Self-aligned lateral field excitation film acoustic resonator with very large electromechanical coupling [FBAR]

Author

Pang, Wei ; Yu, Hongyu ; Kwon, Jae Wan ; Zhang, Hao ; Kim, Eun Sok

Author_Institution

Dept. of Electr. Eng.-Electrophys., Univ. of Southern California, Los Angeles, CA, USA

fYear

2004

fDate

23-27 Aug. 2004

Firstpage

558

Lastpage

561

Abstract

This paper describes a self-aligned lateral-field excitation (LFE) film bulk acoustic resonator (FBAR) that exhibits an electromechanical coupling coefficient (K_t²) of 10% at 4.1 GHz, albeit a relatively low Q of 35. The unique features of this resonator include: (1) improved energy trapping structure that does not require an electrode gap close to a micron; and (2) a simple two-mask self-aligned fabrication process that eliminates misalignment between the piezoelectric ZnO and the metal electrode.

Keywords

Q-factor; acoustic microwave devices; acoustic resonators; bulk acoustic wave devices; zinc compounds; 4.1 GHz; Q factor; ZnO; electrode gap; electromechanical coupling coefficient; energy trapping structure; film bulk acoustic resonator; piezoelectric layer/metal electrode alignment; self-aligned lateral field excitation FBAR; two-mask self-aligned fabrication process; Acoustic waves; Bandwidth; Electrodes; Fabrication; Film bulk acoustic resonators; Mobile communication; Piezoelectric films; Resonant frequency; Resonator filters; Zinc oxide;

fLanguage

English

Publisher

ieee

Conference_Titel

Frequency Control Symposium and Exposition, 2004. Proceedings of the 2004 IEEE International

ISSN

1075-6787

Print_ISBN

0-7803-8414-8

Type

conf

DOI

10.1109/FREQ.2004.1418519

Filename

1418519