Acoustic resonator filter with reduced electromagnetic influence due to die substrate thickness
US6377137B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 11, 2000 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | Sep 27, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/42
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A plurality of acoustic resonators are manufactured in a batch process by forming cavities in a substrate and filling the cavities with a sacrificial layer. An FBAR membrane comprising a bottom electrode, a piezoelectric layer, and a top electrode is formed over each cavity and the sacrificial layer. The substrate is then thinned and the substrate is separated into a plurality of dice using a scribe and break process. The sacrificial layer is then removed and the FBAR filter is mounted in a package with thermal vias being thermal communication with underside of the FBAR filter. The production method improves thermal properties by increasing the efficiency of heat dissipation from the FBAR filter. In addition, electromagnetic interference is decreased by reducing the distance between a primary current flowing over the surface of the FBAR filter and an image current flowing in a ground plane beneath the FBAR filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.