Conduction Mechanism in SrTiO 3 -Based Field-Effect Transistors

In this brief, we find that the previously reported performance improvement of HfO 2 /SrTiO 3 devices after argon bombardment may be attributed to the decrease of interface traps. With the greatly reduced interface trap density, the HfO 2 /SrTiO 3 device after argon bombardment shows remarkable reduction of turn-ON voltage shift with decreasing temperature, which is in contrast with the unbombarded HfO 2 /SrTiO 3 device. Though HfO 2 /SrTiO 3 devices behave like conventional transistors, Al 2 O 3 /SrTiO 3 devices show very different linear transfer characteristics, which may be due to the high density of shallow donor states near the Al 2 O 3 /SrTiO 3 interface. The exhibited SrTiO 3 -based device characteristics are studied by experiments and simulations. The simulations with drift-diffusion model reproduce the experimental results.