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

US8298894B2 · 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: May 21, 2010
• Grant date: Oct 30, 2012
• Expiry date: Feb 23, 2031

Classification

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

Abstract

In a replacement gate approach in sophisticated semiconductor devices, a tantalum nitride etch stop material may be efficiently removed on the basis of a wet chemical etch recipe using ammonium hydroxide. Consequently, a further work function adjusting material may be formed with superior uniformity, while the efficiency of the subsequent adjusting of the work function may also be increased. Thus, superior uniformity, i.e., less pronounced transistor variability, may be accomplished on the basis of a replacement gate approach in which the work function of the gate electrodes of P-channel transistors and N-channel transistors is adjusted after completing the basic transistor configuration.