Energy efficient short-term memory characteristics in Ag/SnO_x/TiN RRAM for neuromorphic system

In this work, we demonstrate the short-term memory effects of an Ag/SnO_x/TiN memristor device using the spontaneous reset process for a neuromorphic system. The thickness and chemical properties of the SnO_x layer are investigated via transmission electron microscopy and X-ray photoemission spectroscopy. The non-volatile and volatile memory properties are determined by the forming process, which is verified by the retention test. The conductance change increases as the interval between the pulses decrease because of the reduction of the spontaneous current decay. Moreover, paired-pulse facilitation (PPF) characteristics are demonstrated, where the PFF index decreases with an increase in the pulse interval. We first investigated potentiation with the application of set pulses and depression without reset pulses is examined for the neuromorphic system. With this pulse, we successfully implemented high-performance reservoir computing that has a range from [0000] to [1111] using the short-term memory characteristics of the Ag/SnO_x/TiN device.