Improved gate-control in InAs nanowire structures by the use of GdScO3 as a gate dielectric

We investigated the properties of gadolinium scandate (GdScO3) as a gate dielectric for top-gate electrodes on undoped InAs nanowires. It is demonstrated that due to the high dielectric constant of GdScO3 (k=22), a better control of the conductance of the nanowire is achieved compared to a reference SiO2-isolated back-gate electrode. We analyzed the output and transfer characteristics of top-gate-controlled InAs wires at room temperature and at temperatures down to 4 K. Owing to the good coverage of the InAs nanowire by the 50-nm-thick GdScO3 layer, which was deposited by pulsed-laser deposition, the gate leakage current is sufficiently suppressed.