An interposer includes a substrate made of an inorganic material; a
through wiring including conductors embedded in through holes; and an
upper wiring and (or)a lower wiring. The through wiring, the upper wiring
and the lower wiring are respectively formed on preliminary wiring
patterns that are additionally simultaneously or sequentially formed on
layers made of an insulating material applied to at least wiring forming
parts of the substrate, and are formed with a metal mold itself used for
forming the preliminary wiring patterns or layers made of a wiring
material applied by a printing operation, a plating operation or a
deposition on the preliminary wiring patterns formed on the layers of the
insulating material by transferring a fine structure pattern of the metal
mold.