| 摘要 |
<p>PURPOSE:To obtain a thick-film resistor layer by forming a circuit conductor layer by a direct electroless copper plating method after roughening the surface of a ceramic insulating substrate and forming the thick-film resistor layer on the main surface of the insulating substrate and thick-film conductor layers which become external connecting terminals at both end sections of the resistor layer. CONSTITUTION:After through holes 6 are formed at prsescribed locations of a ceramic insulating substrate 5, the substrate 5 is subjected to an etching process in a high- temperature alkaline solution so as to finely roughen the surface of the alumina. Then thick-film conductor layers 8 for external connecting terminals are formed on one main surface of the substrate 5 by applying conductor paste prepared by mixing silver, glass flit, and resin binder together to the surface and calcining the paste in the air. After forming the layer 8, a thick-film resistance layer 7 is formed by applying ruthenium oxide-based glaze paste having a prescribed resistance value to the layer 8 and calcining the paste in the air. After an insulating protective film 9 and activating layer 10 are formed, a circuit conductor layer 12 of metallic copper is formed on the entire surface of the ceramic insulating substrate 5 including the through holes 6 by dipping the substrate in a electroless copper plating liquid.</p> |
