Effect of Gamma Irradiation on the Structure, Morphology, and Memristive Properties of CVD Grown ReS2 Thin Film

Abstract

AbstractIn this work, effect of gamma irradiation on chemical vapor deposition grown ReS2 thin films vis‐a‐vis change in its structure, morphology, chemical composition, and memristive behaviour is reported to assess its radiation hardness for space applications. High‐resolution transmission electron micrographs and selected area electron diffraction pattern infer polycrystalline to amorphous phase transition and increase in the number of grain boundaries (GBs) after exposure to 25 kGy of gamma radiation. X‐ray photoelectron spectroscopy and low‐temperature photoluminescence measurements reveal the formation of sulfur vacancies (SV) accompanied with partial oxidation of film. Memristors are then fabricated on the as‐grown film using different metal electrodes, which are Ag, Pt, and Ti in lateral geometry, and their resistive switching (RS) mechanism is studied along with the impact of gamma irradiation. RS is attributed to the formation of conducting filaments due to GB‐mediated migration of metal ions, SV, and oxygen ions from the partially oxidized film. Furthermore, irradiation is found to increase current in the high resistance state of the device, which subsequently reduces the memory window. This impact is observed to be consistent across all the devices which validates the effect of irradiation irrespective of the nature of the metal electrode used.