Transition Metal Dichalcogenides as Nanoscale 2D Interconnects: Performance Analysis of MoTe2, TaS2, WTe2, NbSe2, and TaSe2 Nanoribbons

This study evaluates the potential of transition metal dichalcogenide (TMD) nanoribbons, specifically MoTe₂, TaS₂, WTe₂, NbSe₂, and TaSe₂ as nanoscale interconnects to address scaling challenges in semiconductor technology. Six configurations, 1T′ MoTe₂, 1T TaS₂, 1T′ WTe₂, 1T NbSe₂, and 2H TaSe₂ (in both armchair and zigzag orientations), are assessed in terms of key performance metrics such as propagation delay, crosstalk-induced delay, noise performance, energy-delay product (EDP), stability, and frequency response. To ensure a comprehensive analysis of structural variations, three distinct edge termination configurations have been investigated for each of the TMD (MX₂) materials: C1, with both edges terminated by metal (M) atoms; C2, with one edge terminated by a M atom and the other by a chalcogen (X) atom; and C3, with both edges terminated by X atoms. Interconnect behavior is simulated using a π-type equivalent single conductor (ESC) model in conjunction with a driver-interconnect-load (DIL) setup. The ESC circuit parameters, derived from the number of conducting channels and Fermi velocity calculated via first-principles simulations, facilitated detailed delay and noise calculations, while the open-loop transfer function provided insights into frequency response, Nyquist plots, and damping factors. In addition to our six proposed configurations (each with three distinct edge configurations), nine configurations reported in the literature are compared in terms of the same performance parameters, thereby evaluating a total of twenty-seven configurations. Among these, TaS₂ nanoribbon-based configurations outperformed the others overall, with MoTe₂, WTe₂, and NbSe₂ also showing competitive performance; TaSe₂ configurations, despite their poorer interconnect performance, demonstrated superior stability. These findings indicate that TaS₂, along with NbSe₂, WTe₂, and MoTe₂, is a promising candidate for future nanoscale interconnect applications at reduced dimensions.