Improved ON/OFF Ratio in Interface-Type Memristors with Ion Irradiation-Induced Large Schottky Barrier for Neuromorphic Computing

Abstract

As a cutting-edge research direction in neuromorphic devices, interface-type (IT) memristors with leveraging interfacial engineering for resistive switching owing to the filament-free switching, low power dissipation, and high scalability. However, the trap states governing the interfacial Schottky barrier often exhibit a discrete and stochastic distribution. In this paper, the ion irradiation technology is used to control the interface Schottky barrier by regulating the defects near the surface of Nb:SrTiO 3 (NSTO). The device with the fluence of 1×10 12 cm -2 maintains good stability, excellent cyclic endurance characteristics and increases the on/off radio by an order of magnitude (from 10 5 to 10 6 ). Meanwhile, it can well simulate the synaptic function and in the neurological system, the recognition accuracy of images reaches 94.4%. These results indicate that ion irradiation can improve the resistance of IT memristors and be used in artificial synapses to establish the next generation of neural morphology calculation.