Piezoelectric device and method for manufacturing thereof
View Patent ↗A piezoelectric device, includes: a package; a piezoelectric resonator element housed in the package; a lid made of metal and bonded to the package by seam welding to seal the package air-tightly; a metal film for frequency adjustment that is provided to the piezoelectric resonator element; and a window part provided to the lid and enabling a light to transmit therethrough.
1. A method for manufacturing a piezoelectric device, the piezoelectric device being formed by bonding a piezoelectric resonator element to an inside of a package and sealing by a lid made of metal, comprising:
a) forming the package, the piezoelectric resonator element, and the lid individually;
b) bonding to mount the piezoelectric resonator element in the inside of the package;
c) sealing the package by the lid air-tightly; and
d) irradiating with a laser light from an outside via a window part that is made of glass and provided to the lid so as to transpire a part of a metal film for frequency adjustment, the metal film being provided to the piezoelectric resonator element, wherein
in the step c), a metal brazing material is disposed between a metal part, the metal part being formed on a bonding surface of the package, and the lid, and the metal brazing material is molten with an electric current applied from a side of the lid so as to bond the package and the lid.
2. A method for manufacturing a piezoelectric device, the piezoelectric device being formed by bonding a piezoelectric resonator element to an inside of a package and sealing by a lid made of metal, comprising:
a) forming the package, the piezoelectric resonator element, and the lid individually;
b) bonding to mount the piezoelectric resonator element to the inside of the package;
c) sealing the package by the lid air-tightly; and
d) degassing under heat through a through-hole that is a sealing hole provided to a bottom part of the package, and melting and filling a metal material in the sealing hole so as to seal the hole, after the step c), wherein
in the step c), a metal brazing material is disposed between a metal part, the metal part being formed on a bonding surface of the package, and the lid, and the metal brazing material is molten with an electric current applied from a side of the lid so as to bond the package and the lid.
3. The method for manufacturing a piezoelectric device according to claim 2 , wherein a metal roller that is an electrode for seam welding is brought into contact with an end part of the lid, the part being close to the window part of the lid, to start the welding, and rolled to progress the welding in a manner that the roller moves close to the window part and then apart from the window part, in the step c).