SEMICONDUCTOR DEVICE AND METHOD FOR FABRICATING THE SAME

Provided are a semiconductor device and a manufacturing method thereof. The semiconductor device includes: an insulating film having a trench exposing a part of a semiconductor substrate; a buffer pattern which has a lattice constant different from the semiconductor substrate, disposed in the trench, and comprises: a bottom part having a first width where crystalline defects are trapped, and a plurality of pin parts having a second width smaller than the first width, and extended from the bottom part; a gate electrode crossing the pin parts of the buffer pattern; and a gate insulating film interposed between the pin parts and the gate electrode.