Patent ID: 9406868
Filing Date: 2016-08-02
CPC Classification: B01D,C23C,H01L,H03H,Y10T

Claim Text:
1. A manufacturing method for a piezoelectric resonator device, wherein the piezoelectric resonator comprises a piezoelectric resonator plate where an excitation electrode is formed, and an upper lid member and a lower lid member that hermetically seals the excitation electrode, the piezoelectric resonator plate having a joining region where the upper lid member is joined and a joining region where the lower lid member is joined on front and back main surfaces, the upper lid member having a region on one main surface where the piezoelectric resonator plate is joined, the lower lid member having a region on one main surface where the piezoelectric resonator plate is joined, wherein the piezoelectric resonator plate and the region of the upper lid member are joined to each other via a joining material, and the piezoelectric resonator plate and the region of the lower lid member are joined to each other via a joining material, the manufacturing method comprising: a metal film formation step of laminating a metal film constituted by at least two types of metals on at least one of a substrate of the joining region of the piezoelectric resonator plate, a substrate of the region of the upper lid member, and a substrate of the region of the lower lid member; a diffusion step of promoting metal diffusion inside the metal film by heat processing after the metal film formation step; and an etching step of roughening a surface of the substrate of the at least one of the piezoelectric resonator plate, the upper lid member, and the lower lid member, by performing wet etching with an etchant caused to penetrate into the metal film obtained after the diffusion step and thereby forming a large number of micropores in the surface of the substrate of the at least one of the piezoelectric resonator plate, the upper lid member, and the lower lid member.