Thin film piezoelectric element, thin film piezoelectric actuator, thin film piezoelectric sensor, hard drive disk, and inkjet printer device
US9331262B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 2013 |
| Grant date | May 3, 2016 |
| Priority date | — |
| Expiry date | Oct 17, 2034 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2202/03
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A thin film piezoelectric element according to the present invention includes a potassium sodium niobate thin film having a structure in which a plurality of crystal grains are present in a film thickness direction; and a pair of electrode films sandwiching the potassium sodium niobate thin film. When the potassium sodium niobate thin film is divided into three regions of the same thickness in the film thickness direction and average crystal grain sizes A1, A2, and A3 of the respective regions are determined, a ratio m/M of the smallest average crystal grain size m among A1, A2, and A3 to the largest average crystal grain size M among A1, A2, and A3 is 10% to 80%. The region having the smallest average crystal grain size m lies next to one of the pair of electrode films.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.