Reduction of the anomalous VT behavior in MOSFETs with high-κ/metal gate stacks

Abstract:

This study investigates the impact of different nitridation processes on hafnium silicon oxynitride (HfSiON) dielectrics. It is demonstrated that the threshold voltage (V<inf>T</inf> vs. L<inf>g</inf>) behavior at short gate lengths is strongly impacted by the nitridation process, depending on the Hf/(Hf+Si) ratio and the HfSiON thickness. A Plasma nitridation in oxidizing ambient results in a modification of the dielectric that can explain the anomalous V<inf>T</inf> behavior in devices integrated with hafnium-based dielectrics and metal gate. Reduction in anomalous V<inf>T</inf> behavior and limited gate leakage is achieved by applying a thermal nitridation in a NH<inf>3</inf> ambient on Hf-rich silicon oxynitride. © 2007 Elsevier B.V. All rights reserved.

Año de publicación:

2007

Keywords:

• Hafnium silicon oxynitride
• Nitridation
• Threshold voltage

Fuente:

scopus