| 摘要 |
PURPOSE:To obtain an airtight case for an electron tube which is minimally heated and has high adhesive strength at low cost by directly fusing a copper member to the end surface of a cylindrical ceramic member and then joining the thus formed body and a metallic member together through the copper member. CONSTITUTION:After a copper member 2 is brought into contact with the end surface of a cylindrical ceramic member 1, heating is performed at a temperature not lower than the eutectic point for the combination of copper and oxygen and not higher than the melting point of copper for 10-30min to firmly fuse the copper member 2 to the cylindrical ceramic member 1. When a nonoxidized ceramic such as AlN or SiC is used for the cylindrical member 1, it is desirable that the surface of the member 1 be subjected to oxidation or similar treatment. The above heating is performed in an atmosphere of an inactive gas such as nitrogen gas either when the copper member 2 contains oxygen or when the surface of the copper member 2 is oxidized. It is performed in an oxidative atmosphere containing a slight amount of oxygen when the copper member 2 does not contain oxygen. Next, after a brazing material 4 is interposed between the copper member 2 and the end surface of a metallic member, these members are joined together by high frequency brazing. |
