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A model device based on an epitaxial stack combination of titanium nitride (111) and monoclinic hafnia (111) is grown onto a c‐cut Al₂O₃‐substrate to target the role of grain boundaries in resistive switching. The texture transfer results in 120° in‐plane rotated m‐HfO₂ grains, and thus, in a defined subset of allowed grain boundary orientations of high symmetry. These engineered grain boundaries thread the whole dielectric layer, thereby providing predefined breakdown paths for electroforming‐free resistive random access memory devices. Combining X‐ray diffraction and scanning transmission electron microscopy (STEM)–based localized automated crystal orientation mapping (ACOM), a nanoscale picture of crystal growth and grain boundary orientation is obtained. High‐resolution STEM reveals low‐energy grain boundaries with facing (112) and (121) surfaces. The uniform distribution of forming voltages below 2 V — within the operation regime — and the stable switching voltages indicates reduced intra‐ and device‐to‐device variation in grain boundary engineered hafnium‐oxide‐based random access memory devices.

Werbung durch Influencer:innen stellt für Jugendliche eine Herausforderung dar, da sich redaktionelle Inhalte eines Mediums (ohne Verkaufsabsicht) mit persuasiven Inhalten von Werbebotschaften (mit Verkaufsabsicht) verschränken. Der vorliegende Beitrag hat daher das Ziel, ein Erhebungsinstrument zu entwickeln, das die Kompetenz Jugendlicher im Umgang mit Influencer:innen-Marketing erfasst. Hierzu wurden bestehende Skalen zur Advertising Literacy übersetzt, an den Kontext von Influencer:innen-Marketing adaptiert und erweitert. Die resultierenden Items wurden anhand einer Stichprobe von 14- bis 18-Jährigen (N = 248) validiert. Basierend auf faktoranalytischen Ergebnissen wird die Adolescent Advertising Literacy Scale – Influencer Marketing (AALS-IM) vorgeschlagen. Diese Skala unterscheidet in ihrer finalen Fassung zwei Dimensionen der dispositionalen Kompetenz Advertising Literacy: Die konzeptuelle Dimension bezieht sich auf das Wissen über und das Erkennen von Influencer:innen-Marketing, während die evaluative Dimension die persönliche Haltung gegenüber Influencer:innen-Marketing darstellt. Beide Dimensionen werden im Instrument durch acht Skalen abgebildet, die sich aus insgesamt 41 Items zusammensetzen. Eine anwendungsbezogene Dimension, wie sie in der theoretischen Herleitung angenommen wurde, konnte in der empirischen Untersuchung nicht bestätigt werden. Die Betrachtung deskriptiver Statistiken und Schätzungen der internen Konsistenz sowie die Analyse korrelativer Zusammenhänge zwischen und innerhalb der Dimensionen ergänzen die Validierung. Ansätze für weiterführende Untersuchungen von Advertising Literacy im Kontext des Influencer:innen-Marketings werden abschliessend diskutiert., Advertising by influencers poses a challenge for young people, as the editorial content of a medium (without the intention to sell) is intertwined with the persuasive content of advertising messages (encouragement to consume). The aim of this article is therefore to develop an instrument that measures the competence of young people in dealing with influencer marketing. This is why existing scales on advertising literacy were translated, adapted to the context of influencer marketing and expanded. The resulting items were validated using a sample of 14- to 18-year-olds (N = 248). Based on factor-analytical results, the Adolescent Advertising Literacy Scale – Influencer Marketing (AALS-IM) is proposed. In its final version, it distinguishes between two dimensions of this dispositional competence: The conceptual dimension refers to knowledge about and recognition of influencer marketing, while the evaluative dimension represents the personal attitude towards influencer marketing. Both dimensions are represented in the instrument by a total of eight scales consisting of 41 items. The analysis of correlative relationships between and within the dimensions as well as the consideration of descriptive statistics and estimates of internal consistency complete the validation. To conclude, approaches for further studies of advertising literacy in the context of influencer marketing are discussed.

