According to embodiments of the invention, a bit line interlayer insulating layer is placed over a semiconductor substrate. A plurality of parallel bit line patterns are placed on the bit line interlayer insulating layer. Each of the bit line patterns has a bit line and a bit line capping layer pattern stacked thereon. Bit line spacers covers side walls of the bit line patterns, buried holes penetrate predetermined regions of the bit line interlayer insulating layer between the bit line patterns. And a plurality of storage node contact plugs are placed between the bit line patterns surrounding by the bit line spacers. At this time, the storage node contact plugs fill the buried holes.