The effects of relative humidity and reducing gases on the temperature coefficient of resonant frequency of ZnO based film bulk acoustic wave resonator

Author

Qiu, Xiaotun ; Wang, Ziyu ; Zhu, Jie ; Oiler, Jon ; Tang, Rui ; Yu, Cunjiang ; Yu, Hongyu

Author_Institution

Sch. of Electr., Comput. & Energy Eng., Arizona State Univ., Tempe, AZ, USA

Volume

57

Issue

9

fYear

2010

fDate

9/1/2010 12:00:00 AM

Firstpage

1902

Lastpage

1905

Abstract

This study describes the influence of relative humidity (RH) and reducing gases on the temperature coefficient of resonant frequency (TCF) of ZnO-based film bulk acoustic wave resonator (FBAR). Upon exposure to moisture or reducing gases, the TCF of FBAR decreased. Water molecules can replace adsorbed oxygen on the ZnO surface. This process was less effective at high temperature, resulting in a lower TCF in high RH. Reducing gases, such as acetone, can reduce the density of ZnO through reaction with the adsorbed oxygen, leading to a lower TCF.

Keywords

II-VI semiconductors; acoustic resonators; adsorbed layers; bulk acoustic wave devices; humidity; oxygen; reduction (chemical); semiconductor thin films; thin film devices; water; wide band gap semiconductors; zinc compounds; FBAR; H₂O; O₂; TCF; ZnO; acetone; adsorbed oxygen; film bulk acoustic wave resonator; high temperature; moisture; reducing gases; relative humidity; resonant frequency temperature coefficient; Film bulk acoustic resonators; Films; Gases; Humidity; Resonant frequency; Zinc oxide;

fLanguage

English

Journal_Title

Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on

Publisher

ieee

ISSN

0885-3010

Type

jour

DOI

10.1109/TUFFC.2010.1637

Filename

5585471