A flexural plate wave (FPW) device with low insertion loss and high electromechanical coupling coefficient

摘要

flow rate) were modulated to achieve a high C-axis (002) orientated piezoelectric ZnO film and a high electromechanical coupling factor of the FPW device. Under the optimized sputtering condition in this work, a high X-Ray diffraction (XRD) intensity (20,944 a.u) of the ZnO thin-film at 34.2° diffraction angle and a very narrow full-width at half-maximum (FWHM = 0.573°) can be demonstrated. Furthermore, as the optimized ZnO layer integrated on the bulk-micromachined FPW sensor, very low insertion loss (14dB) and high electromechanical coupling coefficient (11.62%) can be obtained at a very low operation frequency.