Patent ID: 7029937

Claim:
A method of manufacturing a semiconductor device comprising: (a) forming a depression from a first surface of a semiconductor substrate in which an integrated circuit is formed, the semiconductor substrate having an electrode on the first surface, the electrode having an insulating film formed thereon; (b) providing an insulating layer on the bottom surface and an inner wall surface of the depression; (c) providing a conductive portion inside the insulating layer; (d) etching a second surface of the semiconductor substrate opposite to the first surface, with a first etchant having characteristics such that the etching amount with respect to the semiconductor substrate is greater than the etching amount with respect to the insulating layer, to cause the conductive portion to project while covered by the insulating layer; (e) etching at least a portion of the insulating layer formed on the bottom surface of the depression with a second etchant having characteristics such that at least the insulating layer is etched without forming a residue on the conductive portion, to expose the conductive portion, (a) including etching the insulating film to expose the electrode, etching the exposed surface of the electrode to form a depressed area, forming a hole in the depressed area of the electrode to expose the first surface, and then forming the depression from the first surface of the semiconductor substrate, in (c), the conductive portion being formed on the depressed area of the electrode.