In this study, acoustic sensors were formed by depositing a zinc oxide (ZnO) thin film on a silicon dioxide/silicon(SiO/Si) substrate using radio frequency (RF) planar-magnetron sputtering method. The results showed higher substrate temperatures and higher RF powers enhanced C-axis oriented structure of the Zno thin film and optimized the ZnO thin film acoustic property. The frequency spectrum measurement on the acoustic sensor underwater involved three peaks at frequencies 640 KHz, 2.4 MHz and 2.9 MHz, respectively. Sensitivity reached to -132.02 dBrelv/ upa. The results indicated that under the pressure of acoustic frequencies the sensor response was directly proportional to pressure and, therefore, can be actually utilized in underwater sounding tests.
Chang, C.C. and Chang, J.H.
"A Study on Fabrication of Zinc Oxide thin Film Acoustic Sensors,"
Journal of Marine Science and Technology: Vol. 4:
1, Article 17.
Available at: https://jmstt.ntou.edu.tw/journal/vol4/iss1/17