Characteristics of one-port surface acoustic wave resonator fabricated on ZnO/6H-SiC layered structure

摘要

Characteristics of one-port surface acoustic wave (SAW) resonators fabricated on ZnO/6H-SiC layered structure were investigated experimentally and theoretically. Phase velocities (V-p), electromechanical coupling coefficients (K-2), quality factors (Q), and temperature coefficients of frequency (TCF) of Rayleigh wave (0th mode) and first-and second-order Sezawa wave (1st and 2nd modes, respectively) for different piezoelectric film thickness-to-wavelength (h(ZnO)/lambda) ratios were systematically studied. Results demonstrated that one-port SAW resonators fabricated on the ZnO/6H-SiC layered structure were promising for high-frequency SAW applications with moderate K-2 and TCF values. A high K-2 of 2.44% associated with a V-p of 5182 m s(-1) and a TCF of -41.8 ppm/degrees C was achieved at h(ZnO)/lambda = 0.41 in the 1st mode, while a large V-p of 7210 m s(-1) with a K-2 of 0.19% and a TCF of -36.4 ppm/degrees C was obtained for h(ZnO)/lambda = 0.31 in the 2nd mode. Besides, most of the parameters were reported for the first time and will be helpful for the future design and optimization of SAW devices fabricated on ZnO/6H-SiC layered structures.