Synaptic plasticity of ZnO memristive structures for neuromorphic systems of AI

The work shows the results of multilevel resistive switching, as well as synaptic plasticity of TiN/ZnO/TiN memristive structures. Potentiation and depression at 200 voltage pulses with an amplitude of 1.8 V were demonstrated. It was shown that fabricated TiN/ZnO/TiN memristive structures demonstrate multilevel resistive switching with 5 resistive states and resistance ratio HRS/LRS at 1062 ± 35. Five resistive states were maintained for 10 000 s of operation time. Also, spike-timing-dependent plasticity with the asymmetric Hebbian rule at the pulse interval from -9 s to 9 s was demonstrated. The obtained results can be used for hardware implementation of neural networks, neuromorphic structures of robotic complexes, prostheses, and artificial intelligence systems.