Electrical characteristics of MOS capacitors with HfTiON as gate dielectric

Abstract

HfTiN film was deposited by co-reactive sputtering and then was annealed in different gas ambients at temperature of 650 °C for 2 min to form HfTiON film. Capacitance-voltage and gate-leakage characteristics were investigated. The N2O-annealed sample exhibited small interface-state and oxide-charge densities, and enhanced reliability, which was attributed to the fact that nitridation could create strong SiN bonds to passivate dangling Si bonds and replaced strained Si-O bonds, thus forming a hardened dielectric/Si interface with high reliability. As a result, it is possible to prepare high-quality HfTiON gate dielectric of small-scaling CMOS devices in the industry-preferred N2O environment. © 2009 Wuhan University of Technology and Springer-Verlag GmbH.