Fully-transparent resistance switching memristor based on indium-tin-oxide material

With the potential to act as the next generation of non-volatile memory, resistive random access memory (RRAM) not only has stable and excellent electrical characteristics, but can also be used in such versatile applications as neuron computing and logic circuit design. However, material selection for RRAM devices to accomplish the metal-insulator-metal (MIM) structure which initiates the resistance switching (RS) mechanism is incomplete because of the many different material characteristics between the metal and insulator. In this work, we demonstrate a via-hole structure, full transparent RRAM (TRRAM) with indium-tin-oxide (ITO) acting as both electrode and middle insulator in the ITO/ITOX/ITO structure. The originally conductive ITO thin film successfully acts as an insulator after a supercritical fluid (SCF) oxidation treatment. This all-ITO RRAM device exhibits superb electrical performance and excellent environmental stability to high temperature without significant degradation in its RS characteristics. In addition, the ITO-based TRRAM also displays stable performance under different light illumination conditions. Another ITO-based TRRAM constructed on soft polyimide (PI) substrate has also been demonstrated. The present all-ITO TRRAM is not only of great interest for future stable transparent electron applications, but it also provides a guideline for the simplification of material selection for transparent electron devices.