| 摘要 |
PURPOSE:To enhance the reliability of the surface packaging of chip parts and reduce the warpage at reflow soldering process by a structure wherein an aramid fiber woven cloth or aramid fiber non-woven cloth prepreg layer impregnated with specified content of epoxy resin is interposed between a prepreg layer and a copper foil. CONSTITUTION:An epoxy resin-impregnated glass woven cloth or glass non- woven cloth prepreg layer 2, on one side of which a copper foil 1 is placed, is formed under heat and pressure. At this time, epoxy resin-impregnated aramid fiber woven cloth or aramid fiber non-woven cloth prepreg layer 3 is interposed between the prepreg layer 2 and the copper foil 1. The epoxy resin content of the aramid fiber woven cloth or aramid fiber non-woven cloth prepreg is set to be less than or equal to 70 wt.%. As the epoxy resin-impregnated glass woven cloth or glass non-woven cloth prepreg consisting of said layer 2, bisphenol type epoxy resin-dicyandiamide curing type is empolyed. As the matrix impregnated with resin, glass woven cloth or glass non-woven cloth is employed. As the copper foil, electrolytic copper with a thickness of 18 mum is used without adhesive. Further, the preferable thickness of the layer 3 after curing is more than or equal to 3 % of the total thickness of a copper-clad laminated sheet. |
