Measurement of piezoelectric and elastic stiffness constants of /spl beta/ phase quartz at high temperature region

This paper presents the electromechanical properties of /spl beta/ quartz in a higher temperature region than the /spl alpha/-/spl beta/ transition temperature of 573/spl deg/C. The piezoelectric and elastic constants were estimated from the resonance characteristics using an off-axial plate such as a rotated Y cut plate. The piezoelectric constant e/sub 14/ of /spl beta/ quartz is slightly larger than that for /spl alpha/ quartz of 0.0406 C/m/sup 2/. It was found that elastic loss of /spl beta/ quartz is relatively low in the high temperature region above 700/spl deg/C. A very high resonance quality factor was obtained, ie 15,000 at 600/spl deg/C and 11,000 at 700/spl deg/C. /spl beta/ quartz is useful for high performance resonators in the high temperature region between 600/spl deg/C and 1,000/spl deg/C.