High area capacitor formation using dry etching

US5153813A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Gottlieb S. Oehrlein · Clarksville, US
• Gary W. Rubloff · Clarksville, US

Key dates

• Filing date: Oct 31, 1991
• Grant date: Oct 6, 1992
• Expiry date: Oct 31, 2011

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D1/714

Abstract

The invention provides a method of increasing the capacitance of a capacitor which comprises forming a capacitor having a main vertical trench and one or more lateral trenches extending off the main vertical trench. The capacitor has alternating first and second silicon regions, for example n-doped and p-doped silicon regions. After a main vertical trench is dry etched through the first and second silicon regions, the etch characteristics of the alternating first and second silicon regions are utilized to selectively dry etch lateral trenches, thereby increasing the surface area of the capacitor and the capacitance of the capacitor. Capacitors produced by this method are also provided.