Semiconductor memory devices.

摘要

In a manufacturing method for a semiconductor memory device, wherein a capacitor having a double fin-shaped structure is provided, a storage electrode is formed by applying a thick planar material (31) which is capable of being wet-etched, between the double fins consisting of conductive layers (30,34). Accordingly, the problem of a photolithography process caused by poor step difference of a conventional fin structure can be solved. By removing the wet-etchable material (31) before pattern-etching the first conductive layer (30) the storage electrode surface is less likely to be damaged as compared to a RIE step. Further, the storage electrode may be formed by using a thin high temperature oxide film (41) whose etching rate is great. Thus, the cell's topography may be improved and damage to the storage electrode decreased.