Patent ID: 7990026

Claim:
A surface-mount type crystal unit comprising: a container body comprising a bottom wall layer of an approximately rectangular shape and a frame wall layer having an opening at a center thereof and provided on the bottom wall layer, said container body having a recess formed by the opening of the frame wall layer and having a planar projection shape of an approximate rectangle; a sealing metal film formed on an upper surface of the frame wall layer surrounding the recess; a metal cover bonded to the sealing metal film by a eutectic alloy; a pair of crystal holding terminals that are formed at a location to be on an upper surface of the bottom wall layer while on an inner bottom surface of the recess, said location being on one end portion side of the container body; a crystal blank that is received in the recess by electrically connecting to the pair of crystal holding terminals and is hermetically encapsulated in the recess by the metal cover; a pair of external terminals for crystal that are provided to two corners of four corners of an outer bottom surface of the container body and are electrically connected to the crystal connecting terminals, respectively; and a grounding external terminal that is formed at a corner of the outer bottom surface on the other end portion side of the container body, wherein a first conduction metal film is formed at the corner of a position corresponding to the grounding external terminal on a stack surface of the frame wall layer with the bottom wall layer, wherein the first conduction metal film is electrically connected to the sealing metal film through an end face metal film formed on an inner side surface of the frame wall layer at the corner of the position corresponding to the grounding external terminal, wherein a second conduction metal film is formed at the corner of the position corresponding to the grounding external terminal on a stack surface of the bottom wall layer with the frame wall layer, wherein the second conduction metal film is electrically connected to the grounding external terminal through an end face metal film formed on an outer side surface of the container body, and wherein the bottom wall layer and the frame wall layer are stacked, so that the first conduction metal film and the second conduction metal film are bonded to each other.