Methods for inhibiting outgrowth of silicide in self-aligned silicide process

US5196360A · kind A · utility

Assignee

• Micron Technologies, Inc. · US

Inventors

• Trung T. Doan · Los Gatos, US
• Gurtej S. Sandhu · Boise, US

Key dates

• Filing date: Apr 6, 1992
• Grant date: Mar 23, 1993
• Expiry date: Apr 6, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S148/019

Abstract

The present invention is directed to methods for preparing silicide contact areas on integrated circuit devices which inhibit outgrowth of silicide and formation of potential short circuit paths between adjacent silicide contact areas. This may be achieved by depositing a nitrogen-rich titanium nitride layer over the conventional titanium layer prior to silicidation. In those regions on the integrated circuit device where titanium is deposited on spacer oxide regions separating adjacent silicide contact areas, excess nitrogen from the nitrogen-rich titanium nitride layer reacts with the titanium film to form titanium nitride. The final structure after silicidation contains titanium silicide contact areas separated by titanium nitride regions. The titanium nitride regions inhibit outgrowth of titanium silicide from the silicide contact areas. After silicidation, excess titanium nitride and titanium may be removed by etching.