Berlin 2015 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
DS: Fachverband Dünne Schichten
DS 37: Focussed Session: Oxide semiconductors II (joint session with HL)
DS 37.4: Vortrag
Donnerstag, 19. März 2015, 16:00–16:15, H 2032
Structural properties and phonon modes of (AlxGa1−x)2O3 — •Christian Kranert, Marcus Jenderka, Jörg Lenzner, Michael Lorenz, Holger von Wenckstern, Rüdiger Schmidt-Grund, and Marius Grundmann — Universität Leipzig, Institut für Experimentelle Physik II, Semiconductor Physics Group, Leipzig, Germany
We present a combined X-ray diffraction and Raman scattering study on a 2-inch diameter thin film with a continuous composition spread (CCS) [1] in comparison to bulk-like ceramic samples. For the composition range for which the ceramic materials exclusively exhibit the β-modification, we obtained their individual lattice parameters as a function of the composition. These comply with Vegard’s rule. We further investigated these samples by Raman spectroscopy. The obtained phonon energy dependencies on the composition in the β-phase are found to be linear as well.
The CCS approach for the thin films allows us to determine its properties for virtually any composition within the composition range of the sample. The comparison to the ceramic samples shows a reduced out-of-plane lattice parameter for the thin films. Despite that, the phonon energies show a good agreement to the bulk values.
The material β-Ga2O3 is of interest for deep UV optoelectronics. Alloying with Al2O3 increases its band gap, which makes the alloy (Al,Ga)2O3 suitable for an application in Ga2O3-based heterostructures or as barrier material for Ga2O3 quantum wells.
[1] H. von Wenckstern et al., CrystEngComm 15, 10020 (2013)