US 5,847,424 AGranted

Capacitor of semiconductor memory device and manufacturing method thereof

AssigneeSamsung Electronics Co., Ltd.

InventorHo-kyu Kang

Life of this patent

Estimating the term…

Loading patent…

Abstract

A capacitor structure of a DRAM device and a method thereof, including a first electrode formed in each unit memory cell to be connected to a source of a transistor, a deteriorating prevention film formed at the lowermost surface of the first electrode, exclusive of a portion where the first electrode is connected to the source of a transistor, an underlayer formed beneath the deterioration prevention film, an undercut formed between the underlayer and deterioration prevention film, a high-dielectric film formed on surfaces of the first electrode, underlayer and deterioration prevention film which is exposed by the undercut, a reaction/diffusion prevention film formed on the high-dielectric film, formed on the first electrode and underlayer, exclusive of an area around the undercut, and a second electrode formed on the entire surface of the high-dielectric film and reaction/diffusion prevention film, thereby preventing increase of leakage current amount caused by the undercut formed during the capacitor manufacturing process.

Claims5

Dependent claims

A capacitor for a unit memory cell of a semiconductor memory device, comprising:

a substrate having a transistor formed thereon, said transistor including a source/drain;
an insulator formed on said substrate and said transistor;
a contact hole formed in said insulator to expose the source of said transistor;
a first electrode formed on said insulator and connected to the source of said transistor through said contact hole;
a deterioration prevention film formed on a lower surface of said first electrode and a top surface of said insulator, wherein said deterioration prevention film has a first lower surface portion contacting said top surface of said insulator and a second lower surface portion spaced apart from said top surface of said insulator by an undercut located below said lower surface of the first electrode;
a high permittivity dielectric film formed on surfaces of said first electrode, insulator and deterioration prevention film;
a barrier metal film formed on the high permittivity film on said first electrode;
and
a second electrode formed on the entire surface of the barrier metal film.

6 more elements

Dependencies are inferred from the claim text.