Electrical transport features in Fe_3O_4/SiO_2-Si hybrid structures

摘要

The temperature dependencies of the resistivity of planar structures Fe_3O_4/SiO_2-Si, with Fe_3O_4 films of different thicknesses, were investigated. In the temperature range below 125 K, an anomalous decrease in the resistivity was observed. This effect is explained by switching of the conductance channel from the Fe_3O_4 film to the inversion layer of Si substrate due to the field-assisted tunneling of carriers through the semi-insulating Fe_3O_4/SiO_2 double insulator. Confirmation was obtained by the current-voltage characteristics measured at 80 K. It was found that current-voltage characteristics are S-shaped and correspond to the MIS switch diode.