An Intrinsically Switchable FBAR Filter Based on Barium Titanate Thin Films

Author

Zhu, Xinen ; Lee, Victor ; Phillips, Jamie ; Mortazawi, Amir

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., Univ. of Michigan, Ann Arbor, MI

Volume

19

Issue

6

fYear

2009

fDate

6/1/2009 12:00:00 AM

Firstpage

359

Lastpage

361

Abstract

A switchable thin film bulk acoustic wave resonator (FBAR) filter based on barium titanate (BTO) thin films is reported for the first time. BTO is a ferroelectric material which possesses electrostriction, giving the filter the ability to be placed in either an on state or an off state by changing the applied dc bias voltage. A 1.5 stage ladder type bandpass filter using BTO FBARs has been designed, fabricated, and measured. The application of a 15 V dc bias results in the filter being place in an on state with a center frequency of 2.14 GHz, a 40 MHz bandwidth and 6.2 dB of insertion loss. Conversely, the application of a - 3 V dc bias results in the filter being placed in an off state with 15 dB of rejection. This filter is very compact with dimensions of 40 mum by 80 mum.

Keywords

acoustic resonator filters; band-pass filters; barium compounds; ferroelectric devices; ferroelectric thin films; BaTiO₃; applied dc bias voltage; bandpass filter; barium titanate thin films; dc bias; electrostriction; ferroelectric material; insertion loss; loss 6.2 dB; off state; switchable thin film bulk acoustic wave resonator filter; voltage -3 V; voltage 15 V; Barium titanate (BTO); bulk acoustic wave devices; ferroelectric thin films; film bulk acoustic wave resonator (FBAR); switchable filters;

fLanguage

English

Journal_Title

Microwave and Wireless Components Letters, IEEE

Publisher

ieee

ISSN

1531-1309

Type

jour

DOI

10.1109/LMWC.2009.2020013

Filename

4982547