Fabrication of 5GHz band film bulk acoustic wave resonators using ZnO thin film

Author

Kubo, Ryuichi ; Fujii, Hidetoshi ; Kawamura, Hideki ; Takeuchi, Masaki ; Inoue, Kazuhiro ; Yoshino, Yukio ; Makino, Takahiro ; Arai, Seiichi

Author_Institution

Res. & Dev. Div., Murata Manuf. Co. Ltd., Kyoto, Japan

Volume

1

fYear

2003

fDate

5-8 Oct. 2003

Firstpage

166

Abstract

We successfully fabricated 5GHz band thin film bulk acoustic wave (BAW) resonators using ZnO thin film. Two types of BAW resonators utilizing fundamental resonance and secondary harmonics were examined. In the fundamental mode resonator, the quality factor (Q factor) and the effective electromechanical coupling coefficient (k_teff²) were realized at 1000 and 6.7%, respectively. These values for the secondary mode resonator were 700 and 4.7%, respectively. Combining four fundamental mode resonators as a ladder type piezoelectric filter, the bandwidth at 3 dB was achieved to be 191 MHz at 4.9 GHz. Even with the filter using the secondary mode resonator, the bandwidth was 130 MHz at 5.2 GHz.

Keywords

II-VI semiconductors; Q-factor; acoustic resonance; acoustic resonators; bulk acoustic wave devices; crystal filters; crystal resonators; harmonics; ladder filters; semiconductor thin films; zinc compounds; 130 GHz; 191 GHz; 3 dB; 4.9 GHz; 5 GHz; 5.2 GHz; ZnO; ZnO thin film; electromechanical coupling coefficient; fundamental mode resonators; fundamental resonance; ladder type piezoelectric filter; secondary harmonics; secondary mode resonator; thin film bulk acoustic wave resonators; Acoustic waves; Bandwidth; Fabrication; Film bulk acoustic resonators; Power harmonic filters; Q factor; Resonance; Resonator filters; Transistors; Zinc oxide;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics, 2003 IEEE Symposium on

Print_ISBN

0-7803-7922-5

Type

conf

DOI

10.1109/ULTSYM.2003.1293380

Filename

1293380