Patent ID: 7799591

Claim:
A method for manufacturing a semiconductor device, comprising: (1) forming a first insulating layer across the entire surface of a semiconductor substrate; (2) forming a first mask pattern on the first insulating layer; (3) etching the first insulating layer and the semiconductor substrate using the first mask pattern as a mask to form, below the first mask pattern, a protruding region a portion of which other than a portion below the first mask pattern is exposed; (4) forming a second insulating layer in the exposed portion of the semiconductor substrate; (5) removing the first mask pattern; (6) forming an interlayer insulating film over the entire surface of the semiconductor substrate; (7) forming a first opening within the interlayer insulating film in a position thereof corresponding to the protruding region, removing the first insulating layer on the protruding region, and further forming a first structure on the protruding region; (8) forming a protective substrate on the first structure; (9) polishing the semiconductor substrate from the rear surface side thereof opposite to a side on which the first structure is formed to reduce a thickness of the semiconductor substrate; (10) performing anisotropic etching to the semiconductor substrate in a position corresponding to the protruding region, from the rear surface side thereof, so that the etching rate of the semiconductor substrate is faster than the etching rate of the second insulating layer, to form a second opening until the second opening reaches at least the protruding region; (11) forming a third insulating layer on the inner wall of the second opening; and (12) forming at least a first contact plug within the second opening.