| 摘要 |
PROBLEM TO BE SOLVED: To provide a wiring board having a highly reliable wiring conductor formed on the basis of samples to show the fact that even though the thick wiring conductor exposed on the surface of an insulating board is provided, cracks in the insulating board, disconnections of other wiring conductors due to the development of the cracks and the like will not be generated, it is not generated that wiring conductor is separated from space parts for wiring in the insulating board and grooves formed in the insulating board and the other wiring conductor is disconnected, reduction in the resistance of the wiring conductor is realized, and the wiring conductor adapts to an increase in a current without impairing its heat conductivity. SOLUTION: This wiring board is provided with a 100-μm or larger thickness wiring conductor 5, formed by laminating a 10 to 100-μm thick and high-melting point metal layer 2 containing an inorganic component at a ratio of 5 to 40 volume parts to a high-melting point metal 100 volume parts, a 50 to 600-μm thick porous metal layer 3 of 3 to 25% for void volume rate and a 50 to 600-μm thick and low-resistance wiring layer 4 in this order on the surface of a ceramic insulating board 1 containing alumina, aluminium nitride, silicon nitride or the like as its main components from the side of the board 1 and at least SiO2 is contained in the layer 2 as the inorganic component in the layer 2, and moreover a ceramic component in the board 1 is contained in the layer 2 as the inorganic component in the layer 2. |
