| 摘要 |
PROBLEM TO BE SOLVED: To form more fine and accurate wiring layer by forming an easily roughing insulation resin layer to be easily roughed on an upper surface of heat resistant resin difficult to be roughed, thereby obtaining a sufficient adhesive strength between the wiring layer formed on the resin layer and the easily roughing insulation resin layer. SOLUTION: Coating layers 2 made of easily roughing epoxy insulation resin are formed on both upper and lower surfaces of an insulating board 1 made of BT(bismaleimide-triazine) resin-glass composite material. A wiring layer 9 made of a thin film layer 7 and an electrolytic copper plating layer 8 is formed on each of the layer 2 and an inner wall surface of a through hole, and has a continuity with one another via a wiring layer (conductor 10 in the through hole) in the hole. Thus, even in the case of using an insulation board made of resin difficult to be roughed like the BT resin, a fine wiring layer can be formed from its first layer, and an anchoring effect for raising adhesive properties of the wiring layer with the easily roughed resin layer is easily obtained. |
