Work function adjustment in high-K metal gate electrode structures by selectively removing a barrier layer

US8440559B2 · kind B2 · utility

Assignee

• GlobalFoundries Inc. · KY

Inventors

• Markus Lenski · Dresden, DE
• Klaus Hempel · Dresden, DE
• Vivien Schroeder · Radeberg, DE
• Robert Binder · Dresden, DE
• Joachim Metzger · Rockenberg, DE

Key dates

• Filing date: Sep 21, 2012
• Grant date: May 14, 2013
• Expiry date: Sep 21, 2032

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/691
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Generally, the present disclosure is directed work function adjustment in high-k metal gate electrode structures. In one illustrative embodiment, a method is disclosed that includes removing a placeholder material of a first gate electrode structure and a second gate electrode structure, and forming a first work function adjusting material layer in the first and second gate electrode structures, wherein the first work function adjusting material layer includes a tantalum nitride layer. The method further includes removing a portion of the first work function adjusting material layer from the second gate electrode structure by using the tantalum nitride layer as an etch stop layer, removing the tantalum nitride layer by performing a wet chemical etch process, and forming a second work function adjusting material layer in the second gate electrode structure and above a non-removed portion of the first work function adjusting material layer in the first gate electrode structure.