Structural and electrical properties of fully strained (In,Ga)As field effect transistors with in situ deposited gate stacks

Metal-oxide-semiconductor field-effect transistors (MOSFETs) were fabricated with amorphous $Al2O3$ and $HfO2/SiOx–Si$ gate stacks, grown by molecular beam deposition. As and In oxides were observed at the $Al2O3/In0.17Ga0.83As$ interface, whereas no oxides were detected on the Si-passivated $In0.17Ga0.83As$ surface after $HfO2$ deposition. Traces of As were found in both gate stacks. Si-passivated MOSFETs, with a drain current of $2.8×103μA/mm$ at $Vg−Vt=2.0V$⁠, $Vd=1.0V$⁠, $Ion/Ioff=1×107$⁠, and inverse subthreshold slope of 98–120 mV/decade, show superior performance with respect to devices without Si interlayer.