Methods for manufacturing piezoelectric devices

Abstract

Methods are provided for manufacturing piezoelectric vibrating devices that do not contain any unwanted gas or water vapor inside the devices. In an exemplary method, a base wafer is prepared including multiple package bases each having a first main surface and a second main surface. The base wafer also includes a pair of through-holes disposed between adjacent package bases of the base wafer. A piezoelectric vibrating piece is placed on each package base. A lid wafer is prepared that includes multiple package lids. A sealing material is applied to the base wafer or lid wafer in peripheral bands used for bonding the bases and lids together and defines respective interior cavities. The band of sealing material includes a communicating groove that communicates from the inner cavity to the first through-hole. The base wafer and lid wafer are subject to heat and compression to effect bonding. Meanwhile, the cavities are allowed to ventilate through the communicating grooves and through-holes to ensure that the cavities have a desired vacuum level or inert gas contents before completion of sealing.