New modeling of TFBAR and on-wafer inductor effects on the TFBAR ladder filter performance

Author

Kim, Jong-Soo ; Yong-Dae Kim ; Gu, Yong-Dae Kim Myeong-Gweon ; Yook, Song-Gwan

Author_Institution

Dept. of Electr. & Electron. Eng., Yonsei Univ., Seoul, South Korea

Volume

1

fYear

2004

fDate

6-11 June 2004

Firstpage

379

Abstract

In this paper, a new modeling methodology for thin film bulk acoustic resonators (TFBAR) is presented and the formulations for each lumped element in the model are also presented. The proposed model has three optimization variables which is half of the modified Butterworth-Van Dyke (MBVD) model, and as a result the curve fitting for the measured data is much faster and more accurate than any other conventional models. In addition, two types TFBAR ladder filters are designed and fabricated to analyze the effects of on-wafer inductor integration. Fabricated on-wafer spiral inductor reveals the Q-factor of 9 at 2 GHz and the inductor integrated filters have approximately 10 to 12 dB out-of-band rejection improvement compared to the original filters.

Keywords

Butterworth filters; acoustic resonator filters; bulk acoustic wave devices; curve fitting; inductors; ladder filters; thin film devices; Q-factor; TFBAR ladder filters; TFBAR modeling; acoustic resonator modeling; curve fitting; inductor integrated filters; inductor integration effects; ladder filter designing; ladder filter fabrication; ladder filter performance; lumped element formulation; modified Butterworth-Van Dyke model; on-wafer inductor effects; on-wafer inductor integration; on-wafer spiral inductor; optimization variables; out-of-band rejection improvement; thin film bulk acoustic resonators; Air gaps; Biomembranes; Capacitors; Design optimization; Equivalent circuits; Film bulk acoustic resonators; Inductors; Piezoelectric materials; Resonator filters; Spirals;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Symposium Digest, 2004 IEEE MTT-S International

ISSN

0149-645X

Print_ISBN

0-7803-8331-1

Type

conf

DOI

10.1109/MWSYM.2004.1335901

Filename

1335901