Trench capacitor and method for fabricating the same

US6781180B1 · kind B1 · utility

Assignee

• Infineon Technologies AG · DE

Inventors

• Schrems Martin · Gleisdorf, AT
• Dirk Drescher · Radeberg, DE
• Helmut Wurzer · Dresden, DE
• Wolfram Karcher · Osterburken, DE

Key dates

• Filing date: Oct 2, 2000
• Grant date: Aug 24, 2004
• Expiry date: Nov 20, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B12/0387

Abstract

A trench capacitor for use in a semiconductor memory cell is formed in a substrate and includes a trench having an upper region and a lower region. An insulation collar is formed in the upper region of the trench. The lower region of the trench extends through a buried well. A dielectric layer, which is formed from tungsten oxide, serves as a capacitor dielectric. A conductive trench filling, which is filled into the trench, is formed from silicon or a tungsten-containing material such as tungsten, tungsten silicide or tungsten nitride.