Trench capacitor with insulation collar and corresponding fabrication method

US6423607B1 · kind B1 · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Lars Heineck · Dresden, DE
• Tobias Jacobs · Mannheim, DE

Key dates

• Filing date: Sep 23, 1999
• Grant date: Jul 23, 2002
• Expiry date: Sep 23, 2019

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B12/038

Abstract

The trench capacitor, which is particularly suited for use in a semiconductor memory cell, is formed in a trench in a substrate. A region in the substrate defines a first capacitor plate. An insulation collar is formed in the upper region of the trench. A dielectric layer on the trench wall forms a capacitor dielectric. A conductive filling material fills the trench and forms a second capacitor plate. The dielectric layer at least partly surrounds the insulation collar. The invention furthermore provides a corresponding fabrication method.