High quality CVD TaN gate electrode for sub-100 nm MOS devices

Abstract

In this paper, for the first time, we present a detailed evaluation of physical and electrical properties of CVD TaN as a potential gate electrode material for sub-100 nm MOS device applications. Our results show that CVD TaN films deposited using TBTDET (tertbutylimidoirisdiethylamido tantalum) exhibit excellent thermal stability with underlying ultra thin SiO/sub 2/ up to 1000/spl deg/C and extremely stable work function (5eV@800-1000/spl deg/C) suitable for p-MOS device applications. Compared to PVD TaN, MOS devices with CVD TaN gate electrode show desirable work function for p-MOS devices, excellent stability of gate oxide thickness, leakage current, and interface properties during high-temperature annealing, and superior gate dielectric TDDB reliability. These results suggest that CVD TaN can be used as the gate electrode on ultra thin gate oxide in self-aligned gate-first CMOS processing.