Film bulk acoustic resonator filters with a coplanar waveguide
US7187254B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 2001 |
| Grant date | Mar 6, 2007 |
| Priority date | — |
| Expiry date | Sep 5, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/568
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Multiple thin film bulk acoustic resonators (10, 11) configured in series (10) and parallel (11) within a coplanar waveguide line structure provides a compact ladder filter. The resonators (10, 11) are formed over an opening (28) in a substrate (20) and connected to associated circuitry by one or more transmission lines formed on the substrate (20). The arrangement of the resonators (10, 11) between the ground and signal lines of a coplanar line structure provides a means of minimising the area of the filter. Embedding a ladder filter within the coplanar transmission line structure eliminates the need for wire bonds, thus simplifying fabrication. Embodiments for 2×2, and hither order filters are described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.