Patent ID: 7674677

Claim:
A method for manufacturing a semiconductor device, the method comprising: performing source/drain ion implantation on a semiconductor substrate having an active region including a gate forming area to form a source area and a drain area; forming a recess in the gate forming area of the semiconductor substrate; forming a gate insulation layer over the semiconductor substrate including the recess; forming a first gate conductive layer over the gate insulation layer to fill in the recess; etching the first gate conductive layer to remove a portion of the first gate conductive layer formed at an upper end portion of the side wall of the recess that is in contact with the source area; forming an insulation layer at the upper end portion of the side wall of the recess from which the first gate conductive layer is removed; forming a second gate conductive layer over the insulation layer and the first gate conductive layer; forming a third gate conductive layer and a hard mask layer over the second gate conductive layer; and etching the hard mask layer, the third gate conductive layer, the second gate conductive layer, the first gate conductive layer, the insulation layer, and the gate insulation layer to form a gate.