Piezoelectric layer, piezoelectric component, piezoelectric actuator, piezoelectric sensor, hard-disk drive and ink jet printer

Patent metadata

Field	Value
Publication number	US-10472250-B2
Application number	US-201514934988-A
Country	US
Kind code	B2
Filing date	Nov 6, 2015
Priority date	Nov 12, 2014
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

A piezoelectric layer made of potassium sodium niobate which is a perovskite type compound represented by the formula ABO 3 , wherein, in the Raman spectroscopy measurement of the piezoelectric layer which is performed while the piezoelectric layer is rotated in the in-plane direction, the measured intensity of the lattice vibration region of the perovskite type compound in the Raman spectrum obtained in polarized Raman spectroscopy measurement (yx) has a periodicity of approximately 90°, wherein, the polarized Raman spectroscopy measurement (yx) is performed while the piezoelectric layer is rotated in the in-plane direction and Raman scattering light is polarized in a direction perpendicular to that of the incident light.

First claim

What is claimed is:

1. A piezoelectric layer composed of potassium sodium niobate which is a perovskite type compound represented by the formula ABO 3 ,
wherein, in the Raman spectroscopy measurement of the piezoelectric layer which is performed while the piezoelectric layer is rotated in an in-plane direction, a measured intensity of a lattice vibration region of the perovskite type compound in a Raman spectrum obtained in polarized Raman spectroscopy measurement (yx) has a periodicity of approximately 90°,
the polarized Raman spectroscopy measurement (yx) is performed while the piezoelectric layer is rotated in the in-plane direction and Raman scattering light is polarized in a direction perpendicular to that of the incident light, and
a crystal lattice in the piezoelectric layer is matched in a plane direction.

2. The piezoelectric layer of claim 1 , wherein, in the Raman spectroscopy measurement of the piezoelectric layer, with respect to the measured intensities of the lattice vibration region of the perovskite type compound in the Raman spectra obtained by performing polarized Raman spectroscopy measurement (yy) and polarized Raman spectroscopy measurement (yx) while the piezoelectric layer is rotated in the in-plane direction, a periodicity of approximately 90° exists in both the polarized Raman spectroscopy measurement (yy) and the polarized Raman spectroscopy measurement (yx), and the period of the measured intensity in the polarized Raman spectroscopy measurement (yy) deviates from that in the polarized Raman spectroscopy measurement (yx) by approximately 45°, and
the polarized Raman spectroscopy measurement (yy) is performed when the Raman-scattering light is polarized in a direction parallel to that of the incident light, and the polarized Raman spectroscopy measurement (yx) is performed when the Raman-scattering light is polarized in a direction perpendicular to that of the incident light.

3. The piezoelectric layer of claim 1 , wherein, in the Raman spectrum obtained by performing the polarized Raman spectroscopy measurement (yx) of the piezoelectric layer, there are at least one peak in vicinity of 550 cm −1 and in vicinity of 610 cm −1 respectively, and the intensity ratio of the measured intensity of the peak in vicinity of 550 cm −1 to that in vicinity of 610 cm −1 shows a periodicity of approximately 90°, and the difference between the maximal value and the minimal value of the intensity ratio is 0.3 or more and 1.0 or less.

4. A piezoelectric component comprising an upper electrode and a lower electrode on the piezoelectric layer of claim 1 .

5. A piezoelectric actuator using the piezoelectric component of claim 4 .

6. A piezoelectric sensor using the piezoelectric component of claim 4 .

7. A hard-disk drive comprising the piezoelectric actuator of claim 5 .

8. An ink jet printer comprising the piezoelectric actuator of claim 5 .

9. A piezoelectric component comprising an upper electrode and a lower electrode on the piezoelectric layer of claim 2 .

10. A piezoelectric component comprising an upper electrode and a lower electrode on the piezoelectric layer of claim 3 .

11. A piezoelectric actuator using the piezoelectric component of claim 9 .

12. A piezoelectric actuator using the piezoelectric component of claim 10 .

13. A piezoelectric sensor using the piezoelectric component of claim 9 .

14. A piezoelectric sensor using the piezoelectric component of claim 10 .

15. A hard-disk drive comprising the piezoelectric actuator of claim 11 .

16. A hard-disk drive comprising the piezoelectric actuator of claim 12 .

17. An ink jet printer comprising the piezoelectric actuator of claim 11 .

18. An ink jet printer comprising the piezoelectric actuator of claim 12 .

Assignees

• Tdk Corp

Inventors

• Oishi Masahiro
• Matsutani Atsuo
• Ohta Ryu

Classifications

• B41J2202/03

  Specific materials used · CPC title

• G01N21/65

  Raman scattering · CPC title

• B41J2/14233 Primary

  of film type, deformed by bending and disposed on a diaphragm · CPC title

• C01P2002/34

  perovskite-type (ABO3) · CPC title

• C01P2006/40

  Electric properties · CPC title