Method of fabricating a semiconductor component with active regions separated by isolation trenches

US7078324B2 · kind B2 · utility

Assignee

• ATMEL Germany GmbH · DE

Inventors

• Volker Dudek · Ditzingen, DE
• Michael Graf · Leutenbach, DE

Key dates

• Filing date: Sep 20, 2004
• Grant date: Jul 18, 2006
• Expiry date: Sep 20, 2024

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76232
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

To form a semiconductor component having active regions separated from one another by trenches as isolation structures, a method involves forming a shallow trench in a semiconductor body, thereafter forming a deep trench within the shallow trench in the semiconductor body, and thereafter completely driving dopant atoms into the semiconductor body to form a well region doped with the dopant. The dopant may be previously introduced by implantation into a surface layer, and then the dopant is finally completely driven into the well region by thermally supported diffusion after forming the deep trench. The shallow and deep trenches together form a compound trench with stepped side walls. Two oppositely doped wells may be formed on opposite sides of the compound trench, which thus isolates the two wells from one another. Active regions may be formed in the two wells.