Semiconductor device and method of manufacturing the same

摘要

A semiconductor device includes a word line structure that extends in a first direction on an active region defined on a substrate. First and second contact pads are formed on the active region at both sides of the word line structure. Bit line structures are electrically connected to the first contact pad and extend in a second direction substantially perpendicular to the first direction. An insulation layer structure is formed on the substrate having the bit line structures. A storage node contact plug is electrically connected to the second contact pad through the insulation layer structure. A storage node electrode, which may be part of a capacitor, is formed on the storage node contact plug. The storage node contact plug has a lower portion and an upper portion having a width wider than that of the lower portion, with vertical sides perpendicular to the first and second directions.