Patent attributes
Disclosed herein is a method for forming a gate structure in a semiconductor device. The method comprises forming a SiGe film on a predetermined region of a silicon substrate corresponding to a bit-line node portion where a bit-line junction is formed, growing a silicon film over the silicon substrate having the SiGe film formed thereon, selectively etching the SiGe film, embedding a dielectric material into a portion where the SiGe film is removed, forming a stepped profile on the silicon film by etching a predetermined portion of the silicon film such that the bit-line node portion is included in the stepped profile, and forming a gate on the silicon film having the stepped profile formed therein such that the gate overlaps the stepped profile. The dielectric pad prevents the bit-line junction from spreading downward upon operation of the gate, thereby enhancing a punch-through phenomenon.
