Crack–Defect Landscapes Enable Multimodal Memristive Switching in WS 2 Mono‐Bilayers

ABSTRACT While nano or micro cracks are often unavoidable during the scalable growth of 2D materials, their role and interactions with vacancies in facilitating variable memristive switching are generally overlooked in device applications. Addressing device‐to‐device and cyclic variability in 2D memristor demands a mechanistic understanding of vacancy dynamics and their conduction pathways. We unveil how point defects and intergranular cracks modulate dynamic memristor behavior in mono‐bilayer WS 2 lateral devices associated with varied sulfur vacancy concentrations, ranging from nearly pristine to ∼10 14 cm −2 , as confirmed by aberration‐corrected electron microscopic and spectroscopic investigations. The crack boundaries act as preferential sites for vacancy migration and charged species, facilitating resistive switching in polycrystalline like WS 2 mono‐bilayers. The observed conductance switching originate from Schottky barrier modulation at the WS 2 metal interface and the redistribution of vacancies within the channel. To enhance the device performance, controlled thermal annealing in distinct environments has been performed. The devices exhibited distinguishable switching for 800 cycles with consistent resistance ratios followed by onset of toggling state and later collapsing to trap state. These findings establish a direct correlation between atomic‐scale defects and memristive performance, providing fundamental insights into vacancy–crack interactions that govern charge transport and stability in 2D materials.