Dresden 2014 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DS: Fachverband Dünne Schichten

DS 40: Focus Session: Resistive Switching by Redox and Phase Change Phenomena VII (Optical properties and theory of PC materials)

DS 40.6: Vortrag

Donnerstag, 3. April 2014, 12:45–13:00, CHE 89

Reducing the number of domain orientations of Sb₂Te₃ on Si(111) by surface engineering — •Jos Boschker¹, Jamo Momand², Bart Kooi², and Raffaella Calarco¹ — ¹Paul-Drude-Institut für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin, Germany — ²Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands

The epitaxy of interfacial phase change memory [1] requires a detailed understanding of the stacking of van der Waals solids (Sb₂Te₃) with 3-dimensional solids (GeTe). Here we use to growth of Sb₂Te₃ on Si(111) as a model system for studying this kind of epitaxy. We show that Sb₂Te₃ grown on Si(111)-(7x7) exhibits ten different domain orientations, even though only one is expected based on the symmetries of the two materials. We show that the in-plane rotations are due to the formation of a coincidence lattice between Sb₂Te₃ and the dangling bonds on the Si(111)-(7x7) surface. Furthermore, we demonstrate that the number of domain orientations can be reduced to two when Sb₂Te₃ is grown on Si(111)-(√3x√3)R30^∘-Sb or Si(111)-(1x1)-H. Finally, in-plane rotations of ultrathin Sb₂Te₃ layers on Si(111)-(7x7) and Si(111)-(√3x√3)R30^∘-Sb are determined using angular resolved RHEED. This detailed understanding of the epitaxy of Sb₂Te₃ on Si(111) is important for the growth of Sb₂Te₃/GeTe superlattices and thus for the optimization of interfacial phase change memory.

[1] R. E. Simpson, P. Fons, A. V. Kolobov, T. Fukaya, M. Krbal, T. Yagi, and J. Tominaga, Interfacial phase-change memory, Nat. Nanotechnol., vol. 6, pp. 501-5, Aug. 2011.