SEMICONDUCTOR MEMORY DEVICE WITH STORAGE NODE OF CONCAVE TYPE AND FABRICATING METHOD THEREOF TO REDUCE DANGER OF BRIDGE AND LEANING AND EXTEND HEIGHT OF STORAGE NODE

摘要

PURPOSE: A semiconductor memory device with a storage node of a concave type is provided to reduce the danger of a bridge and leaning and extend the height of a storage node by making a storage node of a concave type have a sidewall part that becomes narrower as it goes to its upper part and has a cross section shape symmetrical with respect to its center. CONSTITUTION: A semiconductor substrate(100) is prepared. An interlayer dielectric(110) is formed on the semiconductor substrate, including a plurality of contact plugs. A plurality of storage nodes are formed on the interlayer dielectric to come in contact with each contact plug. The storage node has a bottom part directly contacting the contact plug and a sidewall part extending from both ends of the bottom part to a direction vertical to the surface of the interlayer dielectric. The width of the sidewall part becomes narrower as it goes to its upper part. The sidewall part is bilaterally symmetrical with respect to the center line in the sidewall part such that the center line vertically bisects the sidewall part with respect to the surface of the substrate.