| 摘要 |
<p>PROBLEM TO BE SOLVED: To propose a manufacturing method of a circuit board for a multilayer printed wiring board wherein viaholes having a uniform quality can be effectively formed without causing thermal damage to a resin adhesive agent layer and a PET film. SOLUTION: In this manufacturing method of a circuit board, a copper foil 12 is stuck on one surface of a rigid insulating base substance 10, and not-penetrating holes 18 which reach the copper foil 12 from the other surface of the insulating base substance 10 are formed by using irradiation with a CO2 gas laser. Irradiation of an ultraviolet ray laser or an excimer laser is performed to the inside of the not- penetrating holes 18, and resin residue left in the not-penetrating holes are dismeared. After that, the insides of the not-penetrating holes which are dismeared are filled with conductive paste 20. A copper foil 24 is subjected to thermo-compression bonding, covering the conductive paste 20 exposed from the other surface of the insulating base substance 10, and filled viaholes 22 electrically connecting the conductive paste 20 and the copper foil 24 are formed. After that, the copper foils 12, 24 stuck on both surfaces of the insulating base substance 10 are treated by etching, and conductor circuit patterns 26, 28 are formed.</p> |
