Method for forming dual high-k metal gate using photoresist mask and structures thereof

US7915115B2 · kind B2 · utility

Assignees

• International Business Machines Corporation · US
• Advanced Micro Devices, Inc. · US

Inventors

• Michael P. Chudzik · Beacon, US
• Rashmi Jha · Wyoming, US
• Naim Moumen · Walden, US
• Keith Kwong Hon Wong · Wappingers Falls, US
• Ying H. Tsang · Katy, US

Key dates

• Filing date: Jun 3, 2008
• Grant date: Mar 29, 2011
• Expiry date: Jan 6, 2029

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/31138
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Methods for forming a front-end-of-the-line (FEOL) dual high-k gate using a photoresist mask and structures thereof are disclosed. One embodiment of the disclosed method includes depositing a high-k dielectric film on a substrate of a FEOL CMOS structure followed by depositing a photoresist thereon; patterning the high-k dielectric according to the photoresist; and removing the photoresist thereafter. The removing of the photoresist includes using an organic solvent followed by removal of any residual photoresist including organic and/or carbon film. The removal of residual photoresist may include a degas process, alternatively known as a bake process. Alternatively, a nitrogen-hydrogen forming gas (i.e., a mixture of nitrogen and hydrogen) (N2/H2) or ammonia (NH3) may be used to remove the photoresist mask. With the use of the plasma nitrogen-hydrogen forming gas (N2/H2) or a plasma ammonia (NH3), no apparent organic residual is observed.