Deposition of low fluorine tungsten by sequential CVD process

US9613818B2 · kind B2 · utility

Assignee

• Lam Research Corporation · US

Inventors

• Xiaolan Ba · Fremont, US
• Raashina Humayun · Los Altos, US
• Michal Danek · Cupertino, US
• Lawrence Schloss · Palo Alto, US

Key dates

• Filing date: May 27, 2015
• Grant date: Apr 4, 2017
• Expiry date: May 27, 2035

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76877
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Provided herein are methods of depositing bulk tungsten by sequential CVD pulses, such as by alternately pulsing tungsten hexafluoride and hydrogen gas in cycles of temporally separated pulses. Some methods include depositing a tungsten nucleation layer at low pressure followed by deposition of bulk tungsten by sequential CVD to form low stress tungsten films with low fluorine content. Methods described herein may also be performed in combination with non-sequential CVD deposition and fluorine-free tungsten deposition techniques.