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The technologies of 3D vertical architecture have made a major breakthrough in establishing high‐density memory structures. Combined with an array structure, a 3D high‐density vertical resistive random access memory (VRRAM) cross‐point array is demonstrated to efficiently increase the device density. Though electrochemical migration (ECM) resistive random access (RRAM) has the advantage of low power consumption, the stability of the operating voltage requires further improvements due to filament expansions and deterioration. In this work, 3D‐VRRAM arrays are designed. Two‐layered RRAM cells, with one inert and one active sidewall electrode stacked at a cross‐point, are constructed, where the thin film sidewall electrode in the VRRAM structure is beneficial for confining the expansions of the conducting filaments. Thus, the top cell (Pt/ZnO/Pt) and the bottom cell (Ag/ZnO/Pt) in the VRRAM structure, which are switched by different mechanisms, can be analyzed at the same time. The oxygen vacancy filaments in the Pt/ZnO/Pt cell and Ag filaments in the Ag/ZnO/Pt cell are verified. The 40 nm thickness sidewall electrode restricts the filament size to nanoscale, which demonstrates the stability of the operating voltages. Additionally, the 0.3 V operating voltage of Ag/ZnO/Pt ECM VRRAM demonstrates the potential of low power consumption of VRRAM arrays in future applications. [ABSTRACT FROM AUTHOR]

Bacteria‐mediated tumor therapy (BMTT) has been known for decades; however, its clinical use is inhibited by its association with infections. To address this issue, a spiky, bacterium‐like metal–organic framework (MOF), which can replicate the functional responses of BMTT without its adverse side‐effects, is proposed. MOFs are synthesized in a solvothermal reaction of aluminum sulfate, ruthenium chloride hydrate, and 2‐aminoterephthalic acid; they have a spherical morphology or many nanospikes on their surfaces, depending on the reaction temperature. Both spherical and spiky MOFs can function as photothermal agents, converting absorbed optical energy into local heat. Owing to their higher surface area of interaction, spiky MOFs are more easily phagocytosed by macrophages than are spherical MOFs, strengthening their immune responses. Moreover, when injected intratumorally, spiky MOFs reside significantly longer than spherical ones, enabling their use in repeated photothermal treatments. The combination of in situ vaccination with intratumorally injected bacterium‐like MOFs under exposure to an near‐infrared laser and the immune checkpoint blockade of systemically administered αPD‐1 is evaluated in tumor‐bearing mice. The results indicate that the checkpoint blockade acts synergistically with in situ vaccination to provide diverse antitumor functions of BMTT, destroying a primary tumor and suppressing tumor recurrence and metastasis. [ABSTRACT FROM AUTHOR]