Patent ID: 8669478

Claim:
A wiring substrate, comprising: a first insulating layer constituting a surface of the wiring substrate, and exhibiting a black color or a gray color; a first connection pad formed to be exposed from the surface of the wiring substrate, and buried in the first insulating layer, and the first connection pad having a side face and back face covered with the first insulating layer; a second insulating layer constituting a reverse surface of the wiring substrate, and exhibiting a black color or a gray color; a second connection pad formed to be exposed from the reverse surface of the wiring substrate, and buried in the second insulating layer, and the second connection pad having a side face and back face covered with the second insulating layer; and a connection hole formed in the second insulating layer, and exposing the face of the second connection pad, located to the reverse surface side of the wiring substrate, wherein the connection hole has a side wall surface formed like a curved surface, and has a shape in which an area of the opening portion which is opened to the outer surface of the second insulating layer is formed larger than an area of the bottom surface of the connection hole.