SEMICONDUCTOR MEMORY DEVICE HAVING MULTILAYERED STORAGE NODE CONTACT PLUG AND FABRICATING METHOD THEREOF

摘要

PURPOSE: A semiconductor memory device having a multilayered storage node contact plug is provided to improve a process margin and to prevent a crack in a process for forming a storage node contact plug while using a titanium nitride layer, by making the storage node contact plug to be filled in a storage node contact hole composed of the titanium nitride layer and a polysilicon layer. CONSTITUTION: An interlayer dielectric(15) is so formed to insulate a pad(13) of a semiconductor substrate(11). A bit line stack(23) is formed on the interlayer dielectric. A bit line spacer(25) is formed on both sidewalls of the bit line stack and has the storage node contact hole(26) between the sidewalls such that the storage node contact hole exposes the surface of the pad through the interlayer dielectric. The multilayered storage node contact plug is formed in the storage node contact hole, having a structure in which the first and second storage node contact plugs(29a,31a) are sequentially formed.