Interfacial resistive switching properties of Sr2TiO4/SrTiO3 heterojunction thin films prepared via sol-gel process

Layered perovskite SrO(SrTiO3)n (n = 1) and conventional perovskite SrTiO3 were fabricated as a heterojunction thin-film device. The Sr2TiO4/SrTiO3 heterostructure exhibited markedly improved resistive switching (RS) properties over single-phase Sr2TiO4 and pure strontium titanate. The other characteristics of the heterostructure, including stabilisation, high-pressure performance, and fatigue resistance, were investigated. The results showed a switch ratio of over 102, indicating a good RS effect. Various characterisation methods, such as Xray diffraction, field emission scanning electron microscopy, and atomic force microscopy, were applied to analyse the crystal phase and surface morphology of the Sr2TiO4/SrTiO3 heterojunction thin film. The interfacial conduction mechanism was explained with an appropriate diagram. This study is the first to apply a firstprinciples analysis based on the density functional theory to elaborate the experimental results at the microlevel. The research provides a deeper understanding of the role of specific defects due to the heterostructure, which are strongly related to interface contact, and promotes the performance of Ruddlesden-Popper-phase strontium titanate, which has potential applications in resistive random access memory devices.

Automated summary

The research found that the Sr2TiO4/SrTiO3 heterostructure thin film exhibits excellent resistive switching properties, as well as good performance in stability, high-pressure resistance, and fatigue resistance. Various characterization methods were used to analyze the heterostructure, and the interfacial conduction mechanism was explained.