Unexpected precipitates in conjunction with layer-by-layer growth in Mn-enriched La2/3Sr1/3MnO3 thin films

THIN SOLID FILMS

卷:735

Article

Steffen, Alexandra^1,2  Glavic, Artur³  Gutberlet, Thomas⁴  Ambaye, Haile²  Schubert, Juergen^5,6  Gepraegs, Stephan⁷  Barthel, Juri⁸  Mattauch, Stefan¹  Zander, Willi^5,6  Kruth, Maximilian⁸  Schoeffmann, Patrick¹  Puetter, Sabine¹  Brueckel, Thomas⁴ 

[1] Forschungszentrum Julich, Heinz Maier Leibnitz Zentrum MLZ, Julich Ctr Neutron Sci JCNS, D-85748 Garching, Germany

[2] Oak Ridge Natl Lab, Neutron Sci Directorate, POB 2009, Oak Ridge, TN 37831 USA

[3] Paul Scherrer Inst, Lab Neutron & Muon Instrumentat, CH-5232 Villigen, Switzerland

[4] Forschungszentrum Julich, JCNS 2, D-52425 Julich, Germany

[5] Forschungszentrum Julich, PGI 9, D-52425 Julich, Germany

[6] Forschungszentrum Julich, JARAFIT, D-52425 Julich, Germany

[7] Bayer Akad Wissensch, Walther Meissner Inst, D-85748 Garching, Germany

[8] Forschungszentrum Julich, ER C 2, D-52425 Julich, Germany

关键词: Thin film;    Nanoscale structure;    Oxides;    Precipitation;    Lanthanum strontium manganate;    Molecular beam epitaxy;    Polarized neutron reflectometry;   

DOI  :  10.1016/j.tsf.2021.138862

来源: Elsevier

【 摘 要 】

In recent years, layer-by-layer heteroepitaxy has become a versatile tool for depositing novel materials not accessible in bulk form. While it is possible to control the mono layer sequence on an atomic scale with the help of sophisticated analysis techniques, not all important features of the thin film growth are detectable. We report on a detailed analysis of layer-by-layer deposited Mn-enriched La2/3Sr1/3MnO3 thin films using various, complementary experimental techniques. Our results show that, contrary to the expectations from the growth parameters and initial characterization, the films did not grow as atomic planes but segregated into layers of La2/3Sr1/3MnO3 with additional embedded precipitant crystals. We attribute this separation to a Volmer-Weber island-like growth of Mn3O4 crystals within layers of La2/3Sr1/3MnO3 due to increased surface tension inhibiting La and Sr oxides from sticking to nucleated Mn3O4 surfaces during the growth at high temperatures.

【 授权许可】

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