Memristors, also known as resistive switching devices, have great potential for applications in memory and neuromorphic systems. Understanding the switching mechanisms is crucial since ReRAM memories need to operate at high frequencies. It is known the reset transition is dominated by the conductive filament Joule heating. We have studied the reset transition in TiN/Ti/HfO2/W metal–insulator–metal memristors by applying constant power signals to different initial filament thicknesses, which were obtained using different initial low resistance states. The results show that power value controls the reset times, decreasing when the power is increased. On the other hand, larger resistances lead to faster reset transitions. These measurements have allowed us to obtain a value of the thermal resistance of the conductive filament. Moreover, we have observed the reset times as a function of the initial resistance and the power lies on a common plane, which allows us to estimate the transition time by fixing an initial resistance and a power value.
