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As the elements of integrated circuits are downsized to the nanoscale, the current Cu‐based interconnects are facing limitations due to increased resistivity and decreased current‐carrying capacity because of scaling. Here, the bottom‐up synthesis of single‐crystalline WTe2 nanobelts and low‐ and high‐field electrical characterization of nanoscale interconnect test structures in various ambient conditions are reported. Unlike exfoliated flakes obtained by the top‐down approach, the bottom‐up growth mode of WTe2 nanobelts allows systemic characterization of the electrical properties of WTe2 single crystals as a function of channel dimensions. Using a 1D heat transport model and a power law, it is determined that the breakdown of WTe2 devices under vacuum and with AlOx capping layer follows an ideal pattern for Joule heating, far from edge scattering. High‐field electrical measurements and self‐heating modeling demonstrate that the WTe2 nanobelts have a breakdown current density approaching ≈100 MA cm−2, remarkably higher than those of conventional metals and other transition‐metal chalcogenides, and sustain the highest electrical power per channel length (≈16.4 W cm−1) among the interconnect candidates. The results suggest superior robustness of WTe2 against high‐bias sweep and its possible applicability in future nanoelectronics.

The edge-to-edge connected metal-semiconductor junction (MSJ) for two-dimensional (2D) transistors has the potential to reduce the contact length while improving the performance of the devices. However, typical 2D materials are thermally and chemically unstable, which impedes the reproducible achievement of high-quality edge contacts. Here we present a scalable synthetic strategy to fabricate low-resistance edge contacts to atomic transistors using a thermally stable 2D metal, PtTe2. The use of PtTe2 as an epitaxial template enables the lateral growth of monolayer MoS2 to achieve a PtTe2-MoS2 MSJ with the thinnest possible, seamless atomic interface. The synthesized lateral heterojunction enables the reduced dimensions of Schottky barriers and enhanced carrier injection compared to counterparts composed of a vertical 3D metal contact. Furthermore, facile position-selected growth of PtTe2-MoS2 MSJ arrays using conventional lithography can facilitate the design of device layouts with high processability, while providing low contact resistivity and ultrashort transfer length on wafer scales.

Following the celebrated discovery of graphene, considerable attention has been directed toward the rich spectrum of properties offered by van der Waals crystals. However, studies have been largely limited to their 2D properties due to lack of 1D structures. Here, the growth of high-yield, single-crystalline 1D nanobelts composed of transition metal ditellurides at low temperatures (T ≤ 500 °C) and in short reaction times (t ≤ 10 min) via the use of tellurium-rich eutectic metal alloys is reported. The synthesized semimetallic 1D products are highly pure, stoichiometric, structurally uniform, and free of defects, resulting in high electrical performances. Furthermore, complete compositional tuning of the ternary ditelluride nanobelts is achieved with suppressed phase separation, applicable to the creation of unprecedented low-dimensional materials/devices. This approach may inspire new growth/fabrication strategies of 1D layered nanostructures, which may offer unique properties that are not available in other materials.