Reproducible resistance switching in polycrystalline NiO films

Abstract

Negative resistance behavior and reproducible resistance switching were found in polycrystalline NiO films deposited by dc magnetron reactive sputtering methods. Oxygen to argon gas ratio during deposition was critical in deciding the detailed switching characteristics of either bi-stable memory switching or mono-stable threshold switching. Both metallic nickel defects and nickel vacancies influenced the negative resistance and the switching characteristics. We obtained a distribution of low resistance values which were dependent on the compliance current of high-to-low resistance switching. At 200°C, the low-resistance state kept its initial resistance value while the high-resistance state reached 85% of its initial resistance value after 5×105s. We suggested that the negative resistance and the switching mechanism could be described by electron conduction related to metallic nickel defect states existing in deep levels and by small-polaron hole hopping conduction.

Origin and elimination of photocurrent hysteresis by fullerene passivation in CH3NH3PbI3 planar heterojunction solar cells

“…Such photocurrent hysteresis is also typically observed in many kinds of electronic devices, particularly defect-rich, organic-based electronic devices, which contain a non-negligible amount of charge traps 22 . The current hysteresis can be explained by the dynamic electric field/charge injection modulated charge trapping and detrapping processes and is intentionally designed for some functional electronic devices, such as bistable memory 23,24 . The photocurrent hysteresis decreases with a spun PCBM layer on top of a perovskite layer and completely disappears after annealing the PCBM layer for 45 min.…”

Resistive switching of rose bengal devices: A molecular effect?

“…Very often, it was assumed that the switching effect is localized in small spots ͑filaments͒. 18,20,26 Besides this filament approach to explain switching in simple oxides, there are different theories such as current transport through two different defect states for the on and off states 19,24 or the suppression of a tunneling barrier due to high currents. 22 To further verify that the switching effect we observe is strongly related to the switching of an oxide layer, another experiment was conducted.…”

“…Layers of alumium oxide and of other metal oxides such as TiO, NiO, HfO 2 , ZrO 2 , and V 2 O 5 have already been shown to exhibit bistable switching. [18][19][20][21][22][23][24][25] Even in ultrathin layers of aluminum oxide ͑thickness below 1 nm͒, two conduction states were found, 22 one Ohmic state and one tunneling state. However, the transition between these two states in the ultrathin layers was not continuous and was probably triggered by external noise.…”

Enhancement of Resistance Switching in Electrodeposited Co-ZnO Films

“…Therefore, the primary requirement for RRAM is to develop a material that possesses resistive switching effect. To date, a number of materials have been found to have resistive switching behavior, for example, ferromagnetic oxide (Pr 1−x Ca x MnO 3 ), doped perovskite oxide (SrZrO 3 ), and binary transition metal oxide (TiO 2 , NiO, ZnO, and Cu 2 O) [1,2,4,6,[8][9][10][11]. Among these materials, only the transition metal oxides are transparent to the visible light due to their large optical band gap.…”