Semiconductor device and a bit line and the whole of a bit line contact plug having a vertically uniform profile

Abstract

A semiconductor device comprises: a semiconductor substrate including a cell region and a peripheral region; an insulating film formed on the top portion of the semiconductor substrate of the cell region; a bit line contact hole including the etched insulating film to expose the semiconductor substrate; a bit line contact plug buried in the bit line contact plug; and a bit line formed on the top portion of the bit line contact plug to have the same width as that of the bit line contact plug. The thickness of the insulating film around a cell bit line is minimized so as to vertically form a profile of the cell bit line, thereby improving an overlay margin of a storage node contact and an active region.