Development of 4 GHz bulk acoustic wave resonators by sputtered Pb(Mn,Nb)O3-Pb(Zr,Ti)O3 thin films

Author

Yamauchi, N. ; Shirai, T. ; Yoshihara, T. ; Hayasaki, Y. ; Matsushima, T. ; Kanno, I. ; Wasa, Kiyotaka

Author_Institution

Adv. Technol. Dev. Lab., Panasonic Electr. Works, Co., Ltd., Kadoma

fYear

2008

fDate

2-5 Nov. 2008

Firstpage

1920

Lastpage

1923

Abstract

The 4 GHz bulk acoustic wave (BAW) resonators have been fabricated by thin films of Pb(Zr,Ti)O₃ based ternary perovskite compounds. The Pb(Mn_1/3Nb_2/3)O₃-Pb(Zr,Ti)O₃ (PMnN-PZT) thin films were deposited on (100)MgO substrates by RF magnetron sputtering. The PMnN-PZT thin films showed tetragonal crystal structure and highly (001) orientation. The surface roughness of the thin films was about 2 nm. The cross section TEM image of PMnN-PZT thin films showed single c-domain/ single crystal structure. The bulk acoustic wave (BAW) resonators composed by PMnN-PZT thin films were fabricated by MEMS technology. The RF properties of the resonator were evaluated by VNA (Vector Network Analyzer). The BAW resonator by 0.1PMnN-0.9PZT(55/45) thin film exhibited high electro-mechanical coupling constant kt and high Q value at 3.87GHz. Values of k_t, Q, and k_t ²Q were found to be 0.56, 185 and 58, respectively. These values are highest, in our knowledge, comparing with those of previously reported PZT-BAW resonators.

Keywords

acoustic resonators; bulk acoustic wave devices; crystal orientation; lead compounds; micromechanical resonators; piezoelectric thin films; sputtered coatings; BAW resonator; MEMS technology; MgO; Pb(MnNb)O₃-Pb(ZrTi)O₃; RF magnetron sputtering; TEM image; VNA; bulk acoustic wave resonator; electro-mechanical coupling constant; frequency 4 GHz; sputtered thin film; surface roughness; ternary perovskite compounds; vector network analyzer; Acoustic waves; Micromechanical devices; Niobium; Radio frequency; Rough surfaces; Sputtering; Substrates; Surface acoustic waves; Surface roughness; Transistors; BAW resonato; MEMS; PMnN-PZT; Single crystal; Thin films;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 2008. IUS 2008. IEEE

Conference_Location

Beijing

Print_ISBN

978-1-4244-2428-3

Electronic_ISBN

978-1-4244-2480-1

Type

conf

DOI

10.1109/ULTSYM.2008.0473

Filename

4803387