Transversely-excited film bulk acoustic resonators with two-layer electrodes having a narrower top layer
US11909381B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 2020 |
| Grant date | Feb 20, 2024 |
| Priority date | — |
| Expiry date | Sep 10, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2003/023
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An acoustic resonator device, filter devices, and methods of making the same. An acoustic resonator device includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces, where the back surface is 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. The device further includes an interdigital transducer formed on the front surface of the piezoelectric plate, where interleaved fingers of the IDT disposed on the diaphragm are configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode in the diaphragm. The interleaved fingers include a first layer adjacent the diaphragm and a second layer over the first layer, the second layer having a narrower width than the first layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.