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Low-dimensional materials hold great promises for exploring emergent physical phenomena, nanoelectronics, and quantum technologies. Their synthesis often depends on catalytic metal films, from which the synthesized materials must be transferred to insulating substrates to enable device functionality and minimize interfacial interactions during quantum investigations. Conventional transfer methods, such as chemical etching or electrochemical delamination, degrade material quality, limit scalability, or prove incompatible with complex device architectures. Here, a scalable, etch-free transfer technique is presented, employing Field's metal (51% In, 32.5% Bi, and 16.5% Sn by weight) as a low-melting-point mechanical support to gently delaminate low-dimensional materials from metal films without causing damage. Anchoring the metal film during separation prevents tearing and preserves material integrity. As a proof of concept, atomically precise graphene nanoribbons (GNRs) are transferred from Au(111)/mica to dielectric substrates, including silicon dioxide (SiO_2) and single-crystalline lanthanum oxychloride (LaOCl). Comprehensive characterization confirms the preservation of structural and chemical integrity throughout the transfer process. Wafer-scale compatibility and device integration are demonstrated by fabricating GNR-based field-effect transistors (GNRFETs) that exhibit room-temperature switching with on/off current ratios exceeding 10^3. This method provides a scalable and versatile platform for integrating low-dimensional materials into advanced low-dimensional materials-based technologies. 

We investigated the formation of Schottky barriers at the interface between rare-earth tritelluride (RTe3) crystals and n-type silicon (n-Si) substrates. This study explores the rectifying characteristics of RTe3/n-Si junctions (R = Dy, Ho, Er) and their relation to the charge density wave (CDW) transition. Using the thermionic emission model, we analyzed current–voltage (I–V) measurements to obtain the Schottky barrier height (ϕSBH) and the ideality factor (η). The temperature dependence of the extracted ϕSBH and η reveals kink features near the CDW transition temperature. The Schottky–Mott model is employed to explain these kink features in the derivatives of ϕSBH and 1/η and attributes them to changes in the work function of RTe3 during the CDW transition. Our findings suggest that Schottky junctions can be utilized to probe the electronic states of RTe3, enabling potential RTe3 device applications in electronics and optoelectronics. 

Graphene nanoribbons (GNRs), when synthesized with atomic precision by bottom–up chemical approaches, possess tunable electronic structure, and high theoretical mobility, conductivity, and heat dissipation capabilities, which makes them an excellent candidate for channel material in post-silicon transistors. Despite their immense potential, achieving highly transparent contacts for efficient charge transport—which requires proper contact selection and a deep understanding of the complex one-dimensional GNR channel-three-dimensional metal contact interface—remains a challenge. In this study, we investigated the impact of different electron-beam deposited contact metals—the commonly used palladium (Pd) and softer metal indium (In)—on the structural properties and field-effect transistor performance of semiconducting nine-atom wide armchair GNRs. The performance and integrity of the GNR channel material were studied by means of a comprehensive Raman spectroscopy analysis, scanning tunneling microscopy (STM) imaging, optical absorption calculations, and transport measurements. We found that, compared to Pd, In contacts facilitate favorable Ohmic-like transport because of the reduction of interface defects, while the edge structure quality of GNR channel plays a more dominant role in determining the overall device performance. Our study provides a blueprint for improving device performance through contact engineering and material quality enhancements in emerging GNR-based technology.