| 摘要 |
PROBLEM TO BE SOLVED: To prevent an oscillation characteristics from deteriorating due to a change with the lapse of time. SOLUTION: In this method, production of a crystal oscillator where silver electrodes are formed on both sides of a crystal plate is performed. In this case, silver is vapor deposited on the crystal plate in a vacuum chamber 14, a silver electrode 12 is formed, and an insulated film 13 such as an oxidized silicon or the like is stacked on the silver electrode 12. In a process of accumulating an insulation film 13' on the other side (or a process of eliminating the insulation film 13' accumulated thick by a dry etching), the frequency of the crystal oscillator 25 is measured continuously and frequency adjustment is performed by stopping the accumulation (or an elimination) at a time when the measured frequency matches the set frequency. Since both the sides of the silver electrodes 12 and 12' are protected by the insulation films 13 and 13', the change with the laps of time in weight of the silver electrodes 12 and 12' is extremely small and it is possible to prevent the deterioration of oscillation characteristic. |
