MULTILAYER WIRING BOARD AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a multilayer wiring board in which a heat dissipation property from a semiconductor element is enhanced, on which the semiconductor element having a large calorific value can be mounted, and whose reliability is high, and to provide a semiconductor device. SOLUTION: In the multilayer wiring board 10, a wiring layer 26 is laminated and formed on a core substrate 12 composed of a metal. A thermal via 16 which is connected from the core substrate 12 in a pillar shape and which thermally connects a heat sink 40 to the core substrate 12 is installed in an inner layer, in a part to which the heat sink 40 bonded and attached to the outer face of the substrate is bonded. In addition, a thermal via 18 which thermally connects the core substrate 12 to the semiconductor element 30 is installed.