Semiconductor integrated circuit device effectively decreased in surface state regardless of non-permeable layer for chemical species against surface state and process for fabricating thereof

Abstract

A cell plate electrode is shared between storage capacitors of memory cells incorporated in a semiconductor dynamic random access memory device of the type having the storage capacitors over bit lines, and slits are formed in the cell plate electrode in such a manner that the boundaries between channel regions and gate oxide layers are horizontally spaced from the outer periphery of the cell plate electrode and the slits by distances equal to or less than a critical distance determined on the basis of a diffusion length of hydrogen in an inter-level insulating layer, thereby causing the hydrogen to surely reach the boundaries for reducing the density of surface state.