US 6,310,375 B1 · Trench capacitor with isolation collar and corresponding manufacturing method

Abstract

The present invention provides a trench capacitor, particularly for use in a semiconductor memory cell (100), having an isolation collar (168) with a trench (108) formed in a substrate (101); said isolation collar (168) formed in the upper region of said trench (108); an optional buried plate (165) in said substrate region surrounding said lower region of said trench (180) as a first capacitor plate; a dielectric layer (164) for lining said lower region of said trench (108) and said isolation collar (168) as capacitor dielectric; and a conductive second fill material (161) filled in said trench (108) as a second capacitor plate; wherein said diameter of said lower region of said trench (108) is at least equal to said diameter of said upper region of said trench (108). Moreover, the invention provides a corresponding manufacturing method.

Claims6

Dependent claims

A trench capacitor comprising:

a trench formed in a substrate, the trench comprising an upper and a lower region, wherein a diameter in the lower region is at least equal to about a diameter in the upper region;
an isolation collar comprising oxide in an upper region of the trench;
a dielectric layer lining the collar in the upper region of the trench and a lower region of the trench, the dielectric layer serving as a node dielectric of the trench capacitor;
and
a conductive material filling the trench, the conductive material serving as a plate of the capacitor;
and
a transistor coupled to the capacitor via a strap located above the isolation collar, the strap contacts the first plate of the capacitor, wherein the transistor and capacitor forms a memory cell.

4 more elements

Dependencies are inferred from the claim text.

Trench capacitor with isolation collar and corresponding manufacturing method

Life of this patent

Trench capacitor with isolation collar and corresponding manufacturing method

Life of this patent

Abstract

Claims6