摘要 |
A piezoelectric vibrator element is shaped by photo-etching techniques from a quartz crystal wafer. Film electrodes and masses for frequency adjustment are applied by first depositing a layer of chromium and then a layer of gold on the element by vacuum depositing or sputtering. The element is then kept in a high vacuum of at least 10-5 torr and at a high temperature of 300 DEG C to fix the depositions on the element and eliminate distortion. To adjust the frequency, a portion of the metal mass is removed by a laser beam, after which the element is kept in a high vacuum at high temperature to affix securely to the element any bits of metal that may have condensed during the removing step. . |