Thin film piezoelectric element and manufacturing method thereof, micro-actuator, head gimbal assembly and disk drive unit with the same
US9450171B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2013 |
| Grant date | Sep 20, 2016 |
| Priority date | — |
| Expiry date | Mar 29, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N30/704
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A thin film piezoelectric element of the present invention includes a substrate and a piezoelectric thin film stack formed on the substrate. The piezoelectric thin film stack includes a top electrode layer, a bottom electrode layer and a piezoelectric layer sandwiched between the top electrode layer and the bottom electrode layer, wherein the piezoelectric layer includes a first piezoelectric layer and a second piezoelectric layer whose compositions have different phase structures. The present invention can obtain high piezoelectric constants, enhanced coercive field strength and good thermal stability, thereby enabling larger applied field strength without depolarization and achieving a large stroke for its applied device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.