Focusing transformers/filters in isotropic/anisotropic piezoelectrics
US10979018B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 2019 |
| Grant date | Apr 13, 2021 |
| Priority date | — |
| Expiry date | Nov 26, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/02543
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A focusing interdigital transducer (IDT) and corresponding single- and dual-port piezoelectric devices are disclosed. The focusing interdigital transducer, which generates Lamé acoustic waves, permits operation at significantly higher frequencies than those possible with traditional IDTs. The focusing IDT employs multiple arced fingers formed both above and below the piezoelectric layer to improve coupling efficiency by coupling through both the e31 and e33 piezoelectric coefficients to the piezoelectric layer. By optimizing both anchor design and location, acoustic wave losses are minimized, thereby improving the device's quality factor Q. Through proper bus design and selection of the number of IDT fingers, a device's impedance can be tuned for a given application. The focusing IDTs may be used in single-port filter devices and dual-port transformer devices. The single- and dual-port devices may operate at a single frequency, at two frequencies, or over a band of frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.