Metal-Gate/High-kappa/Ge nMOS at Small CET With Higher Mobility Than SiO2/Si at Wide Range Carrier Densities

Abstract

High-performance TaN/TiLaO/La2O3/SiO2/(111)-Ge nMOSFETs show high mobility of 432 cm(2)/V . s at 10(13) cm(-2) carrier density (N-s), good 1.05 junction ideality factor, and small subthreshold swing of 101 mV/dec, at a small 1.1-nm capacitance-equivalent thickness (CET). This is the first report of higher mobility in the Ge nMOSFET than SiO2/Si universal mobility at wide medium-high N-s range and small CET of 1.1 nm, which is attributed to using the (111)-Ge substrate, 30-ns laser annealing, SiO2 interfacial layer, and YbGex/n-Ge contact.