Method of producing active semiconductor layers of different thicknesses in an SOI wafer

US7001804B2 · kind B2 · utility

Assignee

• ATMEL Germany GmbH · DE

Inventors

• Franz Dietz · Heilbronn, DE
• Volker Dudek · Ditzingen, DE
• Michael Graf · Leutenbach, DE

Key dates

• Filing date: Jan 31, 2005
• Grant date: Feb 21, 2006
• Expiry date: Jan 31, 2025

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D86/01
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

An SOI wafer including an active semiconductor material layer on an insulating layer is processed to form thereon first and second active semiconductor regions that respectively have different thicknesses and that are vertically and laterally insulated. In the process, a trench is etched into the SOI wafer, seed openings are formed in the bottom of the trench to reach the underlying active material layer, the trench is filled with epitaxially grown semiconductor material progressing from the seed openings, some of the epitaxially grown material is removed to form the second active regions, and oxide layers are provided so that the second active regions are laterally and vertically insulated from the first active regions formed by remaining portions of the active semiconductor material layer.