Tunable Work-Function Engineering of TiC-TiN Compound by Atomic Layer Deposition for Metal Gate Applications

Abstract

In this paper, we present the impact of the atomic layer deposition of carbon-containing TiN films (TiC-TiN) on the effective work function of metal-oxide-semiconductor devices. By adjusting the deposition temperature of TiC-TiN, the carbon content, which is dependent on the deposition mode, could be altered. Hence, the work function of TiC-TiN as a metal gate material could be tuned. The results revealed that the bonding concentration of Ti-C increases at higher deposition temperatures, whereas the work function of the TiC-TiN metal gate decreases from 5.0 to 4.6 eV. A high work function (5.0 eV) metal gate is suitable for a p-field effect transistor (FET) application and the midgap work function (4.6 eV) is suitable for a fully depleted silicon-on-insulator FET. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3459932] All rights reserved.