Tuning fork shaped crystal oscillator and method of fabrication thereof

Abstract

The present invention provides a tuning fork shaped oscillator, an angular velocity sensor element, and an angular velocity sensor with improved breaking strength with respect to CI and drive power, CI stability, and frequency stability. The present invention relates to a tuning fork shaped crystal oscillator of a configuration wherein two tuning fork shaped crystal elements that have been formed by wet etching during the process of forming the external shape of a tuning fork, in such a manner that the longitudinal direction of the tuning fork is aligned on the Y-axis of the crystalline axes (XYZ) and also the lateral direction thereof is aligned on the X-axis, are bonded together with the ±X-axis directions thereof oriented in opposite directions; and the right side surface of each of the two tuning fork shaped crystal elements is the +X face of the crystal when the two tuning fork shaped crystal elements are viewed in an upright attitude.

1 . A tuning fork shaped crystal oscillator, wherein two tuning fork shaped crystal elements formed by wet etching during formation of the external shape of a tuning fork, in such a manner that the longitudinal direction of the tuning fork is aligned on the Y-axis of the crystalline axes (XYZ) and the lateral direction thereof is aligned on the X-axis, are bonded together with the ±X-axis directions thereof oriented in opposite directions; the right side surface of each of said two tuning fork shaped crystal elements being the +X face of the crystal when said two tuning fork shaped crystal elements are viewed in an upright orientation from each Z-axis direction.  
   
   
       2 - 5 . (canceled)  
   
   
       6 . The tuning fork shaped crystal oscillator as defined by  claim 1 , wherein said tuning fork shaped crystal oscillator is provided with a drive electrode for exciting the tuning fork into resonance and a sensor electrode for detecting electrical charge due to the Coriolis force and functions as an angular velocity sensor element.  
   
   
       7 - 9 . (canceled)  
   
   
       10 . The tuning fork shaped crystal oscillator as defined by  claim 6 , further comprising an oscillation circuit for exciting the tuning fork of said angular velocity sensor element into resonance, and a synchronization detection circuit for detecting electrical charge from a sensor electrode of said tuning fork shaped crystal oscillator.  
   
   
       11 . (canceled)