Design of SC Cut 10 MHz H.Q. Crystals with G. Sensitivity Better Than 2.10(-10)/G,

Abstract : Several theoretical and experimental studies on the force-frequency effect have shown that the g sensitivity of a crystal resonator is directly related to the location and structure of the mounting support. This work has lead to the definition of a new design of crystal resonator having low sensitivity. The effects of both surface and body forces applied to the vibrating part of the crystal must be considered. In this paper, the details of this new design are presented. Statistical results show that g sensitivity between 3.10 to the minus 11th power/g and 2.10 to the minus 10th power/g on the worst axis are currently obtained on an industrial basis. These values are measured by a 2 g tip over test in all directions either with Phase Modulated Reflectometer (which are also described at 5 and 10 MHz) or in classical oscillators.