Single-crystal bulk acoustic wave resonator and method of making thereof
US11817839B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 2020 |
| Grant date | Nov 14, 2023 |
| Priority date | — |
| Expiry date | Aug 25, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2003/025
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A single-crystal bulk acoustic wave resonators with better performance and better manufacturability and a process for fabricating the same are described. A low-acoustic-loss layer of one or more single-crystal and/or poly-crystal piezoelectric materials is epitaxially grown and/or physically deposited on a surrogate substrate, followed with the formation of a bottom electrode and then a support structure on a first side of the piezoelectric layer. The surrogate substrate is subsequently removed to expose a second side of the piezoelectric layer that is opposite to the first side. A top electrode is then formed on the second side of the piezoelectric layer, followed by further processes to complete the BAW resonator and filter fabrication using standard wafer processing steps. In some embodiments, the support structure has a cavity or an acoustic mirror adjacent the first electrode layer to minimize leakage of acoustic wave energy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.