BORING METHOD OF COPPER CLAD PLATE WHICH USES CO2 GAS LASER

摘要

PROBLEM TO BE SOLVED: To form penetrating holes for through-holes and/or holes for via holes which are superior in connection reliability with a surface layer copper foil, on a copper clad plate containing at least aluminum hydroxide, using high output power CO2 gas laser. SOLUTION: An auxiliary layer (a) for boring is formed on a copper foil surface of a copper clad plate, which has thermosetting resin composition containing at least aluminum hydroxide in an insulating layer. After that, by using CO2 gas energy sufficient for removing a copper foil b, the auxiliary layer (a) is irradiated directly with a CO2 gas laser through pulse oscillation of the CO2 gas laser, and penetrating holes d for through-holes and/or holes (2) for via holes are formed. Thereby holes, where copper foil connecting property of a surface layer copper foil with the insides of the holes is extremely satisfactory, and superior in reliability can be obtained.