Method for manufacturing rectangular parallelepiped-shaped single crystal, rectangular parallelepiped-shaped single crystal, method for manufacturing ceramics, ceramics, piezoelectric element, piezoelectric device, and electronic device

• US 10,461,241 B2
• Filed: 03/15/2016
• Issued: 10/29/2019
• Est. Priority Date: 03/17/2015
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Watanabe, Takayuki, Murakami, Shunsuke, Kubota, Makoto
• Primary Examiner(s): Rosenau, Derek J
• Application Number:
  US15/070,936
• Publication Number:
  US 20160273125A1
• Time in Patent Office: 1,323 Days
• Field of Search: 310358, 252 629 R, 252 629 PZ
• CPC Class Codes: C30B 29/30 Niobates; Vanadates; Tantalates
• CPC Class Codes: C30B 7/08 by cooling of the solution
• CPC Class Codes: H10N 30/097 by sintering
• CPC Class Codes: H10N 30/8542 Alkali metal based oxides, e.g. lithium, sodium or potassium niobates

Abstract

This invention is a method for manufacturing a rectangular parallelepiped-shaped single crystal containing sodium niobate of a perovskite structure as the main component, and the method includes a process of heating a mixture 1 of bismuth sodium niobate which is formed from particles containing a plurality of crystals represented by General Formula (1): Bi_2.5Na_m−1.5NbmO_3m+3 (m is an integer of 2 or more) and in which an average value m_a of the m values is larger than 6 and sodium containing alkali metal halide at 1200° C. or more and 1250° C. or less to obtain a rectangular parallelepiped-shaped single crystal containing sodium niobate as the main component.

Claims

1. A rectangular parallelepiped-shaped single crystal containing sodium niobate of a perovskite structure as a main component, wherein

the rectangular parallelpiped-shaped single crystal contains bismuth in an amount of 0.05 mol or more and 0.15 mol or less per mole of the sodium niobate,

a Na/Nb ratio of the rectangular parallelepiped-shaped single crystal is 0.82 or more and 1.00 or less, and

a ratio of a longest side length (L_max) to a shortest side length (L_min) of the rectangular parallelepiped is in a range of L_max/L_min of 4.0≤

L_max/L_min≤

8.5.

2. The rectangular parallelepiped-shaped single crystal containing sodium niobate as a main component according to claim 1, wherein the L_max is 9.4 μ

m or more and 20 μ

m or less.

3. Ceramics, which is obtained by sintering a green body containing the rectangular parallelepiped-shaped single crystal containing sodium niobate as a main component according to claim 1.

4. The ceramics according to claim 3, wherein the ceramics is oriented in a (110) plane or a (001) plane.

5. A piezoelectric element, comprising:

a first electrode;

a piezoelectric material portion; and

a second electrode, wherein a piezoelectric material configuring the piezoelectric material portion is the ceramics according to claim 4.

6. A piezoelectric device, comprising:

the piezoelectric element according to claim 5; and

at least one of a voltage application unit to the piezoelectric element and a power extracting unit from the piezoelectric element.

7. An electronic device;

comprising the piezoelectric element according to claim 5.

8. A rectangular parallelepiped-shaped single crystal powder, comprising:

a plurality of rectangular parallelepiped-shaped single crystals according to claim 1.