| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a multilayer board excellent in heat resistance and surface smoothness. SOLUTION: An adhesive epoxy resin 2 is applied by 50-90μm to one side of a metal foil 1 and a metal foil 1 is applied, on the adhesive resin 2, to the surface of a circuit board 4 formed with an inner layer circuit 3. It is then hot pressed under heating conditions for lowering the minimum melt viscosity of the adhesive resin 2 to 6000 poise or below thus integrating the metal foil 1 on the surface of the circuit board 4 through an interlayer insulating layer 5 of the adhesive resin 2. Since fluidity of the adhesive resin 2 is improved at the time of hot press, gap between the inner layer circuit 3 can be filled completely with the interlayer insulating layer 5 of the adhesive resin 2. Furthermore, since a sufficiently thick interlayer insulating layer 5 can be formed of the adhesive resin of 50-90μm thick, level difference from an inner layer circuit can be filled with the interlayer insulating layer 5. |
