Wiring substrate with buried substrate having linear conductors

A wiring substrate comprising:

• a core layer including a resin substrate and a through-hole penetrating through the resin substrate in a thickness direction;
• a buried substrate including a plate-like body and a plurality of linear conductors penetrating the plate-like body in the thickness direction, the buried substrate being disposed within the through-hole of the core layer;
• a first insulating layer covering a first surface of the resin substrate;
• a first pad pattern formed on a first surface of the buried substrate;
• and
• a third wiring pattern formed on the first surface of the resin substrate and covered by the first insulating layer,
• wherein
• in the plurality of linear conductors, a gap between the adjacent linear conductors is smaller than a diameter of each of the linear conductors,
• a thickness of the third wiring pattern is greater than a thickness of the first pad pattern,
• the first insulating layer comprises a first layer covering the first surface of the resin substrate and an outer peripheral portion of the first surface of the buried substrate, and exposing the first pad pattern and an inner portion of the first surface of the buried substrate, the inner portion of the first surface of the buried substrate being disposed within the outer peripheral portion of the first surface of the buried substrate, and a second layer covering the first pad pattern and extending on the first layer,
• the wiring substrate further comprises:
• a fifth wiring pattern formed on the second layer, the fifth wiring pattern connected to the first pad pattern and connected to the third wiring pattern, and
• the first layer is disposed in a space between an inner wall surface of the through-hole and a side wall of the buried substrate, and covers side surfaces of the buried substrate.