Neutron Irradiation Damage Effects on the Ag:Ta 2 O 5 -Based High Speed Threshold Switching Memristors

Threshold switching (TS) memristors have emerged as promising candidates for artificial neurons in brain-inspired chips due to advantages of easy integration, high density, and low power consumption. However, in aerospace applications, their performances are susceptible to degradation caused by radiation, posing a threat to the reliability of brain-inspired chips. Currently, the radiation degradation laws and mechanisms of TS memristors characteristics are not yet fully understood. In this paper, we firstly investigate the radiation damage law and mechanisms of Ta₂O₅: Ag-based TS memristors based on neutron source. Then the impact of neutron irradiation on the spike firing frequency of Leaky Integrate-and-Fire (LIF) neurons based on these devices are simulated using PSpice. The results indicate that as the neutron irradiation fluence increases, holding voltage, high resistance state, and on/off ratio of the memristors remain basically unchanged while the threshold voltage increases and the switching speed decreases. When the neutron fluence reaches 4.5×10¹² n/cm², the threshold voltage and on/off time of the memristor increase to 1.10~1.58 V and 39/42 ns respectively, which results in more stringent conditions for the LIF neuron to generate spike frequencies. X-ray Photoelectron Spectroscopy analysis reveals that the main reason for the degradation of device performance is the suppression of silver ion migration by irradiation-induced silver interstitial atoms and oxygen vacancy defects. The research findings offer support for the development of radiation-hardened high-speed memristor-based neurons and brain-inspired chips.