Impact of Temperature on the Resistive Switching Behavior of Embedded $\hbox{HfO}_{2}$-Based RRAM Devices

A Memristor as Multi-Bit Memory: Feasibility Analysis

“…However, there are remaining challenges for quantizing the resistance of the memristor into discrete states at standard conditions. Deviations from the programmed resistance value are expected mostly due to temperature effects [27]. An ensemble of memristor devices is expected to produce even higher level of variations due to uncertainty in device critical dimensions and due to other small variations between (presumably identical) devices.…”

Quantum point contacts and resistive switching in Ni/NiO nanowire junctions

“…, where x is the location of the filament constriction as measured from the carrierinjecting (cathodic) nanowire and t ox is the oxide thickness. 31 In NiO thin films, it is suggested that conducting filaments grow from the cathode to the anode, 4 so we expect the filament constriction to be located within the oxide of the anodic nanowire. Using c ¼ 1, we find that the data in Figure 2 If the barrier UðTÞ is known, the radius of the filament constriction at its narrowest point can be estimated through the following equation:…”

“…Based on current-voltage (IV) and temperature-dependent resistance (R(T)) data, the metallic LRS behaves as a conventional metallic resistance in series with a small barrier, while the semiconducting LRS behaves as an atomically thin quantum point contact (QPC). [30][31][32][33][34][35] QPC conduction has been previously observed in HfO 2 devices, 34,36 but has not been documented in NiO systems. These observations suggest that the metallic (semiconducting) LRS derives from wide (narrow) filament constrictions that are preferentially achieved by executing either a single-or multi-step electroformation process.…”

“…44 However, this behavior is in good agreement with the temperature trends predicted by the QPC model, which describes conduction through an atomically thin bottleneck constriction. 31,32,35 In this framework, quantum confinement at the constriction results in a local potential barrier, commonly modeled as parabolic in shape, and a series of energy subbands where conduction occurs only through the lowest level. 35 The temperaturedependent IV relationship for a QPC with a single conducting channel is given by…”

“…This barrier is temperature dependent, UðTÞ ¼ U o À hT, where U o is the 0 K effective barrier height and the slope h describes the reduction of barrier height due to increasing atomic vibrations at elevated temperatures. 31 The result is a current, and thus a resistance, that varies exponentially with temperature, IðTÞ / exp ðÀa½U o À hTÞ. , where x is the location of the filament constriction as measured from the carrierinjecting (cathodic) nanowire and t ox is the oxide thickness.…”