Diode-like behavior of I-V curves of CoFe-(Al-O)/Si(100) granular thin films

In this study, the electrical performance of (Co70Fe30)x(Al-O)1−x (where x=0.1 and 0.3) granular thin films sputtered on Si(1 0 0) substrates, which were subsequently annealing at 350 °C for 1 h in vacuum, was investigated. The millimeter-sized samples were installed in an in-plane lateral Ag electrode configuration on the surface. The current-voltage (I-V) characteristics were measured in bias voltages of approximately ±7 V. The I-V curves demonstrated the so-called large Coulomb gaps and diode-like asymmetric behavior similar to a Zener diode-type rectification. This remarkable behavior was evaluated using the most suitable transport models. Results suggest that an effective magnetic diode could be fabricated from millimeter-sized magnetic granular thin films.