Abstract

A bulk acoustic wave filter composed of piezoelectric thin-film resonators has many features superior to those of other small filters such as a surface acoustic wave (SAW) filter and a ceramic filter. A high-Q factor and low loss are big advantages for a film bulk acoustic resonator (FBAR). The electrode material that is selected is very important for maintaining a high-Q and appropriate coupling factor. An analysis of the effects of acoustic impedance on AlN-based FBAR performance is described. The electromechanical coupling factor (k2) and filter loss were found to be influenced by acoustic impedance and to be mainly dominated by Young's modulus. Ru was found by analysis and experiments to be a suitable material for the electrode. Finally, a 2 GHz wide band code division multiple access (WCDMA) filter was demonstrated to have a good performance.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.