Enhanced Electrical Performance of Structurally Engineered Memristor Devices with Multi-Stacked Indium Zinc Oxide Films

Abstract

A structurally engineered memristor architecture based on metal-oxide materials has lasting significance for the nonvolatile and high storing velocity of next-generation nonvolatile memories. A memristor device based on multi-stacked indium zinc oxide (IZO) structure is fabricated using a solution process. An Al/three-multi-stacked IZO/TiO2/Al memristor device is fabricated with an In/Zn solution molar ratio of 7:3 with a repetitious spin-coating and annealing process. The amorphous TiO2 layer is prepared by atomic layer deposition with a low deposition temperature of 200 degrees C. The layers of IZO thin films in the memristor are raised from a single layer to three layers for intentional control of the concentration of oxygen vacancies, which play an important role in improving the electrical performance of memristor devices. The memristor exhibits uniform and reproducible resistance switching behavior with low-resistance state (LRS) and high-resistance state (HRS) voltage sweeps and shows excellent retention performance. The resistive switching phenomenon for an Al/multi-stacked IZO/TiO2/Al memristor device is explained from an analysis of the current-voltage characteristics and the impact of various IZO layers. This study also suggests that some other appropriate metal oxide thin films with good resistive-switching performance can be used to prepare structurally enhanced memristor devices.