Semiconductor memory device with capacitor formation method, for e.g. DRAM

摘要

The method is for the formation of a semiconductor memory device with capacitor, in which is provided one substrate, and one transfer transistor formed on the substrate. A storage capacitor is coupled to a drain and source region of the transfer transistor. The method initially involves forming an insulator, overlaying the transfer transistor. An etching passivation layer is then formed on the insulator before forming a second insulator, a stack layer with a pinhole is then formed on tha latter insulator. A third insulator is then formed on the stack sidewall, followed by a fourth insulator which it approximately fills the pinhole. The latter two insulators are then removed to form an opening without contacting with the etching passivation layer, and a conductive layer is then made to fill the pinhole and the opening. The stack layer is subsequently removed and a fifth insulator and second conductive layer are formed. A vertical conductive connection is then formed via etching to connect the two conducting layers to the drain region of transfer transistor. The second conductive layer is then partially removed to form one storage electrode of the storage capacitor. This is then followed by the removal of the fifth insulator and the exposure of the surface of both conductive layer layers to form a single dielectric layer. An opposed storage is then formed on the dielectric surface.