Components having different heights are installed in a multilayer substrate using a metal core layer formed by bonding a plurality of metal layers. The metal core layer includes through-holes and a spot-faced portion. Passive components and an active component are disposed in the through-holes and the spot-faced portion, respectively. These components are connected to conductive patterns formed on wiring layers, with connecting vias therebetween. Contact faces of each component with the connecting vias are controlled so as to be disposed at the same level with the metal layers.