Semiconductor device and method of fabricating the same

Provided are a semiconductor device and a method of fabricating the semiconductor memory device. A contact plug is formed by wet etching. An aspect ratio of SAC is decreased and SAC fail is reduced so that a process margin is secured. The semiconductor device includes a semiconductor substrate comprising an active region and a device isolation layer defining the active region, a conductive pattern formed on the semiconductor substrate, and a nitride layer formed on the semiconductor substrate perpendicularly to the conductive pattern.