Patent ID: 6337463
Filing Date: 2002-01-08
Classification: B23K,H05K

Abstract:
A method of forming a penetration hole for a through hole in a thermosetting resin copper-clad laminate having at least two copper layers, in which copper foils of the thermosetting resin copper-clad laminate are processed with an energy of 20 to 60 mJ/pulse sufficient for removing the copper foils by means of the pulse oscillation of a carbon dioxide gas laser, the method comprising forming or disposing a coating or a sheet of a substrate containing an organic substance and 3 to 97% by volume of at least one powder selected from the group consisting of a metal compound powder which has a melting point of at least 900Â° C. and a bond energy of at least 300 KJ/mol, a carbon powder and metal powder on at least a copper foil surface to be irradiated with the carbon dioxide gas laser, and irradiating a surface thereof with necessary pulses of the carbon dioxide gas laser to form the penetration hole.