Metal-Gate/High-$kappa$/Ge nMOS at Small CET With Higher Mobility Than $hbox{SiO}_{2}/hbox{Si}$ at Wide Range Carrier Densities

摘要

High-performance $hbox{TaN/TiLaO/La}_{2}hbox{O}_{3}/hbox{SiO}_{2}/ hbox{(111)}$-Ge nMOSFETs show high mobility of 432 $ hbox{cm}^{2}/hbox{V} cdot hbox{s}$ at $hbox{10}^{13} hbox{cm}^{-2}$ 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 $hbox{SiO}_{2}/hbox{Si}$ 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, $hbox{SiO}_{2}$ interfacial layer, and $hbox{YbGe}_{x}/hbox{n-Ge}$ contact.