Low Temperature Sol-Gel Processed Zirconium Oxide Based Transparent Resistive Random Access Memory Devices

Abstract

In this work, solution-processed ZrO2-based resistive random-access memory (RRAM) device with ITO (Indium Tin Oxide) as a bottom electrode (BE) was fabricated at a low thermal budget by sol-gel spin coating technique. The grown devices (ZrO2/ITO) were found to be amorphous by XRD measurements and exhibit 80% transmittance in the visible region. The resistive switching characteristics of solution-processed ZrO2 thin films were investigated. The W/ZrO2/ITO device exhibits good cyclic endurance with an on-off ratio (~10) and reliable switching and good retention at room temperature. The conduction mechanism for the low resistance state is ohmic, whereas the conduction mechanism of the high resistance state is ohmic at low applied voltages, while a space charge limited conduction (SCLC) at the high applied voltages. The combined ohmic and space charge limited conduction mechanisms together indicate that the RS behavior in the ZrO2 layer is due to the formation and rupture of conducting filaments. Results suggest that solution-processed ZrO2 has great potential to develop transparent and flexible resistive random access memory devices.