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arXiv · 1607.05955

Epitaxial growth of complex oxides on silicon by enhanced surface diffusion in large area pulsed laser deposition

Abstract

Homogeneous highly epitaxial LaSrMnO3 (LSMO) thin films have been grown on Yttria-stabilized-Zirconia (YsZ) / CeO2 buffer layers on technological relevant 4" silicon wafers using a Twente Solid State Technology B.V. (TSST) developed large area Pulsed Laser Deposition (PLD) setup. We study and show the results of the effect of an additional SrRuO3 buffer layer on the growth temperature dependent structural and magnetic properties of LSMO films. With the introduction of a thin SrRuO3 layer on top of the buffer stack, LSMO films show ferromagnetic behaviour for growth temperatures as low as 250C. We suggest that occurrence of epitaxial crystal growth of LSMO at these low growth temperatures can be understood by an improved surface diffusion, which ensures sufficient intermixing of surface species for formation of the correct phase. This intermixing is necessary because the full plume is collected on the 4" wafer resulting in a compositional varying flux of species on the wafer, in contrast to small scale experiments.

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Rik Groenen, Zhaoliang Liao, Nicolas Gauquelin, Roel Hoekstra, Bart Spanjer, Merle van Gorsel, Sam Borkent, Minh Nguyen, Laura Vargas-LLona, Eddy Rodijk, Cas Damen, Jo Verbeeck, Gertjan Koster, Guus Rijnders. 2016-07-20. Epitaxial growth of complex oxides on silicon by enhanced surface diffusion in large area pulsed laser deposition. https://arxiv.org/abs/1607.05955

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