JP2907122B

In a process for forming a storage node electrode in the COB structure DRAM, after a titanium nitride film is formed on a surface of a second interlayer insulator film, a node contact hole is formed to penetrate through the titanium nitride film and the underlying interlayer insulator films, and then, an N+ polysilicon film is formed to cover the titanium nitride film and to fill the node contact hole. This N+ polysilicon film is patterned by an anisotropic dry etching to form a silicon film pattern. An exposed titanium nitride film which is not covered by the silicon film pattern is converted into a titanium oxide. Thus, a storage node electrode is formed of the silicon film pattern and the titanium nitride film remaining under the silicon film pattern, with no notch being formed in the storage node electrode.