Higher Gate Capacitance Ge n-MOSFETs Using Laser Annealing

By applying laser annealing (LA) on both gate dielectrics and source/drain activation, the TaN/ZrO₂/La₂O₃/SiO₂ on Ge n-MOSFETs shows a high gate capacitance density, a small n⁺/p-junction ideality factor of 1.10, a small subthreshold swing (SS) of 106 mV/dec, and a good high-field mobility of 285 or 340 cm²/V·s after gate leakage correction at 1 MV/cm, at a small 0.95-nm equivalent oxide thickness (EOT). To the best of our knowledge, this is the first demonstration of significantly high gate capacitance in MOSFETs by LA. This is also the highest 1-MV/cm mobility at the smallest EOT of Ge n-MOSFETs and better than the SiO₂/Si universal mobility.