Patent ID: 7709328

Claim:
A method for fabricating a semiconductor device, the method comprising: forming a device isolation structure in a semiconductor substrate having a pad insulating film to define an active region; etching a predetermined region of the device isolation structure by using a recess mask to form a recess exposing sidewalls of the semiconductor substrate under the active region; etching a portion of the semiconductor substrate under the recess and the active region to form an under-cut space separating an upper semiconductor substrate from a lower semiconductor substrate under the active region, wherein a bridge type channel structure is formed at the upper semiconductor substrate; removing the pad insulating film to expose the semiconductor substrate including the bridge type channel structure; forming a gate insulating film over the exposed semiconductor substrate including the bridge type channel structure; and forming a coaxial type gate electrode over the gate insulating film of a gate region to fill the recess and the under-cut space, wherein the coaxial type gate electrode surrounds the bridge type channel structure.