title: A thin-film bulk acoustic resonator and filter with optimal edge shapes for mass production.
abstract: The manufacturing conditions of a thin-film bulk acoustic resonator (FBAR) filter were investigated to obtain a high Q factor which is stable for mass production. The FBAR consist of patterned electrodes and piezoelectric films. In this study, the influence of edge shape of the films on the anti-resonance characteristics was investigated using a numerical method. Optimized shape was applied to a 2.5-GHz band resonator and filter. As a result, significant improvement of the Q factor and the insertion loss was confirmed.
authors.affiliation: Microdevice R&D Department, Taiyo Yuden Co., Ltd., Akashi 674-8555, Japan. hara@nanosys.mech.tohoku.ac.jp
authors.forename: Motoaki
authors.initials: M
authors.lastname: Hara
authors.forename: Masanori
authors.initials: M
authors.lastname: Ueda
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Satoh