plate sections and the movable section. At least one piezoelectric/electrostrictive element is arranged on the pair of thin plate section, and a hole is formed by both inner walls of the pair of thin plate sections, an inner wall of the movable section, and an inner wall of the fixation section. The pair of thin plate sections are previously bent in directions to make mutual separation so that they have an outwardly convex configuration.

Claims

1. A method for producing a piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

one or more piezoelectric/electrostrictive elements arranged on at least one thin plate section of said pair of thin plate sections; and

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section, said method comprising the step of;

cutting off a predetermined portion after forming said piezoelectric/electrostrictive element on at least said thin plate section to produce said piezoelectric/electrostrictive device in which at least a part of at least one thin plate section of said pair of thin plate sections is bent in a direction to make mutual separation.

2. A method for producing a piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

one or more piezoelectric/electrostrictive elements arranged on at least one thin plate section of said pair of thin plate sections; and

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section, said method comprising the step of;

cutting off a predetermined portion after forming said piezoelectric/electrostrictive element on at least said thin plate section to produce said piezoelectric/electrostrictive device in which at least parts of said pair of thin plate sections are bent in directions to make mutual separation.

3. A method for producing a piezoelectric/ electrostrictive device comprising:

a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

one or more piezoelectric/electrostrictive elements arranged on at least one thin plate section of said pair of thin plate sections; and

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section;

said method comprising the steps of;

integrally sintering a ceramic green laminate including at least a first ceramic green sheet having a window for forming at least said hole thereafter and second ceramic green sheets to be formed into said thin plate sections hereafter to produce a ceramic laminate including portions to be formed into said thin plate sections thereafter protruding outwardly;

forming said piezoelectric/electrostrictive element on at least an outer surface of a portion of said ceramic laminate to be formed into said thin plate section; and

producing a ceramic substrate formed with at least said piezoelectric/electrostrictive element in which said pair of thin plate sections are bent in directions to make mutual separation, by means of at least one time of cutoff treatment for said ceramic laminate formed with said piezoelectric/electrostrictive element.

4. The method for producing said piezoelectric/electrostrictive device according to claim 3, wherein those having a difference in sintering shrinkage speed and/or sintering shrinkage amount are used for said first and second ceramic green sheets respectively.

5. The method for producing said piezoelectric/electrostrictive device according to claim 3, wherein:

said step of forming said piezoelectric/electrostrictive element is performed in accordance with a film formation method; and

at least any one of a pair of electrodes and/or a piezoelectric/electrostrictive layer is integrated by sintering with at least said outer surface of said portion to be formed into said thin plate section.

6. The method for producing said piezoelectric/electrostrictive device according to claim 3, further comprising exposing said hole by means of a cutoff treatment for said ceramic laminate.

8. The method for producing said piezoelectric/electrostrictive device according to claim 6, wherein said precursor is formed while controlling a difference in thermal expansion at least between a material for said portion to be formed into said thin plate section and a material for said piezoelectric/electrostrictive element when said precursor for constructing at least said part of said piezoelectric/electrostrictive element is formed on said ceramic green laminate.

7. A method for producing a piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

one or more piezoelectric/electrostrictive elements arranged on at least one thin plate section of said pair of thin plate sections; and

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section;

said method comprising the steps of;

producing a ceramic green laminate including at least a ceramic green sheet having a window for forming at least said hole thereafter and ceramic green sheets to be formed into said thin plate sections thereafter;

forming a precursor for constructing at least a part of said piezoelectric/electrostrictive element on at least an outer surface of a portion to be formed into said thin plate section, of said ceramic green laminate;

co-firing said ceramic green laminate and said precursor for constructing at least said part or all of said piezoelectric/electrostrictive element so that a ceramic laminate including portions to be formed into said thin plate sections thereafter protruding outwardly is produced, and at least said part or all of said piezoelectric/electrostrictive element is formed on at least said outer surface of said portion to be formed into said thin plate section; and

producing a ceramic substrate in which said pair of thin plate sections are bent in directions to make mutual separation, by means of at least one time of cutoff treatment for said ceramic laminate.