Patent ID: 7388157

Claim:
A printed wiring board comprising: a first substrate including a core layer made of resin containing carbon fibers; a second substrate superimposed on a surface of the first substrate, said second substrate including a core layer containing carbon fibers, said second substrate having an outline different from an outline of the first substrate so that a stepped surface is formed on the first substrate; and an electrically-conductive pad exposed on the stepped surface, wherein the core layer of the second substrate comprises: a first resin layer made of a resin material containing carbon fibers, said first resin layer defining a through hole at a predetermined position; an insulating layer overlaid on a surface of the first resin layer, said insulating layer made of a resin material containing glass fibers; and a second resin layer overlaid on a surface of the insulating layer, said second resin layer made of a resin material containing carbon fibers, said second resin layer defining a through hole at a position aligned with the through hole defined in the first resin layer.