Coexistence of Long-Term Memory and Short-Term Memory in an SiNx-Based Memristor

Abstract

Complementary metal oxide semiconductor-compatible Ni/SiNx/SiO2/Si devices present good synaptic characteristics for neuromorphic systems on the hardware level. The SiO(2)layer detectable by X-ray photoelectron spectroscopy can improve stability and low-power resistive switching. The properties of nonvolatile and volatile memory are determined by the compliance current (strength of the conducting path) during DC voltage sweep. For more practical operation, repeated pulse inputs are applied to the memristor to implement both long-term plasticity and short-term plasticity, determined by pulse interval time. A shorter interval time between two pulses leads to larger paired-pulse facilitation related to short-term plasticity. Finally, ten cycles of potentiation and depression are demonstrated by well-designed pulse schemes. The coexistence of long-term and short-term memory in a Ni/SiNx/SiO2/Si device can provide more flexibility in device design in future neuromorphic systems on the hardware level.