| 摘要 |
PROBLEM TO BE SOLVED: To enable a semiconductor plastic package to be improved in adhesion to a surface metal foil, enhanced in heat dissipating properties, and restrained from absorbing moisture through the underside of a chip, by a method wherein at least a viahole is joined to an inner metal plate through a rear surface, and truncated conical metal projections provided to the metal plate are connected to the rear side of a metal foil which fixes a semiconductor chip. SOLUTION: A viahole is bored in a board so as to reach to an inner metal board, the board is subjected to a de-smearing treatment and plated with metal, and a circuit is formed on each side of the board. A semiconductor chip is fixed on the upper surface of a metal-cored printed wiring board provided with through-holes C, truncated conical metal projections are provided to a metal board b possessed of an iron core at positions where the semiconductor chip is fixed through a well-known etching method. Thermally conductive adhesive agent, is attached to the inner metal truncated conical metal projections of the printed wiring board under a metal foil d where the semiconductor chip is amounted if necessary, and the printed wiring board is bonded to the metal foil d. By this setup, a semiconductor plastic package enhanced in adhesion to a surface metal foil and reliability can be obtained. |
