| 摘要 |
PURPOSE:To reduce a thermal effect except on the part that needs it by a method wherein dye is mixed into an insulating layer on a conductive layer to absorb laser rays. CONSTITUTION:A lower conductive layer 201 is formed on a polymer insulating layer 200 through a conventional method such as a screen printing method and a polymer insulating material mixed with dye such as a chelate compound is filled thereon and set to form a polymer insulating layer 202. Next, laser rays 203 are irradiated onto the part where a viahole is bored to sublimate the part of the polymer insulating layer 202 to obtain the viahole 204. As the polymer insulating layer 202 is mixed with dye, the laser rays sublimate only the part of the layer 202 irradiated by them. Thereafter, the laser rays 203 continue to be irradiated, but as the irradiation is performed with the laser rays short in pulses, a lower conductor layer 201 increases a little in temperature. But these process, the viahole 104 can be formed in a high density without wastage, so that density enhancement can be realized. |
