PH measurements with ZvO based Surface Acoustic Wave Resonator

Author

Tang, R. ; Qiu, X. ; Zhu, J. ; Oiler, J. ; Huang, H. ; Wang, H. ; Yu, H.

Author_Institution

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

fYear

2011

fDate

5-9 June 2011

Firstpage

1132

Lastpage

1135

Abstract

This paper investigated pH measurements using ZnO based Surface Acoustic Wave Resonator (SAW). The resonant frequency of the SAW decreased as pH changed from 7 to 2 (acid region) or from 7 to 12 (alkaline region). The detection limits were 0.03 and 0.02 pH change, respectively, which were comparable to commercial pH meters. The interaction between hydronium (H₃O⁺) or hydroxide (OH^-) and ZnO was proposed to be responsible for the frequency drop. Both hydronium and hydroxide can increase the conductivity of the ZnO film, resulting in the resonant frequency decrease due to the acoustoelectric effect.

Keywords

II-VI semiconductors; chemical sensors; pH measurement; surface acoustic wave resonators; zinc compounds; PH measurements; ZnO; acoustoelectric effect; resonant frequency; surface acoustic wave resonator; Films; Resonant frequency; Sensors; Surface acoustic waves; Surface impedance; Zinc oxide; ZnO; acoustoelectric effect; pH; surface acoustic wave resonator;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Sensors, Actuators and Microsystems Conference (TRANSDUCERS), 2011 16th International

Conference_Location

Beijing

ISSN

Pending

Print_ISBN

978-1-4577-0157-3

Type

conf

DOI

10.1109/TRANSDUCERS.2011.5969292

Filename

5969292