Impact of substrate temperature on NiO thin films for resistive switching memory (ReRAM) memory devices

Abstract

In this research, we report the bipolar resistive switching (RS) behavior of NiO thin films at various substrate temperature between 300ºC to 400ºC. A non-vacuum spray pyrolysis method is adopted to deposit NiO thin film layers. The structural studies confirm that all the NiO thin films were polycrystalline in nature along with cubic structure. The micrograph analysis of the NiO thin film layers shows a homogeneous distribution of grain without voids and micro-cracks. The optical transmittance spectra reveals that NiO (375) sample exhibit maximum transparent (> 60 %) in the visible region. The NiO switching layers were sandwiched between bottom indium-doped tin oxide (ITO), and top silver (Ag) electrodes, and their RS behavior were examined. The fabricated ITO/NiO/Ag RS devices shows bipolar current (I)-voltage (V) behavior with calculated ON/OFF ratio of 1.5. Moreover, the observed RS bahaviour in the fabricated ITO/NiO/Ag devices was associated due to the formations and ruptures of conductive paths.
Keywords: Nickel oxide (NiO); formation and rupture; resistive switching (RS)