Atomically Thin Metal–Dielectric Heterostructures by Atomic Layer Deposition

• DOI: 10.1021/acsami.2c22590
• Publication Date: 2023-04-25T15:48:53Z
• Authors: Pallabi Paul; Paul Schmitt; Vilborg Vala Sigu...; Kevin Hanemann; Nadja Felde; Sven Schröder; Felix Otto; Marco Gruenewald; Torsten Fritz; Vladimir Roddatis; Andreas Tünnermann; Adriana Szeghalmi
• Keywords: Ellipsometry; X-ray reflectivity

Heterostructures increasingly attracted attention over the past several years to enable various optoelectronic and photonic applications. In this work, atomically thin interfaces of Ir/Al2O3 heterostructures compatible with micro-optoelectronic technologies are reported. Their structural optical properties were determined by spectroscopic microscopic techniques (XRR, XPS, HRTEM, ellipsometry, UV/vis/NIR spectrophotometry). The XRR HRTEM analyses reveal a layer-by-layer growth mechanism Ir in atomic scale heterostructures, which is different from typical island-type metals on dielectrics. Alongside, XPS investigations imply formation Ir-O-Al bonding at for lower concentrations, contrast nanoparticle core-shell structure formation. Precisely tuning ratio constituents ensures control dispersion profile along transition effective dielectric metallic heterostructures. coating thickness was varied ranging few angstroms films about 7 nm has been observed structures containing individual thicknesses 2-4 nm. Following this, we show epsilon-near-zero metamaterials tunable constants precisely varying composition such Overall, comprehensive study metal-dielectric addressed, indicating an extension material portfolio available novel functionalities.