PIEZOELECTRIC VIBRATION PIECE, PIEZOELECTRIC VIBRATOR MANUFACTURING METHOD, PIEZOELECTRIC VIBRATOR, OSCILLATOR, ELECTRONIC EQUIPMENT, AND RADIO CLOCK

摘要

PROBLEM TO BE SOLVED: To appropriately improve the accuracy of oscillation frequency adjustment.SOLUTION: Weight metal films 21, each consisting of at least three kinds of films differing in mass per unit area including a coarse adjustment film 21a, a coarse-and-fine adjustment film 21b and a fine adjustment film 21c, are formed on different positions on the surfaces of vibration arms 10 and 11 of a piezoelectric vibration piece. Before the piezoelectric vibration piece is housed in a package, it is subjected to a coarse adjustment step in which laser light is irradiated on the coarse adjustment films 21a of the weight metal films 21 to remove part of the coarse adjustment films 21a. After the piezoelectric vibration piece is housed in a package, it is subjected to a coarse-and-fine adjustment step in which laser light is irradiated on the coarse-and-fine adjustment films 21b of the weight metal films 21 to remove part of the coarse-and-fine adjustment films 21b and a fine adjustment step in which laser light is irradiated on the fine adjustment films 21c to remove part of the fine adjustment films 21c.