| 摘要 |
PROBLEM TO BE SOLVED: To provide a prepreg which improves reliability in the interlayer connection established by non-through via holes. SOLUTION: The prepreg is provided in an insulating layer being superposed and cured on the surface of an inner layer circuit board. A resin is impregnated into a glass cloth having a thickness of less than 60μm, in which not more than 10% of the entire cloth is free of warp and weft. Thus, the distribution of thread in the entire glass cloth, which is incorporated in the insulating layer, is substantially unified. As a result, portions where holes can be hardly made due to overstiffness or portions where excessively large holes are made due to oversoftness, are hardly present in the insulating layer, thereby stably realizing even size non-through via holes. COPYRIGHT: (C)2004,JPO |
