Transversely-excited film bulk acoustic resonator
US11139794B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 2020 |
| Grant date | Oct 5, 2021 |
| Priority date | — |
| Expiry date | Jul 2, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2003/0442
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Acoustic resonator devices and filters are disclosed. An acoustic resonator includes a substrate having a surface and a single-crystal 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 direction of acoustic energy flow of the primary acoustic mode is substantially orthogonal to the front and back surfaces of the diaphragm. The diaphragm is contiguous with the piezoelectric plate around at least 50% of a periphery of the diaphragm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.