Edge-Oxidized Germanene Nanoribbons for Nanoscale Metal Interconnect Applications

Abstract

Role of elemental oxygen atom as a terminating element on the electronic and transport properties of germanene nanoribbons (GeNRs) has been investigated using the density functional theory and nonequilibrium Green’s function approach. In principle, we have considered all possible stable combinations of oxygen and hydrogen terminations for both zigzag as well as armchair edge states. Our binding energy ( ${E}_{b}$ ) calculations depict that oxygen termination leads to thermodynamically stable configurations with enhanced stability for the enhanced O-atom concentration. Furthermore, dispersion relation ( E-k structures) and density-of-states profile calculations suggest that oxygen-terminated GeNR is mostly metallic in nature or possesses a very narrow bandgap. On the account of such enhanced metallicity, we have proposed these structures for metal interconnects application. To gauge their performance as metal interconnect, we have calculated crucial parameters, such as ${R}_{Q}, {L}_{k}$ , and ${C}_{Q}$ , using the standard two-probe setup. With the least calculated values of kinetic inductance ( ${L}_{k}=\text {4.14}\,\,\text {nH}/\mu \text {m}$ ) and quantum capacitance ( ${C}_{Q}=\text {8.89}\,\,\text {pF}/\text {cm}$ ), zigzag GeNR with both edge-oxidized (O-ZGeNR-O) configurations can be considered as the potential candidate for nanoscale interconnect application.