Impact of temperature on conduction mechanisms and switching parameters in HfO2-based 1T-1R resistive random access memories devices

In this work, the impact of temperature in the range from -40 to +150 °C on the leakage mechanism and resistive switching voltages of 1T-1R HfO2-based devices is investigated. By using incremental step pulses with an additional read and verify algorithm, the devices are switched from the high resistive state (HRS) to the low resistive state (LRS) and vice versa. In the HRS, the leakage current values are not affected by the temperature, suggesting a tunnel-like conduction mechanism through the filament constriction. By applying the quantum-point contact model, this temperature independence is attributed to compensation between the width and the height variations of the tunnel barrier. In contrast to the HRS, the leakage currents values of the LRS are decreasing linearly with raising temperature, suggesting a metal-like conduction mechanism. Therefore, the on/off ratio is slightly decreasing with increasing temperature. Regarding the switching voltages, no impact of temperature was found, ensuring stable switching cycles of the devices in the relevant temperature range for applications.