Single sided buried strap

US6573137B1 · kind B1 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Ramachandra Divakaruni · Ossining, US
• Jack A. Mandelman · Stormville, US
• Wolfgang Bergner · Waldbüttelbrunn, DE
• Gary B. Bronner · Stormville, US
• Ulrike Gruening · Wappingers Falls, US
• Stephan Kudelka · Radeberg, DE
• Alexander Michaelis · Wappingers Falls, US
• Larry Nesbit · Farmington, US
• Carl Radens · Lagrangeville, US
• Till Schloesser · Dresden, DE
• Helmut Tews · Poughkeepsie, US

Key dates

• Filing date: Jun 23, 2000
• Grant date: Jun 3, 2003
• Expiry date: Mar 3, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B12/0383

Abstract

A method for clearing an isolation collar from a first interior surface of a deep trench at a location above a storage capacitor while leaving the isolation collar at other surfaces of the deep trench. A barrier material is deposited above a node conductor of the storage capacitor. A layer of silicon is deposited over the barrier material. Dopant ions are implanted at an angle into the layer of deposited silicon within the deep trench, thereby leaving the deposited silicon unimplanted along one side of the deep trench. The unimplanted silicon is etched. The isolation collar is removed in locations previously covered by the unimplanted silicon, leaving the isolation collar in locations covered by the implanted silicon.