Synthesis of LaXO3 (X = Fe, Mn, Cr, Ni) Thin Films Using a Simple Spin Coating Set-Up for Resistive Switching Memory Devices

Abstract

This study focuses on the preparation of LaXO3(X=Fe,Mn,Cr,Ni) perovskite thin films using a simple set-up spin coating technique and the evaluation of their properties for application in switching memory devices. The properties of as-deposited films were thoroughly characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), UV-Vis spectroscopy, and a vibrating sample magnetometer (VSM). The results obtained revealed that the as-deposited films have a polycrystalline cubic structure. The film surfaces were uniform and densely packed without any voids, cracks, or pinholes. In addition, irregularly shaped grains were observed having an average size of 140, 120, 89, and 70 nm for LaFeO3, LaMnO3, LaCrO3, and LaNiO3 films, respectively. VSM analysis demonstrated that LaFeO3 film exhibited superior magnetic properties compared to the other films. Furthermore, memory devices with Au/LaXO3(X=Fe,Mn,Cr,Ni)/FTO structures were fabricated, and their I-V characteristics were measured. In order to assess their performance, an endurance test was conducted. The findings indicated that Au/LaFeO3/FTO device exhibited higher RHRSRLRS ratio (~7×105), low Set/Reset voltages, lower power consumption (2.7×10−4 W), and stable endurance with no significant degradation was observed in the LRS and HRS after 20 sweep cycles. These favorable parameters can be attributed to the reduced thickness, larger grain size, and excellent magnetic properties of the active-layer LaFeO3. Moreover, the conduction mechanism of the fabricated devices was investigated, revealing that the conduction in the LRS is primarily dominated by Ohmic behavior, while the HRS exhibited different conduction mechanisms.