Piezoelectric vibrator, oscillator, electronic apparatus, and radio-controlled timepiece

A method for producing piezoelectric vibrators, comprising:

• (a) defining a plurality of first substrates on a first wafer and a plurality of second substrates on a second wafer;
• (b) forming three electrode patterns electrically isolated from one another on a respective at least some of the first substrates;
• (c) forming a bump in electrical contact with each of the three electrode patterns on a respective at least some of the first substrates on which the three electrode patterns are formed;
• (d) forming a plurality of piezoelectric vibrating reeds each having a tuning fork shape consisting of a base and a pair of arms connected to the base, three mount electrodes being formed on the base so as to be electrically isolated from one another, wherein the three mount electrodes comprise a pair of mount electrodes for receiving electricity to vibrate the arms and an auxiliary mount electrode;
• (e) mounting the piezoelectric vibrating reed on a respective at least some of the first substrates on which the three bumps are formed, in such a manner that the three mount electrodes are bonded, respectively, with the three bumps formed on the three electrode patterns;
• (f) layering the first and second wafers such that at least some of the first substrates substantially coincide respectively with at least some of the corresponding second substrates, wherein the piezoelectric vibrating reed is secured in a cavity formed between a respective at least some of the coinciding first and second substrate pairs;
• (g) hermetically bonding at least some of the coinciding first and second substrate pairs;
• (h) cutting off from the first and second wafers a respective at least some of the hermetically bonded first and second substrate pairs.