First-Principles-Based Multiphysics Modeling and Simulation of On-Chip Cu-Graphene Hybrid Nanointerconnects in Comparison With Simplified Model-Based Analysis

Cu-Graphene (Cu-G) hybrid nanointerconnects, as well as many graphene-based devices, have a potential to significantly advance the technology of on-chip integrated circuits (IC). However, their modeling and simulation for a long time has relied on simplified steady-state models of graphene. To examine the validity and accuracy of existing simplified models in high-frequency and subnanometer applications, in this article, we theoretically analyze the assumptions made in existing simplified models. Meanwhile, we develop a first-principles-based multiphysics modeling and simulation algorithm to numerically assess the accuracy of the simplified model-based analysis of Cu-G interconnects. In this algorithm, the Maxwell's equations, the equation characterizing graphene, and the Boltzmann equation are cosimulated in time domain. A significant difference is observed between the first-principles-based analysis and the simplified model-based one when the frequency is high or/and the dimension of the Cu-G structure is small, which necessitates the first-principles-based multiphysics modeling and simulation for the design of advanced Cu-G interconnects.