Patent ID: 8303755

Claim:
A method for manufacturing a piezoelectric device, comprising: sandwiching a piezoelectric frame wafer between a lid wafer and a base wafer having at least one wiring through-hole, wherein the piezoelectric frame wafer comprises a vibrating piece and an outer frame surrounding the vibrating piece; bonding the frame wafer, lid wafer, and base wafer together as a sandwich; cleaning a surface of a unit of eutectic metal by applying to the eutectic metal a concentration of hydrofluoric acid in water, and subsequently washing the eutectic metal in water; after cleaning, annealing the eutectic metal at a temperature that is slightly lower than or equal to the melting temperature of the eutectic metal; after annealing, arranging the unit of eutectic metal on the wiring through-hole; and melting the unit of eutectic metal in a vacuum state or inert-gas atmosphere to cause eutectic metal of the unit to enter the through-hole.