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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 40: 2D Materials V: Growth, Structure and Substrate Interaction (joint session O/CPP)
CPP 40.1: Talk
Wednesday, March 29, 2023, 15:00–15:15, GER 37
Te on Pt(111): Structure and Growth of Surface Tellurides and PtxTey Films — Tilman Kißlinger, Alexandra Schewski, Andreas Raabgrund, Hannah Loh, Lutz Hammer, and •M. Alexander Schneider — Lehrstuhl für Festkörperphysik, FAU Erlangen-Nürnberg, Staudtstr. 7, 91058 Erlangen
By LEED-IV, STM and DFT we investigated the tellurization of Pt(111) in UHV. For Te coverages Θ < 0.5 ML surface tellurides are formed. In this coverage regime and after thermal annealing, we find only two well ordered surface telluride structures with (3 × 3) and (10 × 10) periodicity, the former was mistaken for a defective PtTe2 film [1]. Our LEED-IV structure analyses determine the atomic structure and show that the Pt(111) surface undergoes massive reconstructions upon reaction with Te.
For Θ > 0.5 ML, compact islands develop which eventually coalesce to a complete platinum telluride layer. Again by LEED-IV analyses we find that the first layer is a Pt2Te2 layer on which as second layer a PtTe2 film can be grown. Both form an overlayer where 7 × 7 film unit cells lie on 10 × 10 Pt(111) unit cells. Furthermore, we find that the interface to the Pt(111) bulk still contains the ≈ 0.5 ML Te originally bound in the (10 × 10) superstructure. Electronic properties of the films determined by STS and implications for the MBE growth of transition metal dichalcogenides by surface tellurization will be discussed.
[1] L. Liu, D. Zemlyanov, and Y.P. Chen, 2D Mater. 8, 045033 (2021)