| 摘要 |
PURPOSE:To ensure desirable airtightness of a substrate without breaking ceramics by specifying a diameter of through holes and filling the through holes with Cu powder and/or Au powder. CONSTITUTION:A circuit conductor 14 is formed (into thin film patterns) by vapor deposition or by sputtering and etching while through holes are filled with Cu and/or Au. The through holes have a diameter of 0.25mm or less. The through holes with a diameter of 0.25mm or less does not break a ceramic substrate and provide desirable airtightness. Further, such through holes have sufficiently small resistance. |
