TUNING FORK TYPE BIMORPH PIEZOELECTRIC VIBRATOR, VIBRATING GYRO-MODULE USING THE VIBRATOR, AND METHOD FOR MANUFACTURING THE TUNING FORK TYPE BIMORPH PIEZOELECTRIC VIBRATOR

摘要

Provided is a tuning fork type bimorph piezoelectric vibrator, which can improve the temperature characteristics of a detuned frequency and can detect a rotating angular velocity stably and precisely at a low cost. The tuning fork type bimorph piezoelectric vibrator (100) has an intermediate metal film (112) formed on a junction face by junctioning two piezoelectric portions (110a, 110b) confronting each other in a polarizing direction. A first slit (120) is formed to form tuning fork type leg portions (122a, 122b) and a base portion (124). Second slits (130a, 130b) are formed on one principal face (or the surface of one piezoelectric portion (110a)) having a surface metal film, thereby to form driving and detecting electrodes (140, 142a, 142b). The tuning fork type bimorph piezoelectric vibrator has no back metal film at such a portion of its other principal face (or the surface of the other piezoelectric portion (110b)) as is exposed to a predetermined or higher stress at least at its action time, thereby to improve the temperature characteristics of the detuned frequency.