MANUFACTURE OF CERAMIC PRINTED WIRING BOARD

PURPOSE: To prevent the occurrence of a skip phenomenon which occurs at the time of performing electroless plating by heat-treating a ceramic printed wiring board after a thick resistor layer, terminal layer, and insulator layer are formed on the board and before an electroless-plated layer is formed. CONSTITUTION: After a thick resistor layer 2, terminal layer 3, and insulator layer 4 are formed on the surface of a ceramic board 1, the board 1 is heat- treated at 150 deg. or higher temperature for more than 3 hours. Consequently, the exposed section 3r of the layer 3 is reduced and the activity of the section 3r against the electroless plating to be performed in the succeeding process is improved. When the heat-treating temperature exceeds 400 deg.C, the layer 4 is apt to remelt and the glass components in the layers 4 and 3 cause a chemical reaction. As a result, the glass layer in the layer 3 is taken into the layer 4 and the possibility of occurring such a bleed out phenomenon that the layer 3 becomes porous and a disconnection fault occurs becomes higher. Thereafter, an electroless-plated layer 6 and electroplated layer 8 are formed on the board 1.