Method for fabricating a thin film bulk acoustic wave resonator (FBAR) on a glass substrate
US6839946B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 2002 |
| Grant date | Jan 11, 2005 |
| Priority date | — |
| Expiry date | Jan 15, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49165
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method for fabricating a Thin Film Bulk Acoustic Wave Resonator (FBAR). The method comprises the steps of: (A) forming a sacrificial layer comprising one of a metal and a polymer over a selected portion of a substrate; (B) forming a protective layer on the sacrificial layer and on selected portions of the substrate; (C) forming a bottom electrode layer on a selected portion of the protective layer; (D) forming a piezoelectric layer on a selected portion of the bottom electrode layer and on a selected portion of the protective layer; (E) forming a top electrode on a selected portion of the piezoelectric layer; and (F) removing the sacrificial layer to form an air gap. The use of a metal or a polymer material to form sacrificial layers has several advantages over the use of zinc-oxide (ZnO) to form such layers. In accordance with a further aspect of the invention, an FBAR is provided which includes a glass substrate. The use of glass to form substrates offers several advantages over the use of other materials to form substrates. By example, most types of glass are less expensive than semiconductor materials, and exhibit low permittivity characteristics, and low parasitic capacitanc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.