Wet cleans for cobalt disilicide processing

US6335294B1 · kind B1 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• David Paul Agnello · Wappingers Falls, US
• Mary Conroy Bushey · South Burlington, US
• Donna K. Johnson · Underhill, US
• Jerome B. Lasky · South Burlington, US
• Peter J. Lindgren · South Burlington, US
• Kirk D. Peterson · Jericho, US

Key dates

• Filing date: Apr 22, 1999
• Grant date: Jan 1, 2002
• Expiry date: Apr 22, 2019

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/32134
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method for removing a formation of oxide of titanium that is generated as a byproduct of a process that forms cobalt disilicide within an insulated-gate field effect transistor (FET). The method applies a chemical reagent to the FET at a predetermined temperature, and for a predetermined period of time, necessary for removing the formation, wherein the reagent does not chemically react with the cobalt disilicide. A reagent that accomplishes this task comprises water (H2O), ammonium hydroxide (NH4OH), and hydrogen peroxide (H2O2), wherein the NH4OH and the H2O2 each comprise approximately 4% of the total reagent volume. An effective temperature is 65° C. combined with a 3 minute period of application.