Method for producing deep vertical structures in silicon substrates

US5658472A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Johann W. Bartha · Aidlingen, DE
• Johann Greschner · Neckartenzlingen, DE
• Robert Junginger · Jülich, DE
• Georg Kraus · Konz, DE

Key dates

• Filing date: Jun 7, 1995
• Grant date: Aug 19, 1997
• Expiry date: Jun 7, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/3081
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method is provided for producing deep substantially vertical structures in silicon substrates, wherein in a first step, the silicon substrate is anisotropically plasma etched to a first predetermined depth, thereby creating a first structure. Subsequently, the surface of the substrate is covered conformally with an etch-resistant coating, and the horizontal parts of said coating are selectively removed. Following this removal, the substrate is anisotropically plasma etched at low temperatures to a second predetermined depth with a mixture of SF.sub.6 /O.sub.2, whereby a second structure is created. Finally, the vertical parts of the coating are removed.