Excellent frequency dispersion of thin gadolinium oxide high-$k$ gate dielectrics

In this letter, we reported a high-$k$ gadolinium oxide $(Gd2O3)$ gate dielectric formed by reactive rf sputtering. It is found that the $Gd2O3$ gate dielectric film exhibits excellent electrical properties such as low leakage current density, high breakdown voltage, and almost no hysteresis and frequency dispersion in $C‐V$ curves comparable to that of $HfO2$ film. This indicates that postprocessing treatments can reduce a large amount of interface trap and can passivate a large amount of trapped charge at defect sites.