Patent ID: 7566969

Claim:
A semiconductor device, comprising: a wiring substrate having a main surface, a back surface opposing to the main surface, a plurality of terminals formed on the main surface, a plurality of lands formed on the back surface, at least one through hole formed between the main surface and the back surface, an insulating film formed over the main surface and the back surface, and a conductive material arranged in the through hole, the conductive material being electrically connected with the land and the terminal; a semiconductor chip mounted on the main surface of the wiring substrate; a conductive member electrically connecting a pad of the semiconductor chip with one of the terminals of the wiring substrate; and an external terminal formed on each of the lands of the back surface of the wiring substrate; wherein the through hole has a first opening opened on the main surface of the wiring substrate, and a second opening opened on the back surface of the wiring substrate; wherein a size of the first opening of the through hole is larger than that of the second opening of the through hole; wherein the first opening is occluded by a part of the insulating film; wherein the second opening is occluded by the conductive material; and wherein the through hole is formed in a area overlapping with the land and the external terminal in a plane view.