Bottle-shaped trench capacitor with epi buried layer

US6018174A · kind A · utility

Assignees

• Siemens Aktiengesellschaft · DE
• International Business Machines Corporation · US

Inventors

• Martin Schrems · Langenbruck, DE
• Jack A. Mandelman · Stormville, US
• Joachim Hoepfner · Planegg, DE
• Herbert Schaefer · Herdorf, DE
• Reinhard Stengl · Stadtbergen, DE

Key dates

• Filing date: Jun 26, 1998
• Grant date: Jan 25, 2000
• Expiry date: Jun 26, 2018

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D1/665

Abstract

A bottle-shaped trench capacitor having an expanded lower trench portion with an epi layer therein. The epi layer serves as the buried plate of the trench capacitor. A diffusion region surrounds the expanded lower trench portion to enhance the dopant concentration of the epi layer. The diffusion region is formed by, for example, gas phase doping, plasma doping, or plasma immersion ion implantation.