Abstract: A wiring board includes a core layer having a first through hole formed therein, a magnetic resin filled inside the first through hole, a second through hole formed in the magnetic resin, and a plating film covering an inner wall surface of the second through hole. The plating film includes an electroless plating film, and an electrolytic plating film. The electroless plating film makes direct contact with an inner wall surface of the second through hole.

Abstract: A wiring substrate includes a first insulation layer, a first wiring layer including a pad formed on an upper surface of the first insulation layer, a second insulation layer formed on the upper surface of the first insulation layer to cover the first wiring layer, a first hole extending through the second insulation layer in a thickness-wise direction and partially exposing an upper surface of the pad, a second hole formed in the second insulation layer to be continuous with the first hole and widening a bottom opening of the first hole and entirely exposing a side surface of the pad in a thickness-wise direction, a via wiring filling the first hole and the second hole, and a second wiring layer formed on an upper surface of the second insulation layer integrally with the via wiring. The second hole partially exposes the upper surface of the first insulation layer.

Abstract: A wiring substrate includes a first wiring layer, an insulation layer covering the first wiring layer, a first through hole extending through the insulation layer and exposing part of the upper surface of the first wiring layer, and a second through hole arranged adjacent to the first through hole. The second through hole extends through the insulation layer in the thickness-wise direction and exposes part of the upper surface of the first wiring layer. A bottom portion of the first through hole is in communication with a bottom portion of the second through hole through a communication hole. A via wiring fills the first through hole, the second through hole, and the communication hole. A second wiring layer is formed integrally with the via wiring on the insulation layer.

Abstract: A wiring board includes a core layer having a first through hole formed therein, a magnetic resin filled inside the first through hole, a second through hole formed in the magnetic resin, and a plating film covering an inner wall surface of the second through hole. The plating film includes an electroless plating film, and an electrolytic plating film. The electroless plating film makes direct contact with an inner wall surface of the second through hole.

Abstract: A wiring substrate includes: a base material; a first through-hole and a second through-hole that are formed in the base material; magnetic material that is filled in the first through-hole; a third through-hole that is formed in the magnetic material; a first plating film that covers an inner wall surface of the third through-hole; and a second plating film that covers an inner wall surface of the second through-hole and the first plating film. The first plating film includes a first electroless plating film that is in contact with the inner wall surface of the third through-hole, and a first electrolytic plating film that is laminated on the first electroless plating film.

Abstract: A wiring board includes a core layer having a first through hole formed therein, a magnetic resin filled inside the first through hole, a second through hole formed in the magnetic resin, and a plating film covering an inner wall surface of the second through hole. The plating film includes an electroless plating film, and an electrolytic plating film. The electroless plating film makes direct contact with an inner wall surface of the second through hole.

Abstract: A wiring substrate includes: a base material; a first through-hole and a second through-hole that are formed in the base material; magnetic material that is filled in the first through-hole; a third through-hole that is formed in the magnetic material; a first plating film that covers an inner wall surface of the third through-hole; and a second plating film that covers an inner wall surface of the second through-hole and the first plating film. The first plating film includes a first electroless plating film that is in contact with the inner wall surface of the third through-hole, and a first electrolytic plating film that is laminated on the first electroless plating film.

Abstract: A wiring board includes a core layer having a first through hole formed therein, a magnetic resin filled inside the first through hole, a second through hole formed in the magnetic resin, and a plating film covering an inner wall surface of the second through hole. The plating film includes an electroless plating film, and an electrolytic plating film. The electroless plating film makes direct contact with an inner wall surface of the second through hole.