Patent ID: 7876572

Claim:
A wiring board, comprising: a first surface including a semiconductor-chip mount area on which a semiconductor-chip is to be mounted; and a second surface, opposite to the first surface, to which an external connection terminal is to be provided; and a dummy wiring pattern comprising a plurality of dummy wiring lines located in the semiconductor-chip mount area, wherein a width of the dummy wiring lines is approximately constant along their length, wherein the width of the dummy wiring lines is approximately equal to a width of free spaces between the dummy wiring lines, wherein the dummy wiring lines are arranged such that at least one free space between adjacent dummy wiring lines extends from a location adjacent an edge of the semiconductor chip mount area to a central portion of the semiconductor chip mount area, wherein the dummy wiring lines of the dummy wiring pattern are arranged in four quadrants, wherein within each quadrant, all the dummy wiring lines extend parallel to one another, and wherein the dummy wiring lines in each quadrant extend in a direction that is perpendicular to the dummy wiring lines in both adjacent quadrants.