Study on a conductive channel of a Pt/NiO/Pt ReRAM by bias application with/without a magnetic field

Resistive random access memories (ReRAMs) have attracted much attention as a next-generation non-volatile memory. We focused on a NiO-based ReRAM in this study because it contains the magnetic element Ni. As-fabricated devices exhibit ideal memristive operation. When bias was swept in one polarity, the resistance decreased by repeating the bias sweeping. Conversely, by changing the polarity of the sweeping bias, the resistance gradually increased by repeating the bias sweeping. A steep increase in current was observed when continuing bias sweeping in the polarity that decreased the resistance. The resistance after that was lower than 12.9 kΩ, which suggests the formation of a Ni atom chain. Conductance quantization, with a unit of 2e²/h, also suggested the said formation. When a magnetic field was applied, the unit of conductance quantization appeared to change from 2e²/h to e²/h. (author)