Method for fabricating a resonator having an acoustic mirror
US5873154A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 1996 |
| Grant date | Feb 23, 1999 |
| Priority date | — |
| Expiry date | Oct 17, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/42
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A Thin Film Bulk Acoustic Wave Resonator (FBAR), comprising a top electrode layer, a substrate, an acoustic mirror that is formed atop the substrate, and a piezoelectric layer that is formed between the top electrode layer and the acoustic mirror. The acoustic mirror is comprised of a plurality of stacked layers. One of the stacked layers forms a bottom electrode layer. At least another one of the stacked layers comprises a polymer material. The piezoelectric produces vibrations in response to a voltage being applied between the top electrode and the bottom electrode. The acoustic mirror acoustically isolates these vibrations from the substrate. The polymer material is preferably an electronic grade polymer and has a capability of withstanding a deposition of the piezoelectric layer at an elevated temperature. The layers forming the acoustic mirror which do not comprise the polymer material comprise a high acoustic impedance material such as, by example, tungsten (W). The polymer material can be spun on the substrate during fabrication of the FBAR.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.