ELECTROMECHANICAL EFFECT IN METAL OXIDES

• US 20170069825A1
• Filed: 09/15/2016
• Published: 03/09/2017
• Est. Priority Date: 10/05/2010
• Status: Abandoned Application

• Current Assignee: Yeda Research and Development Co. Ltd. (Weizmann Institute of Science)
• Original Assignee: Yeda Research and Development Co. Ltd. (Weizmann Institute of Science)
• Inventors: LUBOMIRSKY, Igor, Korobko, Roman, Kossoy, Anna, Tuller, Harry L.
• Application Number:
  US15/265,870
• Publication Number:
  US 20170069825A1
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 30/074 by depositing piezoelectric or electrostrictive layers, e.g. aerosol or screen printing
• CPC Class Codes: H10N 30/076 by vapour phase deposition
• CPC Class Codes: H10N 30/2042 Cantilevers, i.e. having one fixed end
• CPC Class Codes: H10N 30/85 Piezoelectric or electrostrictive active materials
• CPC Class Codes: H10N 30/853 Ceramic compositions
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

This invention provides an electromechanical device comprising an active material comprising a metal oxide such as Ce_0.8Gd_0.2O_1.9 wherein the elastic modulus of metal oxide can be modulated by applying external electric field. The Ce_0.8Gd_0.2O_1.9 layer in a substrate\electrode\Ce_0.8Gd_0.2O_1.9\electrode structure or conductive substrate\Ce_0.8Gd_0.2O_1.9\electrode structure develops a stress upon applying an electric field. This invention provides methods for tailoring the elastic modulus of materials using an electric field for the generation of an electromechanical response.

Claims

1. A process for making an electromechanical device, said process comprising:

forming a first conductive layer,

forming a layer of a ceria-based material in contact with said first conductive layer; and

forming a second conductive layer in contact with said ceria-based material layer;

wherein upon application of an electric field said ceria-based material generates displacement, stress or a combination thereof.

2. The process of claim 1, wherein said first conductive layer is formed on a substrate by electron beam deposition.

3. The process of claim 1, wherein said layer of said ceria-based material is formed by radio frequency magnetron sputtering.

4. The process of claim 1 wherein said first and said second conductive layers are connected to a power supply.

5. The process of claim 1, wherein said ceria-based material is doped by a metal ion.

6. The process of claim 5, wherein said metal ion is a lanthanide.

7. The process of claim 6, wherein said metal ion is Gd.

8. The process of claim 1, wherein said ceria-based material is Ce_xGd_yO_z wherein x ranges between 0.95-0.63, said y ranges between 0.05-0.37 and said z ranges between 2−

(y/2).

9. The process of claim 2, wherein said Ce_xGd_yO_z is Ce_0.8Gd_0.2O_1.9.

10. The process of claim 1, wherein said ceria-based material is strain-free.

11. The process of claim 1, wherein the in-plane strain of said ceria-based material ranges between 0.1%-0.4%.

12. The process of claim 1, wherein said ceria-based material is poled.

13. The process of claim 1, wherein said displacement is at least 100 pm/V.

14. The process of claim 1, wherein said stress developed in said ceria-based material is at least 100 MPa.

15. The process of claim 1, wherein said device further comprises conductive contacts.

16. The process of claim 15, wherein said conductive contacts comprising Cr, Al, Ag, Ti, or combination thereof.