| 摘要 |
PURPOSE:To produce a circuit board suitably employed in hybrid integrated circuit device and the like by significantly enhancing adhesion between a wiring conductor composed at least of one kind of tungsten or molybdenum and a circuit conductor of copper as well as electrical conduction therebetween. CONSTITUTION:A metal layer 3 composed at least of one kind of nickel or cobalt containing 0.1-3.0wt.% of boron is applied on the surface of an insulating board 1 provided with a wiring conductor 2 composed at least of one kind of tungsten or molybdenum and then the metal layer 3 is fired in reducing atmosphere at 600-1100 deg.C. At least one kind of tungsten or molybdenum in the wiring conductor 2 is then diffused into the metal layer 3 to produce an intermetallic layer 4 mainly composed of an alloy of at least one kind of nickel or cobalt, at least one kind of tungsten or molybdenum, and boron. Thereafter, a circuit conductor 5 of copper is applied on the surface of the insulating board 1 including the intermetallic layer 4. |
