Self-aligned buried strap process using doped HDP oxide

US6667504B1 · kind B1 · utility

Assignees

• International Business Machines Corporation · US
• Infineon Technologies North America Corp. · US

Inventors

• Jochen Beintner · Wappingers Falls, US
• Wolfgang Bergner · Waldbüttelbrunn, DE
• Richard A. Conti · Altamont, US
• Andreas Knorr · Saratoga Springs, US
• Rolf Weis · Dresden, DE

Key dates

• Filing date: Mar 24, 2003
• Grant date: Dec 23, 2003
• Expiry date: Mar 24, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B12/0383

Abstract

The invention provides a trench storage structure that includes a substrate having a trench, a capacitor conductor in the lower part of the trench, a conductive node strap in the trench adjacent the capacitor conductor, a trench top oxide above the capacitor conductor, and a conductive buried strap in the substrate adjacent the trench top oxide. The trench top oxide includes a doped trench top oxide layer above the conductive strap, and an undoped trench top oxide layer above the doped trench top oxide layer.