Temperature stability of surface acoustic wave resonators on in-plane rotated 33° Y-cut quartz

ST-cut quartz has been widely used in surface acoustic wave (SAW) devices due to its good temperature stability: However, ST-cut SAW devices are still not as temperature stable as AT-cut quartz. Hence new SAW resonators with better temperature stability are needed. We present surface acoustic wave resonators on the in-plane rotated 33degrees Y-cut quartz with improved temperature stability. We calculated the frequency temperature characteristics of Rayleigh waves using the finite element method under the condition of Euler angle (0, 123, 39-44). The second-order temperature coefficients of less than -1:5 x 10(-8)/degreesC(2) were achieved by calculations and experiments. Compared with the second-order temperature coefficients of ST-cut quartz (-3.4 x 10(-8)/degreesC(2)), these values are more than 50% smaller. The fabricated SAW resonators have good crystal impedance (resonance impedance) and Q-value.