| 摘要 |
PROBLEM TO BE SOLVED: To provide a circuit board wherein a plurality of layered circuit patterns can be interconnected wholesomely without using any through-hole connection method and the circuit board comprising a plurality of layers can be formed inexpensively making wiring patterns with a high disposal density realizable. SOLUTION: In a circuit board with a wiring pattern 2a stuck closely on one surface of an insulation board 1, providing in the insulation board 1 a connection hole 3 reaching the wiring pattern 2a, a conductive bump 4 made to grow by plating from the wiring pattern 2a is buried in the connection hole 3 to serve as a connection means with a wiring pattern 6a stuck closely on the other surface of the insulation board 1. |
