Multi-port filter using transversely-excited film bulk acoustic resonators
US11888463B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 10, 2020 |
| Grant date | Jan 30, 2024 |
| Priority date | — |
| Expiry date | Aug 8, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2003/0435
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Filter devices and methods are disclosed. A single-crystal piezoelectric plate is attached to substrate, portions of the piezoelectric plate forming a plurality of diaphragms spanning respective cavities in the substrate. A conductor pattern formed on the piezoelectric plate defines a low band filter including low band shunt resonators and low band series resonators and a high band filter including high band shunt resonators and high band series resonators. Interleaved fingers of interdigital transducers (IDTs) of the low band shunt resonators are disposed on respective diaphragms having a first thickness, interleaved fingers of IDTs of the high band series resonators are disposed on respective diaphragms having a second thickness less than the first thickness, and interleaved fingers of IDTs of the low band series resonators and the high band shunt resonators are disposed on respective diaphragms having thicknesses intermediate the first thickness and the second thickness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.