van der Waals (vdW) layered materials have provided novel opportunities to explore interesting physical properties such as thickness-dependent bandgap, moiréexcitons, superconductivity, and superfluidity. However, the presence of interlayer resistance along the thickness and Schottky barrier in metal-to-2D vdW semiconducting materials causes a limited interlayer charge injection efficiency, perturbing various intrinsic properties of 2D vdW multilayers. Herein, we report a simple but powerful contact electrode design to enhance interlayer carrier injection efficiency along the thickness by constructing vertical double-side contact (VDC) electrodes. A 2-fold extended contact area of VDC not only strongly limits an interlayer resistance contribution to the field-effect mobility and current density at the metal-to-2D semiconductor interface but also significantly suppresses both current transfer length (≤1 μm) and specific contact resistivity (≤1 mΩ•cm 2 ), manifesting clear benefits of VDC in comparison with those in conventional top-contact and bottom-contact configurations. Our layout for contact electrode configuration may suggest an advanced electronic device platform for high-performing 2D optoelectronic devices.

Electrical conductivity (σ) indicates the efficiency of current flow through electronic materials, and varies with both carrier density (n 2D ) and mobility (𝜇). Studying the temperature-dependent σ of a material allows for the elucidation of various carrier transport mechanisms such as metal-insulator phase transition, Coulomb impurity scattering, metal-semiconductor barrier, and quantum tunneling features. Herein, we report a considerable interlayer resistance (R IT ) effects on the carrier scattering mechanism occurring in a multilayer rhenium disulfide (ReS 2 ) transistor, particularly at high temperatures. At room temperature (T = 300 K), a channel centroid gradually migrates from the bottom to the top surface of ReS 2 multilayers by contributing to the suppressed R IT with increasing electrostatic drain (V D ) and gate (V G ) bias conditions. Meanwhile, for temperatures above 380 K, the effective interlayer resistance quickly decreases with increasing V G , and the ReS 2 multilayer consequently demonstrates an anomalous carrier mobility enhancement. For a better insight into the charge scattering mechanism, the obtained temperature-dependent carrier mobility was further analyzed by employing Matthiessen's rule for Coulomb impurity scattering, phonon scattering, and interlayer resistance scattering, respectively. Our study would shed light on deep understanding for the high temperature carrier scattering mechanism and further improvements in diverse optoelectronic applications of ReS 2 multilayers.