Variability Improvement by Interface Passivation and EOT Scaling of InGaAs Nanowire MOSFETs

High-performance InGaAs gate-all-around (GAA) nanowire MOSFETs with channel length (L_ch) down to 20 nm are fabricated by integrating a higher k LaAlO₃-based gate-stack with an equivalent oxide thickness of 1.2 nm. It is found that inserting an ultrathin (0.5 nm) Al₂O₃ interfacial layer between the higher k LaAlO₃ and InGaAs can significantly improve the interface quality and reduce device variation. As a result, a record low subthreshold swing of 63 mV/dec is demonstrated at sub-80-nm L_ch for the first time, making InGaAs GAA nanowire devices a strong candidate for future low-power transistors.