Transversely-excited film bulk acoustic resonator matrix filters with split die sub-filters
US11728784B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 29, 2021 |
| Grant date | Aug 15, 2023 |
| Priority date | — |
| Expiry date | Jun 29, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2003/023
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A radio frequency filter includes at least a first sub-filter and a second sub-filter connected in parallel between a first port and a second port. Each of the sub-filters has a piezoelectric plate having front and back surfaces, the back surface attached to a substrate, and portions of the piezoelectric plate forming diaphragms spanning respective cavities in the substrate. A conductor pattern is formed on the front surface of the plate, the conductor pattern includes interdigital transducers (IDTs) of a respective plurality of resonators, with interleaved fingers of each IDT disposed on a respective diaphragm of the plurality of diaphragms. A thickness of the portions of the piezoelectric plate of the first sub-filter is different from a thickness of the portions of the piezoelectric plate of the second sub-filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.