Total Ionizing Dose Effects of Gamma-Ray Radiation on NbOx Based Selector Devices for Crossbar Array Memory

Abstract

The transition metal oxide NbO2 is regarded as a promising selector device to be integrated with resistive random access memory for the high-density crossbar array architecture. Understanding its total ionizing dose (TID) response would help assess the reliability of using this selector device in radiation environments. In this paper, we investigate the TID effect of gamma-ray ( $\gamma$ -ray) radiation on a Pt/NbOx/Pt selector device using electrical characterization and an X-ray photoelectron spectroscopy (XPS). The NbOx devices were irradiated with 60Co $\gamma$ -rays to a maximum dose of 5 Mrad (NbO2). The experimental results show that the threshold switching behavior can withstand the 5 Mrad (NbO2) without significant change in the switching parameters. The XPS results reveal that there are mixed NbO2 and Nb2O5 phases in the NbOx thin film. After 5 Mrad (NbO2) $\gamma$ -ray irradiation, the peak intensity of NbO2 increases and the peak intensity of Nb2O5 decreases in the XPS spectra, probably due to the reduction of Nb2O5 under radiation. Nevertheless, the electrical properties of the NbOx-based selector have remained after 5 Mrad (NbO2) $\gamma$ -ray irradiation, indicating the potential use of the NbOx-based selector device in aerospace applications.