Filter devices having high power transversely-excited film bulk acoustic resonators
US10985730B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 2020 |
| Grant date | Apr 20, 2021 |
| Priority date | — |
| Expiry date | Aug 18, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/13
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
There is disclosed acoustic resonators and filter devices. An acoustic resonator includes a substrate having a surface and a Z-cut piezoelectric plate having parallel front and back surfaces, the back surface attached to the surface of the substrate except for a portion of the piezoelectric plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface of the single-crystal piezoelectric plate such that interleaved fingers of the IDT are disposed on the diaphragm. The IDT is configured to excite a primary acoustic mode in the diaphragm in response to a radio frequency signal applied to the IDT. A thickness of the interleaved fingers of the IDT is greater than or equal to 0.85 times a thickness of the diaphragm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.