Experimental verification of stress compensation in the SBTC-cut

The SBTC-cut (stress compensated for the B-mode and temperature compensated for the C-mode) was first predicted in 1981 based on theoretical calculations for the force-frequency effect in thickness-shear quartz resonators. The authors have verified experimentally the stress compensation feature for the fast thickness shear mode of vibration of SBTC-cut quartz resonators. The first set of experimental results consists of measurements made on biconvex contoured, disc resonators of orientation in the neighborhood of SBTC-cut as well as on a RT-cut resonator with a different radius of curvature for the contoured faces. For the resonator design used in the cylindrical probe structure, the motional resistance for the B-mode of vibration was approximately 12% of that of the C-mode. In addition, experimental data were obtained on the temperature dependence of the planar stress coefficient and pressure dependence of the frequency-temperature characteristic for both the thickness-shear modes of the SBTC-cut