Piezoelectric thin film resonator, filter, and multiplexer
US10615776B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 2018 |
| Grant date | Apr 7, 2020 |
| Priority date | — |
| Expiry date | Sep 29, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2003/021
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A piezoelectric thin film resonator includes: a substrate; a lower electrode located on the substrate through an air gap; a piezoelectric film located so as to have a resonance region where the lower electrode and an upper electrode face each other across the piezoelectric film and having a lower piezoelectric film and an upper piezoelectric film, in an extraction region where the lower electrode is extracted from the resonance region, a lower end of a first end face of the lower piezoelectric film being substantially aligned with or located further out than an outer periphery of the air gap, a second end face of the upper piezoelectric film being inclined, an upper end of the second end face being substantially aligned with or located further in than the outer periphery, the lower piezoelectric film having a substantially uniform film thickness between the first end face and the second end face.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.