Improvement of crystallinity of ZnO thin film and electrical characteristics of film bulk acoustic wave resonator by using Pt buffer layer

被引：22

作者：

Yamada, H ^{[1
]}

Ushimi, Y ^{[1
]}

Takeuchi, M ^{[1
]}

Yoshino, Y ^{[1
]}

Makino, T ^{[1
]}

Arai, S ^{[1
]}

机构：

[1] Murata Mfg Co Ltd, Kyoto, Japan

来源：

VACUUM | 2004年 / 74卷 / 3-4期

关键词：

ZnO; buffer layer; BAW; crystallinity; piezoelectric; electrical characteristics;

D O I：

10.1016/j.vacuum.2004.01.061

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Crystallinity of ZnO thin film for film bulk acoustic wave (BAW) resonator has been successfully improved by using Pt/Al bottom electrode. The lattice mismatch of ZnO c-plane and Pt (1 1 1) plane is as small as 1.4% so that we could obtain good crystallinity ZnO film on Pt surface. The effective electromechanical coupling coefficient (kt(eff)(2)) of the BAW resonator that we fabricated with AI/ZnO/Pt/Al/SiO2 structure is 5.6%. It is larger than that of Al/ZnO/Al/SiO2 structure BAW resonator, whose value is 4.9%. The kt(eff)(2) is improved by using the Pt/Al bottom electrode without decreasing the quality factor. The kt(eff)(2) of BAW resonator strongly depends on the crystallinity of ZnO film. Using Pt buffer layer to protect Al electrode from its oxidation is very effective to improve the crystallinity of ZnO film and the kt(eff)(2) of BAW resonator. eff (C) 2004 Published by Elsevier Ltd.

引用

页码：689 / 692

页数：4

共 8 条

[1] PIEZOELECTRIC PROPERTIES OF ZINC-OXIDE FILMS ON GLASS SUBSTRATES DEPOSITED BY RF-MAGNETRON-MODE ELECTRON-CYCLOTRON-RESONANCE SPUTTERING SYSTEM [J].