Electromechanical transducer element, liquid discharge head, liquid discharge device, and liquid discharge apparatus

Patent metadata

Field	Value
Publication number	US-9969161-B2
Application number	US-201715447266-A
Country	US
Kind code	B2
Filing date	Mar 2, 2017
Priority date	Mar 4, 2016
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

An electromechanical transducer element includes a first electrode, a second electrode, and a piezoelectric material. The piezoelectric material is disposed between the first electrode and the second electrode and deformable with a voltage applied in accordance with a drive signal. The piezoelectric material is made of a composite oxide having a perovskite structure preferentially oriented in at least one of a (100) plane and a (001) plane. A drop in diffraction intensity is included in a rocking curve corresponding to at least one of a (200) plane and a (002) plane measured at a position of 2θ where the diffraction intensity is largest at a peak of diffraction intensity corresponding to the (200) plane out of peaks of diffraction intensity measured by an X-ray diffraction θ-2θ method.

First claim

What is claimed is:

1. An electromechanical transducer element, comprising:
a first electrode;
a second electrode; and
a piezoelectric material that is disposed between the first electrode and the second electrode and is deformable with a voltage applied in accordance with a drive signal,
wherein the piezoelectric material is made of a composite oxide having a perovskite structure preferentially oriented in at least one of a (100) plane and a (001) plane, and
wherein for the piezoelectric material, a drop in diffraction intensity is included in a rocking curve corresponding to at least one of a (200) plane and a (002) plane measured at a position of 2θ where the diffraction intensity is largest at a peak of diffraction intensity corresponding to the (200) plane out of peaks of diffraction intensity measured by an X-ray diffraction θ-2θ method, and
wherein the first electrode is formed of a material including platinum, and a root-mean-square height Sq of surface roughness of a plane of the first electrode on which the piezoelectric material is formed is three or less.

2. The electromechanical transducer element according to claim 1 , wherein the piezoelectric material has only two peaks in the rocking curve with the drop interposed between the two peaks.

3. The electromechanical transducer element according to claim 1 ,
wherein a full width at half maximum of the rocking curve falls within a range of from 10 to 12.4 degrees.

4. The electromechanical transducer element according to claim 1 ,
further comprising a seed layer made of titanium oxide or lead titanate between the piezoelectric material and the first electrode.

5. A liquid discharge head, comprising:
a discharge orifice to discharge liquid;
a liquid chamber communicated with the discharge orifice;
a displacement plate constituting at least one wall of the liquid chamber; and
the electromechanical transducer element according to claim 1 to displace the displacement plate in accordance with the drive signal.

6. A liquid discharge device comprising:
the liquid discharge head according to claim 5 to discharge liquid from the discharge orifice in accordance with the drive signal; and
at least one external component integrated with the liquid discharge head as a single unit.

7. A liquid discharge apparatus comprising the liquid discharge head according to claim 5 to discharge the liquid from the discharge orifice in accordance with the drive signal.

8. A method of producing the electromechanical transducer element according to claim 1 , the method comprising directly or indirectly forming the piezoelectric material on the first electrode of the electromechanical transducer element.

9. The method according to claim 8 , wherein the forming includes forming the first electrode directly or indirectly on a substrate under a condition in which a temperature of the substrate is 400° C. or higher.

10. The electromechanical transducer element according to claim 1 ,
wherein the piezoelectric material includes two columnar crystals having different growth directions, and
wherein side surfaces of the respective columnar crystals partially interfere with each other.

Assignees

• Shinkai Masaru
• Mizukami Satoshi
• Masuda Toshiaki
• Ricoh Co Ltd

Inventors

• Shinkai Masaru
• Mizukami Satoshi
• Masuda Toshiaki

Classifications

• B41J2/164

  thin film formation · CPC title

• B41J2/14233 Primary

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

• H01L41/1875

  Electricity · mapped topic

• B41J2/14201

  Structure of print heads with piezoelectric elements · CPC title

• C04B2235/3232

  Titanium oxides or titanates, e.g. rutile or anatase · CPC title