Fabrication and Optical Characterization of CMOS‐Compatible Honeycomb‐Like Large‐Scale Lattices of Near‐Field Coupled Plasmonic TiN Nanotriangles

Abstract Honeycomb‐like plasmonic titanium nitride nanotriangle arrays defined by photolithography and fabricated in a modified silicon‐germanium electronic–photonic integrated circuit process in a state‐of‐the‐art pilot line. The nanotriangle arrays are characterized in experiments and simulations. The momentum‐dependent reflectance spectra exhibit not only features that are consistent with surface lattice resonances in the honeycomb lattice but also minima governed by near‐field coupling of the individual nanotriangles. The optical characterization results in combination with simulation‐based predictions indicate that such nanotriangle arrays are capable of supporting collective plasmonic resonances that can be described as massless Dirac particles. The fabrication approach opens up the possibility of integrating the structures into device fabrication processes, and avenues toward near‐infrared sensing and communication applications are predicted.