Electrical and optical artificial synapses properties of TiN-nanoparticles incorporated HfAlO-alloy based memristor

Resistive switching behavior of sandwiched HfAlO/TiN-NP/HfAlO switching layer demonstrated in this work. Stable 10³ DC switching cycles achieved after incorporation of TiN-NPs, which were partially oxidized to form TiO_xN_y confirmed by X-ray photoelectron spectroscopy. The experiment predicted that TiO_xN_y/HfAlO interface acts as a weak spot and facilitated the rapture and formation of the conductive filaments. Also, gradual switching behavior between low resistance state and high resistance state improved after introducing atomic layer deposited TiN-NPs into the switching layer. Several synaptic properties have been studied, including potentiation/depression under different pulse schemes, spike-time-dependent plasticity, spike-rate-dependent plasticity at the frequency of 2 Hz to 200 Hz, and short-term plasticity under different pulse amplitudes. These properties demonstrated that ITO/ HfAlO/TiN-NP/HfAlO/ITO RRAM device is suitable for the neuromorphic application. Light-induced modulation of increasing current and relaxation behavior using a 405 nm laser source further confirms the possibility for light-induced random access memory devices.