HfO₂ is one of the most common memristive materials and it is widely accepted that oxygen vacancies are prerequisite to reduce the forming voltage of the respective memristive devices. Here, a series of six oxygen engineered substoichiometric HfO₂₋ₓ thin films with varying oxygen deficiency is investigated by conductive atomic force microscopy (c‐AFM) and the switching process of substoichiometric films is observed on the nanoscale. X‐ray diffractometry (XRD) exhibits a phase transition from stoichiometric, monoclinic HfO₂ toward oxygen deficient, rhombohedral HfO₁.₇. The conductance of HfO₂₋ₓ is increasing with increasing oxygen deficiency, which is consistent with the increasing prevalence of the highly conductive rhombohedral phase. Simultaneously, c‐AFM reveals significant local conductivity differences between grains and grain boundaries, regardless of the level of oxygen deficiency. Single grains of highly oxygen deficient samples are formed at significant lower voltages. The mean forming voltage is reduced from (7.0 ± 0.6) V for HfO₂ to (1.9 ± 0.8) V for HfO₁.₇. Resistive switching on the nanoscale is established for single grains for the highest deficient thin film samples. The final resistance state is thereby dependent on the initial conductivity of the grains. These studies offer valuable insights into the switching behavior of memristive polycrystalline HfO₂.

Memory technologies are ubiquitous in our everyday life and the number of electronic devices relying on them keeps increasing rapidly. In established memories such as static random-access memory (SRAM), dynamic random-access memory (DRAM) and flash memory, further downscaling of transistors has slowed down leading to deviations from Moore’s law. However, this was so far considered a fundamental step towards ever increasing data storage, reduced energy consumption and lowered fabrication cost for decades. Furthermore, new applications such as image recognition or autonomous driving, which implement artificial neural networks, represent a challenge for the classic computer architecture. These challenges are the driving force for the development of new technologies such as emerging memories, including phase-change-based resistive, redox-based resistive and ferroelectric memories. Those memory types store information using different physical concepts than the established, mainly directly charge-based technologies. One important concept can be summarized under the term “memristor” or “memristive system”. It is based on a resistance change of a memory cell triggered by electric stimuli, which is dependent on the history of the memory material. The resistance in phase-change memories relies on the reversible transition of a phase-change material such as Ge2Sb2Te5 from an amorphous to a crystalline state. In contrast, the resistance in filamentary redox-based systems dependents on ion-migration and the formation/control of a conductive filament in a thin dielectric layer such as HfO2. This allows the achievement of at least two distinguishable memory states, which are repeatably accessible by applying voltage/current stimuli in a switching process. In ferroelectric memories, the data storage is based on the control of the electric polarization of a ferroelectric material such as doped HfO2. Due to their good scalability, non-volatility and fast as well as energy-efficient o

Resistive random‐access memories are promising candidates for novel computer architectures such as in‐memory computing, multilevel data storage, and neuromorphics. Their working principle is based on electrically stimulated materials changes that allow access to two (digital), multiple (multilevel), or quasi‐continuous (analog) resistive states. However, the stochastic nature of forming and switching the conductive pathway involves complex atomistic defect configurations resulting in considerable variability. This paper reveals that the intricate interplay of 0D and 2D defects can be engineered to achieve reproducible and controlled low‐voltage formation of conducting filaments. The author find that the orientation of grain boundaries in polycrystalline HfOₓ is directly related to the required forming voltage of the conducting filaments, unravelling a neglected origin of variability. Based on the realistic atomic structure of grain boundaries obtained from ultra‐high resolution imaging combined with first‐principles calculations including local strain, this paper shows how oxygen vacancy segregation energies and the associated electronic states in the vicinity of the Fermi level govern the formation of conductive pathways in memristive devices. These findings are applicable to non‐amorphous valence change filamentary type memristive device. The results demonstrate that a fundamental atomistic understanding of defect chemistry is pivotal to design memristors as key element of future electronics.

The familiarity principle posits that acceptance increases with exposure, which has previously been shown with in vivo and simulated experiences with connected and autonomous vehicles (CAVs). We investigate the impact of a simulated video-based first-person drive on CAV acceptance, as well as the impact of information customization, with a particular focus on acceptance by older individuals and those with lower education. Findings from an online experiment with N=799 German residents reveal that the simulated experience improved acceptance across response variables such as intention to use and ease of use, particularly among older individuals. However, the opportunity to customize navigation information decreased acceptance of older individuals and those with university degrees and increased acceptance for younger individuals and those with lower educational levels.