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

The transition metal oxide NbO
₂
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 (γ-ray) radiation on a Pt/NbO
_x
/Pt selector device using electrical characterization and an X-ray photoelectron spectroscopy (XPS). The NbO
_x
devices were irradiated with
⁶⁰
Co γ-rays to a maximum dose of 5 Mrad (NbO
₂
). The experimental results show that the threshold switching behavior can withstand the 5 Mrad (NbO
₂
) without significant change in the switching parameters. The XPS results reveal that there are mixed NbO
₂
and Nb
₂
O
₅
phases in the NbO
_x
thin film. After 5 Mrad (NbO
₂
) γ-ray irradiation, the peak intensity of NbO
₂
increases and the peak intensity of Nb
₂
O
₅
decreases in the XPS spectra, probably due to the reduction of Nb
₂
O
₅
under radiation. Nevertheless, the electrical properties of the NbO
_x
-based selector have remained after 5 Mrad (NbO
₂
) γ-ray irradiation, indicating the potential use of the NbO
_x
-based selector device in aerospace applications.