SONOS memory cells and arrays and method of forming the same

US7323388B2 · kind B2 · utility

Assignees

• Infineon Technologies AG · DE
• Infineon Technologies Flash GmbH & Co. KG · DE

Inventors

• Joachim Deppe · Dresden, DE
• Christoph Ludwig · Radeberg, DE
• Christoph Kleint · Dresden, DE
• Josef Willer · Riemerling, DE

Key dates

• Filing date: Mar 4, 2005
• Grant date: Jan 29, 2008
• Expiry date: Jan 5, 2026

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/037

Abstract

A trench (2) is fabricated in a silicon body (1). The walls (4) of the trench are provided with a nitrogen implantation (6). An oxide layer between the source/drain regions (5) and a word line applied on the top side grows to a greater thickness than a lower oxide layer of an ONO storage layer fabricated as gate dielectric at the trench wall. Instead of the nitrogen implantation into the trench walls, it is possible to fabricate a metal silicide layer on the top sides of the source/drain regions in order to accelerate the oxide growth there.