Patent ID: 7339224

Claim:
A trench capacitor for use in a semiconductor memory cell, comprising: a trench, which is formed in a substrate; a region, provided in the substrate, as first capacitor electrode; a dielectric layer on the trench wall as capacitor dielectric; and a region, provided in the trench, made of a metallic filling material as second capacitor electrode, wherein the region made of the conductive metallic filling material fills the lower region of the trench, above the region made of the conductive metallic filling material, a region made of a dielectric filling material with a cavity for taking up mechanical stresses fills an upper region of the trench; and the region made of the metallic filling material is connected via a conductive contact layer on the trench walls, which is applied above the dielectric layer, to an electrical contact provided above the region made of the dielectric filling material in the trench for the electrical connection of the trench capacitor.