| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a quartz crystal unit including a microfabricated tuning fork type bent quartz crystal vibrating chip which vibrates in a bending mode of fundamental wave and opposite phase, reduces equivalent series resistance, improves a quality coefficient Q factor and further reduces a capacitance ratio, and a method of manufacturing a quartz crystal oscillator. <P>SOLUTION: Grooves 146-149 are formed on upper surfaces and lower surfaces of tuning fork arms 143, 144 of a tuning fork type bent quartz crystal vibrating chip 160, electrodes 151, 152 and electrodes 155, 156 are formed on side surfaces of the grooves, and electrodes 150, 153 and electrodes 154, 157 having different polarities are disposed on side surfaces of the tuning fork arm opposite to the side surfaces. A ratio of a length of the grooves to a full length of the tuning fork type bent quartz crystal vibrating chip is settled within the range of 0.2 to 0.78, and a ratio of thickness of the grooves to thickness of the tuning fork arms comprising grooves is smaller than 0.79. The tuning fork type bent quartz crystal vibrating chip is fixed to a fixing part 159 of a case 165 by a conductive adhesive 161, a cover 163 is bonded, an oscillation frequency is adjusted in vacuum and after the adjustment, a through-hole 167 provided in the case is sealed with a metal 166 in vacuum. <P>COPYRIGHT: (C)2009,JPO&INPIT |
