Wiring substrate

A wiring substrate, comprising:

• a first wiring layer;
• a first insulating layer covering an upper surface and a side surface of the first wiring layer;
• a first through hole extending through the first insulating layer in a thickness-wise direction and exposing part of the upper surface of the first wiring layer;
• a first via wiring having a landless structure and filling the first through hole;
• a first recess formed in an upper surface of the first via wiring and recessed downward from an upper surface of the first insulating layer;
• a second insulating layer formed on the upper surface of the first insulating layer and filling the first recess;
• a second recess formed in an upper surface of the second insulating layer and overlapping the first recess in plan view;
• a second through hole extending from the second recess to the first recess;
• a second via wiring filling the second through hole;
• a second wiring layer formed on a wall surface of the second recess and formed integrally with the second via wiring;
• and
• a third wiring layer formed on the upper surface of the second insulating layer, wherein
• the second via wiring has a planar size that is smaller than that of the first via wiring, and
• the second wiring layer has an upper surface located downward from an upper surface of the third wiring layer.