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

摘要

Metal-oxide-semiconductor field-effect transistors (MOSFETs) were fabricated with amorphous Al_2O_3 and HfO_2/SiO_x-Si gate stacks, grown by molecular beam deposition. As and In oxides were observed at the Al_2O_3/In_(0.17)Ga_(0.83)As interface, whereas no oxides were detected on the Si-passivated In_(0.17)Ga_(0.83)As surface after HfO_2 deposition. Traces of As were found in both gate stacks. Si-passivated MOSFETs, with a drain current of 2.8 × 10~3 μA/mm at V_g-V_t=2.0 V, V_d = 1.0 V, I_(on)/I_(off)=1 × 10~7, and inverse subthreshold slope of 98-120 mV/decade, show superior performance with respect to devices without Si interlayer.