Surface phonon polaritons-using perpendicular electric fields monitoring in midinfrared circular antennas fabricated by atomic layer deposition method

Distribution of electric fields normal to the antenna plane in the depth direction was experimentally investigated by using mid-infrared circular antennas that were formed on Al₂O₃/SiO₂/Si and SiO₂/Al₂O₃/Si. The Al₂O₃ layer was deposited using an atomic layer deposition technique which allowed for layer thickness control with an accuracy of nanometers. The field distribution in the depth direction was estimated by observing the surface phonon polariton signals originating from the SiO₂ layer.