PASSIVE DEVICE BUILT-IN SUBSTRATE, ITS FABRICATION METHOD, AND MATERIAL FOR BUILDING PASSIVE DEVICE BUILT-IN SUBSTRATE

PROBLEM TO BE SOLVED: To provide a passive device built-in substrate, as well as its fabrication method, that has passive devices built-in such as a capacitor, resistance, etc., and whose structure and manufacturing steps are simplified. SOLUTION: The passive device built-in substrate has multiple resin films 23 including thermoplastic resin, conductor patterns 22 laminated alternately with these multiple resin films 23, and electrically conductible compositions 51 that electrically connect the conductor patterns 22 embedded in via holes 24 formed in each resin film 23 and set on both sides of each resin film 23. A pair of conductor patterns 22a and 22b are arranged on both sides of the resin film 23 at opposite positions with only the resin film 23 between, thus building a passive device functioning as a capacitor 30 in a multilayer substrate. Accordingly, there is no need to use any special materials and others for building the capacitor 30, and its structure is very streamlined. COPYRIGHT: (C)2004,JPO