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Perovskite‐oxide‐based capacitors, which exhibit high charge storage capacity, have attracted considerable attention as a potential candidate for overcoming the limitations of nanoscale integration. Unfortunately, a dead layer forms in these capacitors at the interface between the electrode and the dielectric, which degrades the charge storage capacity; thus, this layer has been extensively investigated. The dead layer in perovskite‐oxide‐based capacitors exhibits different characteristics depending on the electrode materials; however, a method for minimizing this layer is lacking. In this study, the charge storage capacity of a perovskite‐oxide‐based capacitor is evaluated considering the effect of the Ru and SrRuO3 top electrodes on the SrRuO3/Ba0.5Sr0.5TiO3 stack. Dead layers at the interface between each top electrode material and the dielectric are studied on the atomic scale. The results indicate that the Ru metal electrode causes oxygen to diffuse from the dielectric to the electrode, forming elongated perovskite oxide at the interface, which acts as a dead layer. However, minimizing the dead layer at the top interface increases the dielectric permittivity from 667 to 953. Consequently, the phenomenon and mechanism of the dead layer are intuitively identified. This study proposes a method to overcome the limitations of next‐generation dynamic random access memory (DRAM). [ABSTRACT FROM AUTHOR]

Notwithstanding its excellent properties such as high work function and low resistance, Ru has not been widely applied in the preparation of electrodes for various electronic devices. This is because of the occurrence of severe morphological degradation in the actual devices employing Ru. Herein, we investigated Ru chemistry for electrode application and the degradation mechanism of Ru during subsequent processes such as thin film deposition or thermal annealing. We revealed that subsurface oxygen induces Ru degradation owing to the alteration of Ru chemistry by the pretreatment under various gas ambient conditions and due to the growth behavior of TiO2 deposited via atomic layer deposition (ALD). The degradation of Ru is successfully ameliorated by conducting an appropriate pretreatment prior to ALD. The TiO2 thin film deposited on the pretreated Ru electrode exhibited a rutile-phased crystal structure and smooth surface morphology, thereby resulting in excellent electrical properties. This paper presents an important development in the application of Ru as the electrode that can facilitate the development of various next-generation electronic devices. [ABSTRACT FROM AUTHOR]

This study examines how service coupons influence the consumer trade-offs between price and perceived quality and, finally, how they affect consumer purchase intention. It also investigates the mediating role of the perceptions of performance and financial risks as well as the moderating effect of the service types (experience vs. credence services) on the determination of purchase intentions. The research model is tested by an experiment. The results are discussed in detail with future research implications. [ABSTRACT FROM AUTHOR]

Atomically thin two-dimensional (2D) materials-such as transition metal dichalcogenide (TMD) monolayers and hexagonal boron nitride (hBN)-and their van der Waals layered preparations have been actively researched to build electronic devices such as field-effect transistors, junction diodes, tunneling devices, and, more recently, memristors. Two-dimensional material memristors built in lateral form, with horizontal placement of electrodes and the 2D material layers, have provided an intriguing window into the motions of ions along the atomically thin layers. On the other hand, 2D material memristors built in vertical form with top and bottom electrodes sandwiching 2D material layers may provide opportunities to explore the extreme of the memristive performance with the atomic-scale interelectrode distance. In particular, they may help push the switching voltages to a lower limit, which is an important pursuit in memristor research in general, given their roles in neuromorphic computing. In fact, recently Akinwande et al. performed a pioneering work to demonstrate a vertical memristor that sandwiches a single MoS 2 monolayer between two inert Au electrodes, but it could neither attain switching voltages below 1 V nor control the switching polarity, obtaining both unipolar and bipolar switching devices. Here, we report a vertical memristor that sandwiches two MoS 2 monolayers between an active Cu top electrode and an inert Au bottom electrode. Cu ions diffuse through the MoS 2 double layers to form atomic-scale filaments. The atomic-scale thickness, combined with the electrochemical metallization, lowers switching voltages down to 0.1-0.2 V, on par with the state of the art. Furthermore, our memristor achieves consistent bipolar and analogue switching, and thus exhibits the synapse-like learning behavior such as the spike-timing dependent plasticity (STDP), the very first STDP demonstration among all 2D-material-based vertical memristors. The demonstrated STDP with low switching voltages is promising not only for low-power neuromorphic computing, but also from the point of view that the voltage range approaches the biological action potentials, opening up a possibility for direct interfacing with mammalian neuronal networks.