Resistive switching characteristics in dielectric/ferroelectric composite devices improved by post-thermal annealing at relatively low temperature

We have investigated the effects of post-thermal annealing on the resistive switching characteristics of dielectric/ferroelectric composite devices of SrRuO3/LaFeO3/Bi1−δFeO3/SrRuO3. Annealing of the devices above 85 °C enhanced the hysteresis of the current–voltage characteristics, resulting in an increase in the resistive switching ratio. After post-thermal annealing at 200 °C, devices with a thicker LaFeO3 layer exhibited a larger resistive switching ratio, and the device-to-device variation in the resistive switching ratio decreased as the LaFeO3-layer thickness was increased. The pulsed-voltage-induced resistive switching characteristics, such as the resistive switching ratio and the switching speed, were also improved by post-thermal annealing.