US 5,858,853 AGranted

Method for forming capacitor electrode having jagged surface

AssigneeNEC Corporation

InventorsSeiichi Shishiguchi, Tatsuya Suzuki, Hideo Kawano, Keiji Shiotani, Masao Mikami

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Abstract

In a method for forming a capacitor, after preparing a substrate having at least one device area thereon, an amorphous silicon film containing one type of dopant is formed on the device area. A mask layer comprising mask islands is formed and distributed on a surface of the amorphous silicon film. The surface of the amorphous silicon is dry-etched by using the mask layer as a selective etching mask to produce a jagged surface having a lot of protrusions. After forming the jagged surface, the amorphous silicon film is changed into a polycrystalline silicon film serving as a storage electrode. Finally, a dielectric film and then another storage electrode are formed sequentially on the jagged surface of the storage electrode.

Claims40

Dependent claims

A method of forming a capacitor comprising a dielectric film intervening between a first electrode and a second electrode, said method comprising the steps of:

a) preparing a substrate having at least one device area thereon;
b) forming an amorphous silicon film on said device area, said amorphous silicon film containing one type of dopant;
c) forming a mask layer comprising mask islands distributed on a surface of said amorphous silicon film;
d) dry-etching said surface of said amorphous silicon using said mask layer as a selective etching mask into a jagged surface having protrusions;
e) changing said amorphous silicon film with said jagged surface thereon into a polycrystalline silicon film serving as said first electrode;
f) depositing said dielectric film on said jagged surface of said first electrode;
and
g) forming said second electrode on said dielectric film.

5 more elements

Dependencies are inferred from the claim text.