Patent ID: 8101482

Claim:
A method of fabricating a semiconductor device, comprising: forming a first gate trench in a first active region of a semiconductor substrate; forming a first gate layer partially filling the first gate trench; forming a spacer insulating layer on the entire surface of the semiconductor substrate having the first gate layer; and etching the spacer insulating layer to form a first spacer on an upper sidewall of the first gate trench and expose at least a portion of a top surface of the first gate layer in the first gate trench; and after etching the spacer insulating layer, first implanting ions in the first gate layer and in the first active region on both sides of the first gate layer such that (1) the first gate layer becomes a first gate electrode of a first conductivity type and (2) first impurity regions of the first conductivity type are formed on both sides of the first gate electrode.