Method for fabricating semiconductor device capable of covering facet on plug

摘要

The present invention relates to a method for fabricating a semiconductor device capable of improving an overlap margin that occurs when forming a conductive pattern, such as a bit line or a bit line contact. In order to achieve this effect, the method for fabricating a semiconductor device includes the steps of: forming a plug passing through an insulation layer to be contacted with a substrate board; forming a planarization insulation layer on an entire surface including the plug so as to cover defects appeared at a surface of the plug; forming a protective insulation layer on the planarization insulation layer for preventing losses of the planarization insulation layer resulted from a subsequent cleaning process; performing a process with an etchant; and forming a conductive layer contacted to the plug by passing through the protective insulation layer and the planarization insulation layer.