Study On Resistance Switching Characteristics Of Photo Regulated TiO₂ Composite Films

TiO₂,as a typical binary metal oxide,has been the key material in the field of resistive random access memories(RRAM).Because of its simple structure,various preparation crafts,excellent resistance characteristics and flexibility,TiO₂ is one of the most competitive materials for the next generation of nonvolatile memory.Different preparation technology and device structure make different optical and electrical properties of TiO₂ based RRAM.The photoconductive effect of TiO₂ under optical modulation has been widely explored by condensed matter physics.If combined with the resistance characteristics under electric modulation,it will broaden the way for its multi-function application.The paper focuses on the study of the resistance characteristics of different morphology and structure devices based on TiO₂.After the thin film device is made by simple preparation method,the I-V characteristic curve of the sample is tested,and the resistance state is regulated by the joint action of the light field and electric field,and the conductive mechanism is studied.The specific research contents are as follows:1.Au/Au-TiO₂/FTO sandwich structure resistive devices were prepared by sol-gel method and spin coating method.The resistance characteristics of Au nanoparticles were studied by fitting I-V curves to analyze the conductivity mechanism,and the effect of Au nanoparticles embedding and illumination conditions on their resistance characteristics was determined.2.Au/TiO₂/FTO capacitive coupling resistance devices were prepared by sol-gel method and spin coating method.The relationship between the resistive change phenomenon and the capacitance variation phenomenon in the structure was analyzed,and the uncompressed I-V curves were studied by applying and changing the illumination conditions.The ion migration model is established to determine the behavior of oxygen vacancy particles under voltage and light modulation.3.The results show that the simulated resistance characteristics of Au/TiO₂ nanotubes/Ti sandwich structure are produced by anodizing.The simulated resistance characteristics are due to the capture/de-capture of electrons by oxygen vacancy,and the conversion to digital mode by the irradiation of 375 nm laser.This phenomenon is attributed to the activation of more oxygen vacancy and the desorbing of surface oxygen under light condition.