| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain a method of forming a blind via hole and/or a through hole that have less pore size variation and excellent hole reliability by directly emitting carbon dioxide laser onto a copper-clad laminate which is stuck with a thin copper foil having a thickness of 2μm or below. <P>SOLUTION: As a copper foil for the copper-clad laminate having at least two copper layers, a copper foil having a thickness of 3-5μm with a carrier metallic foil attached is used. After the lamination is formed, the carrier metallic foil is peeled off, the copper foil on the surface and the rear of the copper-clad plate is etched in the thickness direction to 2μm or below, desirably 0.5-1.5μm. As a result, the copper-clad laminate excellent in the tolerance of copper foil thickness is obtained. The laminate is then irradiated, directly from the above, with one energy selected from 3-19 mJ carbon dioxide laser energies; thus, the blind via hole and/or the through hole is formed. <P>COPYRIGHT: (C)2004,JPO</p> |
