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In this review, we provide an overview of our work in resistive switching mechanisms on oxide-based resistance random access memory (RRAM) devices. Based on the investigation of physical and chemical mechanisms, we focus on its materials, device structures, and treatment methods so as to provide an in-depth perspective of state-of-the-art oxide-based RRAM. The critical voltage and constant reaction energy properties were found, which can be used to prospectively modulate voltage and operation time to control RRAM device working performance and forecast material composition. The quantized switching phenomena in RRAM devices were demonstrated at ultra-cryogenic temperature (4K), which is attributed to the atomic-level reaction in metallic filament. In the aspect of chemical mechanisms, we use the Coulomb Faraday theorem to investigate the chemical reaction equations of RRAM for the first time. We can clearly observe that the first-order reaction series is the basis for chemical reaction during reset process in the study. Furthermore, the activation energy of chemical reactions can be extracted by changing temperature during the reset process, from which the oxygen ion reaction process can be found in the RRAM device. As for its materials, silicon oxide is compatible to semiconductor fabrication lines. It is especially promising for the silicon oxide-doped metal technology to be introduced into the industry. Based on that, double-ended graphene oxide-doped silicon oxide based via-structure RRAM with filament self-aligning formation, and self-current limiting operation ability is demonstrated. The outstanding device characteristics are attributed to the oxidation and reduction of graphene oxide flakes formed during the sputter process. Besides, we have also adopted a new concept of supercritical CO2 fluid treatment to efficiently reduce the operation current of RRAM devices for portable electronic applications.

This study investigates the electrical performance of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors with Ga2O3 gate dielectric and applied on deep-ultraviolet phototransistors. To reduce the leakage current, we introduce the SiO2 interlayer dielectric, which effectively reduces the off-current. Under the illumination of 250 nm, the measured responsivity of the device was 3.2 A/W at an applied gate bias of 0 V. The photo-generated carriers were injected into the channel by the applied electric field and Fowler-Nordheim tunneling. A large photocurrent and responsivity can be obtained which is attributed to the high mobility of the a-IGZO channel.

In this work, a TiN/HfO2/ITO memory device is fabricated, which shows stable bipolar resistive switching behavior, as well as excellent data retention and good endurance. Moreover, a very low SET voltage of 0.2 V is achieved with a self-compliance current effect. The result brings about an obvious reduction in SET power to 160 µW, which is crucial for future high-density resistive switching memories. On the basis of the conducting filament theory, a possible resistive mechanism is discussed to explain the low SET voltage and self-compliance current phenomenon.