Electrode structure of bulk acoustic resonator with edge air gap and fabrication method thereof
US11575360B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 21, 2022 |
| Grant date | Feb 7, 2023 |
| Priority date | — |
| Expiry date | Mar 21, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/176
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An electrode structure of a resonator and a fabrication method for the electrode structure of the resonator are provided. The electrode structure includes a piezoelectric layer. An electrode metal layer, a dielectric layer, a protrusion/frame metal layer and an etching passivation layer are sequentially arranged above the piezoelectric layer. An air gap is formed between the dielectric layer and the protrusion/frame metal layer, and the air gap is located at an electrode edge. Through the air gap between the dielectric layer and the protrusion/frame metal layer above the piezoelectric layer, an electrode protrusion/frame structure of the resonator with an edge air gap is formed, which serves as an electrode part. When the resonator is working, through the air gap, a transverse sound wave can be reflected back to the resonator and be bound in a resonator body. This greatly increases the Q factor and working performance of the resonator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.