Method for fabricating trenches having hallows along the trenches side wall for storage capacitors of DRAM semiconductor memories

US6387773B1 · kind B1 · utility

Assignee

• Infineon Technologies AG · DE

Inventor

• Manfred Engelhardt · Feldkirchen-Westerham, DE

Key dates

• Filing date: Jun 30, 2000
• Grant date: May 14, 2002
• Expiry date: Jun 30, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B12/0387

Abstract

A method for fabricating trenches for storage capacitors of DRAM semiconductor memories by plasma etching semiconductor substrates, includes fabricating a partial trench region with a cross-sectional profile deviating from essentially constant toward a larger cross-sectional profile. A surface of the partial trench region is passivated and the etching/passivating step is continued periodically, in order to fabricate further partial trench regions, until a predetermined overall trench depth has been reached.