Strategic allocation of two-dimensional van der Waals semiconductor as an oxygen reservoir for boosting resistive switching reliability

2-dimensional materials are highlighted in various electronic device applications due to their tunable and unique anisotropic physical characteristics induced by inherent low-dimensional nature. Herein, a 2-dimensional layered structure of SnS₂ is rationally adopted as an oxygen reservoir layer in a typical transition metal oxide based resistive switching device. The resistive switching media of stacked SnS₂/TiO₂ and lamella-like SnS₂·TiO₂ show 100 and 250 times higher endurance characteristics than that of individual TiO₂ based resistive switching device, respectively. Additionally, the characteristic of the operation voltage distribution for resistive switching also exhibits improved homogeneity in SnS₂-incorporated devices. Through the various microscopic analyses, it is revealed that the SnS₂ can store the mobile oxygen ions from TiO₂ in its interlayer, which facilitates boosted resistive switching characteristics. The oxygen reservoir layer is a crucial prerequisite for a reliable resistive switching device, however, the choice of materials that can serve as an oxygen reservoir is limited depending on the specific resistive switching system being used. This study demonstrates the 2-dimensional materials can be an unprecedented candidate for oxygen reservoir layers in resistive switching devices.