Multi-Level Resistive Switching of Pt/HfO2/TaN Memory Device

This work characterizes resistive switching and neuromorphic simulation of Pt/HfO2/TaN stack as an artificial synaptic device. A stable bipolar resistive switching operation is performed by repetitive DC sweep cycles. Furthermore, endurance (DC 100 cycles) and retention (5000 s) are demonstrated for reliable resistive operation. Low-resistance and high-resistance states follow the Ohmic conduction and Poole–Frenkel emission, respectively, which is verified through the fitting process. For practical operation, the set and reset processes are performed through pulses. Further, potentiation and depression are demonstrated for neuromorphic application. Finally, neuromorphic system simulation is performed through a neural network for pattern recognition accuracy of the Fashion Modified National Institute of Standards and Technology dataset.

Bias Polarity Dependent Threshold Switching and Bipolar Resistive Switching of TiN/TaOx/ITO Device

In this work, we demonstrate the threshold switching and bipolar resistive switching with non-volatile property of TiN/TaOx/indium tin oxide (ITO) memristor device. The intrinsic switching of TaOx is preferred when a positive bias is applied to the TiN electrode in which the threshold switching with volatile property is observed. On the other hand, indium diffusion could cause resistive switching by formation and rupture of metallic conducting filament when a positive bias and a negative bias are applied to the ITO electrode for set and reset processes. The bipolar resistive switching occurs both with the compliance current and without the compliance current. The conduction mechanism of low-resistance state (LRS) and high-resistance state (HRS) are dominated by Ohmic conduction and Schottky emission, respectively. Finally, threshold switching and bipolar resistive switching are verified by pulse operation.

Resistive Switching in Electrodeposited Prussian Blue Layers

Prussian blue (PB) layers were electrodeposited for the fabrication of Au/PB/Ag stacks to study the resistive switching effect. The PB layers were characterized by different techniques to prove the homogeneity, composition, and structure. Electrical measurements confirmed the bipolar switching behavior with at least 3 orders of magnitude in current and the effect persisting for the 200 cycles tested. The low resistance state follows the ohmic conduction with an activation energy of 0.2 eV.

Non-ohmic conduction in sodium bismuth titanate: the influence of oxide-ion conduction

A maximum conductivity enhancement of >2000% is achieved in Na0.5Bi0.51TiO3.015 under a small dc bias, in which the highly mobile oxygen ions and the electrode reactions play a critical role.

SYSTEMATIC EXPLORATION OF THE EFFECTS OF CR-DOPING ON MICROSTRUCTURE, INSULATING, AND FERROELECTRIC PROPERTIES OF BiFeO3 THIN FILM

BiFe[Formula: see text]CrxO3 ([Formula: see text]BFCO, [Formula: see text], 0.02, 0.03, 0.04, 0.05) thin films were successfully fabricated onto Pt(111)/TiO2/SiO2/Si substrate via a solgel process. The correlation between microstructure and insulating, ferroelectric properties of [Formula: see text]BFCO thin films are investigated. The leakage behavior for all the thin films is in accordance with the Ohmic conduction and FN Tunneling emission during low and high electric field region, respectively. Compared with the pure BFO, all the thin films with Cr[Formula: see text] doping possess reduced leakage current density by 1–2 orders of magnitude, with the lowest value approximately 10[Formula: see text] at 200[Formula: see text]kV/cm. Moreover, the 0.04BFCO thin film exhibits the maximum remanent polarization ([Formula: see text]) value of 29.8[Formula: see text][Formula: see text]C/cm2 with a great fatigue behavior, which could be ascribed to the absence of impurity phase and reduced leakage current.