Highly uniform resistive switching characteristics of Ti/TaOx/ITO memristor devices for neuromorphic system

In this study, we focused on the uniformity of resistance states of Ti/TaOx/ITO devices and the possibility of using them in neuromorphic applications under DC and pulse measurement conditions. The thickness and chemical composition of the devices was verified by transmission electron microscopy (TEM). First, the I-V curves of the devices were controlled with the compliance current and reset voltage. In addition, the multi-level characteristics were demonstrated through DC sweeps and pulses for high-density memory and neuromorphic systems. The linearity of potentiation and depression was then improved to seek high accuracy of pattern recognition in a neural network. Finally, spike-timing-dependent plasticity (STDP) was performed (including potentiation and depression) to mimic Hebbian learning of the nerve system.