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.

A novel flexible transparent electrode (TE) having a trilayer-stacked geometry and high optoelectronic performance and operational stability was fabricated by the spin coating method. The trilayer was composed of an ultrathin graphene (Gr) film sandwiched between a transparent and colorless polyimide (TCPI) layer and a m e t h a n e s u l f o n i c a c i d ( M S A ) -t r e a t e d p o l y ( 3 , 4ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) layer containing dimethylsulfoxide and Zonyl fluorosurfactant (designated as MSA-PDZ film). The introduction of solution-processable TCPI enabled the direct formation of high-quality graphene on organic surfaces with a clean interface. Stable doping of graphene with the MSA-PDZ film enabled tuning of the inherent work function and optoelectronic properties of the PEDOT:PSS films, leading to a high figure of merit of ∼70 in the as-fabricated TEs. Particularly, from multivariate and repetitive harsh environmental tests (T = −50 to 90 °C, over 90 RH%), the TCPI/Gr heterostructure exhibited excellent tolerance to mechanical and thermal stresses and gas barrier properties that protected the MSA-PDZ film from exposure to moisture. Owing to the synergetic effect from the TCPI/Gr/MSA-PDZ anode structure, the TCPI/Gr/MSA-PDZ-based polymer light-emitting diodes showed highly improved current and power efficiencies with maxima as high as 20.84 cd/A and 22.92 lm/W, respectively (comparable to those of indium tin oxide based PLEDs), in addition to much enhanced mechanical flexibility.

Silver nanowires (AgNWs) with high aspect ratio were obtained utilizing a tapered tubular reactor by the polyol process. The tapered tubular type flow reactor allowed us to obtain nanowires in high yield without defects that is generally encountered in a closed reactor due to excessive shearing for a long time. After reaction the AgNWs were precipitated in the aqueous solution with the aid of a hydrogen bond breaker and were recovered effectively without using a high-cost centrifugation process. Dispersion of the AgNWs were used to prepare transparent conducting electrode (TCE) films by a spray coating method, which showed 86% transmittance and 90 Ωsq´1 sheet resistance.

Engineering the electron dispersion of graphene to be spin-dependent is crucial for the realization of spin-based logic devices. Enhancing spin-orbit coupling in graphene can induce spin Hall effect, which can be adapted to generate or detect a spin current without a ferromagnet. Recently, both chemically and physically decorated graphenes have shown to exhibit large nonlocal resistance via the spin Hall and its inverse effects. However, these nonlocal transport results have raised critical debates due to the absence of field dependent Hanle curve in subsequent studies. Here, we introduce Au clusters on graphene to enhance spin-orbit coupling and employ a nonlocal geometry to study the spin Hall induced nonlocal resistance. Our results show that the nonlocal resistance highly depends on the applied gate voltage due to various current channels. However, the spin Hall induced nonlocal resistance becomes dominant at a particular carrier concentration, which is further confirmed through Hanle curves. The obtained spin Hall angle is as high as ∼0.09 at 2 K. Temperature dependence of spin relaxation time is governed by the symmetry of spin-orbit coupling, which also depends on the gate voltage: asymmetric near the charge neutral point and symmetric at high carrier concentration. These results inspire an effective method for generating spin currents in graphene and provide important insights for the spin Hall effect as well as the symmetry of spin scattering in physically decorated graphene.

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