Wiring Substrate and Semiconductor Device

A wiring substrate comprising:

• a core including a first surface and a second surface located at a side opposite to the first surface, wherein the core includes a plurality of electronic component accommodating bores that extend through the core in a thickness direction between the first surface and the second surface;
• a first wiring layer formed on the first surface of the core, wherein the first wiring layer includes a first opening;
• a second wiring layer formed on the second surface of the core, wherein the second wiring layer includes a second opening;
• a plurality of electronic components, each arranged in one of the electronic component accommodating bores;
• an insulating material covering the first surface and the second surface of the core, wherein the electronic component accommodating bores are filled with the insulating material;
• a first wiring structure formed on a first surface side of the core;
• and
• a second wiring structure formed on a second surface side of the core;
• wherein the electronic component accommodating bores extend through the core at portions exposed from the first opening of the first wiring layer and the second opening of the second wiring layer, and
• the core further includes a partition located between adjacent ones of the electronic component accommodating bores, the partition being formed by part of the core, wherein the partition includes
• a first surface exposed in the first opening of the first wiring layer, and
• a second surface exposed in the second opening of the second wiring layer.