To enhance reliability by locally bringing a specified ratio of activated metal contained into contact with a ceramic container before temperature rising, and airtightly sealing a lid body to the ceramic container with a brazing material containing the specified ratio of activated metal.
The ratio X of activated metal in a brazing material, coming into contact with a ceramic container before temperature rising is specified to 0<X<1, preferably to 0≤X≤0.05, and the content (y) [g/m2] of the activated metal is specified to 10-X≤y≤10X+2. Thereby, oxidation before brazing of the activated metal such as Ti, Zr, Hf, Nb, Ta and Cr is prevented, and sealing by reduction of the ceramic is not obstructed. Drop in joining capability caused by forming, during cooling, of an intermetallic compound of the activated metal not contributing to joining and Ni in the cover body is also prevented. As the brazing material, an alloy containing Ti and Ag or Cu of the main component, or a clad material integrally having Ag-Cu on both sides of Ti is preferable, and addition of at least one of In, Sn, Mn, Zn, and Cd is preferable.
KUSANO TAKASHI
SEKI KEISEI
YAMAMOTO ATSUSHI
TOSHIBA CORP