Semiconductor device and method for manufacturing the same

A semiconductor device, comprising:

• a first contact plug extending in a predetermined direction and including a step converting a cross section area of the first contact plug perpendicular to the predetermined direction discontinuously via the step in one end side;
• a first structure electrically connected to the first contact plug;
• and
• a second insulating layer formed on side surface of a part of the first contact plug closer to the first structure than the step.

A method for manufacturing a semiconductor device, comprising.

• (1) preparing a semiconductor substrate including a protruding region;
• (2) forming a second insulating layer on side surface of the protruding region;
• (3) forming a first structure on top surface of the protruding region;
• (4) performing anisotropic etching to the semiconductor substrate in a position corresponding to the protruding region, from a rear side opposite to a side on which the first structure is formed, 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;
• and
• (5) forming at least a first contact plug within the second opening.

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.

A method for manufacturing a semiconductor device, comprising:

• (1) forming a first insulating layer over 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, at least one protruding region the portions of which other than a portion below the first mask pattern are exposed;
• (4) forming a second insulating layer in the exposed portions 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) performing anisotropic etching on the semiconductor substrate from the rear surface side thereof opposite to a side on which the first structure is formed, so as to leave a portion in the semiconductor substrate corresponding to the first structure, the anisotropic etching being performed so that the etching rate of the semiconductor substrate is faster than the etching rate of the second insulating layer;
• and
• (9) implanting an impurity into a portion in the semiconductor substrate corresponding to the first structure, to form a first contact plug.

A method for manufacturing a semiconductor device, comprising:

• (1) forming a second insulating layer over the entire surface of a semiconductor substrate;
• (2) forming a first impurity-diffused region in the semiconductor substrate;
• (3) performing anisotropic etching on the rear surface side of the semiconductor substrate opposite to a side on which the second insulating layer is formed, in a position of the semiconductor substrate corresponding to the first impurity-diffused region, the anisotropic etching being performed 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 first impurity-diffused region;
• and
• (4) forming at least a first contact plug within the second opening.

A method for manufacturing a semiconductor device, comprising:

• (1) forming a first insulating layer over 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, at least one protruding region the portions of which other than a portion below the first mask pattern are exposed;
• (4) forming a second insulating layer in the exposed portions 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) performing anisotropic etching on the semiconductor substrate from the rear surface side thereof opposite to a side on which the first structure is formed, the anisotropic etching being performed in a position corresponding to the protruding region within the semiconductor substrate 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 first impurity-diffused region;
• (9) forming a third insulating layer on the inner wall of the second opening;
• and
• (10) forming at least a first contact plug within the second opening.

A method for manufacturing a semiconductor device, comprising:

• (1) forming a first insulating layer over the entire surface of a silicon semiconductor substrate;
• (2) forming a first mask pattern on the first insulating layer;
• (3) etching the first insulating layer and the silicon semiconductor substrate using the first mask pattern as a mask to form, below the first mask pattern, a silicon semiconductor region projecting from a predetermined plane of the silicon semiconductor substrate;
• (4) forming a second insulating layer in the exposed portions of the silicon semiconductor substrate;
• (5) forming a first structure including the silicon semiconductor region;
• (6) polishing the silicon 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 silicon semiconductor substrate;
• (7) performing anisotropic etching on a position corresponding to the silicon semiconductor region within the silicon semiconductor substrate from the rear surface side thereof, so that the etching rate of the silicon 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 silicon semiconductor region;
• (8) forming a third insulating layer on the inner wall of the second opening;
• and
• (9) forming at least a first contact plug within the second opening.