Regensburg 2025 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 44: Poster Oxides and Insulator Surfaces: Structure, Epitaxy and Growth
O 44.3: Poster
Tuesday, March 18, 2025, 18:00–20:00, P2
Pulsed laser deposition of epitaxial hematite α-Fe2O3 thin films on Al2O3(1102) — •Sarah Tobisch, Giada Franceschi, Michael Schmid, Gareth Parkinson, Ulrike Diebold, and Michele Riva — Institute of Applied Physics, TU Wien, Vienna, Austria
Hematite α-Fe2O3 is a widely used support material for catalysis due to its abundance and high stability at ambient pressures. However, the insulating nature of the material poses major challenges, as it makes it difficult to achieve sufficient conductivity for techniques such as scanning tunnelling microscopy (STM). Samples commonly consist of natural crystals that can contain a variety of impurities as well as structural defects. The former problem is hardly controllable while the latter can lead to mechanical instabilities. While the conductivity can be improved by growing Ti-doped epitaxial films, the synthesis of hematite single crystals is still in its infancy and the size of these crystals is insufficient for many surface-analysis techniques. Therefore, new strategies to ensure the growth of flat and atomically defined doped films without the need of natural-crystal substrates are highly desired.
In this work, epitaxial growth of Ti-doped Fe2O3 on Al2O3(1102) was investigated using a pulsed-laser-deposition (PLD) system with high-pressure reflection high-energy electron diffraction (RHEED) to optimize the growth conditions and monitor the growth behavior. The morphology and composition of the film’s surface was characterized using x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and STM.
Keywords: Epitaxy; PLD; Hematite; Surface Science