Semiconductor memory device having multi-layered storage node contact plug and method for fabricating the same

摘要

A semiconductor memory device includes a bit line stack and a storage node contact hole which are aligned at bit line spacers formed at both side walls of the bit line stack and exposes a pad. The semiconductor memory device includes a multi-layered storage node contact plug in which a first storage node contact plug and a second storage node contact plug are sequentially formed. The first storage node contact plug is formed of titanium nitride and the second storage node contact plug is formed of polysilicon. An ohmic layer may be formed on the pad and under the first storage node contact plug. A barrier metal layer, which acts as a third storage node contact plug, may be formed on the second storage node contact plug.