Wiring substrate

A wiring substrate, comprising:

• a wiring substrate having a cavity;
• and
• a plurality of wiring structures accommodated in the cavity of the wiring substrate and comprising at least two of a first wiring structure, a second wiring structure and a third wiring structure such that the wiring structures include a plurality of relay lines internally incorporated and having a plurality of connection points exposed on upper surfaces of the wiring structures at end portions of the relay lines,
• wherein the first wiring structure includes a silicon layer in a lower part of the first wiring structure, the second wiring structure includes a glass layer in a lower part of the second wiring structure, the third wiring structure includes a resin layer and does not include a glass layer or a silicon layer in a lower part of the third wiring structure, and the at least two of the first, second and third wiring structures differ in at least one of planar size and minimum L/S of the relay lines.