Influence of band parameter of gate dielectrics on the ballistic performance at same EOT

Abstract

Different high-k dielectrics have been supposed to provide same device performance if their physical thickness are not equal but equivalent, called “Equivalent oxide thickness” (EOT). For ultra thin body (UTB) devices like XOI, despite of EOT, conduction band offset (ΔE_C) at gate oxide-channel interface dominates the ballistic performance. In case of In_0.3Ga_0.7Sb XOI nFET using Al₂O₃ and HfO₂ with 0.5 nm EOT, we show the threshold voltage decreases and the subthreshold slope (SS) increases with increase in ΔE_C.