CAPACITOR FORMING METHOD OF SEMICONDUCTOR MEMORY DEVICE

摘要

A fabrication method of a storage electrode is provided to enhance the surface area of the storage electrode of cylindrical capacitor. The method comprises the steps of: sequentially forming doped oxide layers(4)(6)(8) and undoped oxide layers(5)(7)(9) on a silicon substrate having a first polysilicon layer(3); selective etching the oxide layers using etchant having a selectivity in order to form an hole having convex and concave; forming a second polysilicon conductive layer(10) in the hole; forming a first spacer by slope etching the oxide layers; forming a third polysilicon layer and etching the third polysilicon layer to form a second spacer(11); and removing the oxide layers. Thereby, it is possible to increase the surface area of the storage electrode by forming a pillar having convex and concave at the center of the capacitor.