A semiconductor device and a method of fabricating a semiconductor device, the semiconductor device including a semiconductor substrate including a first region and a second region; an interlayer insulating layer on the semiconductor substrate, the interlayer insulating layer including a first opening on the first region and having a first width; and a second opening on the second region and having a second width, the second width being greater than the first width; at least one first metal pattern filling the first opening; a second metal pattern in the second opening; and a filling pattern on the second metal pattern in the second opening, wherein the at least one first metal pattern and the second metal pattern each include a same first metal material, and the filling pattern is formed of a non-metal material.