Sandwich piezoelectric device with solid copper electrode
AssigneeMichelin Recherche et Technique S.A.
InventorDavid Alan Weston
Life of this patent
Estimating the term…
Abstract
Disclosed are apparatus and methodology for minimizing and compensating for cracking in piezoelectric devices so as to maintain long term functionality of the devices. Compensation for cracking is achieved by applying solid conductive electrodes over the entire surface of the piezoelectric device and extending the electrodes beyond the perimeter of the piezoelectric device. In this way electrical connections are maintained even in the presence of cracking. Cracking of the piezoelectric device is limited by minimizing the local bending moment of the piezoelectric device by way of applying insulative support materials that may vary in thickness.
Claims17
A piezoelectric device, comprising:
- a layer of piezoelectric material having a first surface, a second surface, and a perimeter;
- a first layer of conductive material completely covering said first surface and extending beyond the perimeter of said piezoelectric material;
- a second layer of conductive material completely covering said second surface and extending beyond the perimeter of said piezoelectric material;
- and
- a first insulating layer supporting said piezoelectric material and said first and second layers of conductive material.
A method for preserving piezoelectric device functionality in the presence of stress induced cracks, comprising:
- providing a layer of piezoelectric material having a first surface, a second surface, and a perimeter;
- completely covering said first surface with a first layer of conductive material;
- extending the first layer of conductive material beyond the perimeter of said piezoelectric material;
- completely covering said second surface with a second layer of conductive material;
- and
- extending the second layer of conductive material beyond the perimeter of said piezoelectric material.
Dependencies are inferred from the claim text.