WIRING BOARD AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To provide a ceramic wiring board where a wiring circuit layer can be turned to a fine wiring, lessened in resistance, enhanced in adhesion to an insulating board, and improved in yield and a method of manufacturing the same. SOLUTION: A wiring circuit layer 3 formed of high-purity metal conductor such as metal foil which is above 99 wt.% in metal content and formed of at least one element selected out of Cu, Ag, Al, Au, Ni, Pt, and Pd is formed on the surface of a ceramic insulating board as buried so as to be flush with the insulating board 2, the wiring circuit layer 3 is formed like an inverted trapezoid in cross section in the direction vertical to the direction of wiring, an angleαformed by the base and side of the above trapezoid is 45 to 80 deg., the average roughness of the surface of the wiring circuit layer 3a which is buried in the insulating board 2 is set at 200 nm or above, and the average thermal expansion coefficient of the insulating board 2 is set at 6 ppm/ deg.C or above at temperatures of 40 to 400 deg.C.