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arXiv · 2502.10589

Phase selection and texturing in molybdenum oxide films grown by reactive magnetron sputtering

Faezeh A. F. Lahiji·Biplab Paul·Grzegorz Greczynski·Ganpati Ramanath·Arnaud le Febvrier·Per Eklund
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Abstract

Molybdenum oxide films offer a rich variety of properties for diverse applications, but exclusive synthesis of desired phases is a major challenge. Here, we demonstrate that oxygen flow ratio fO2 = [O2]/[Ar+O2] is crucial not only for phase selection of non-layered monoclinic MoO2 and layered orthorhombic alpha-MoO3 but also for controlling grain size and preferred orientation. Both mica and sapphire support exclusive MoO2 formation in the 0.15 < fO2 < 0.25 window at deposition temperatures Tdep = 400 and 500 degree C and alpha-MoO3 formation in the 0.35 < fO2 < 0.5 window at 400 degree C. Within fO2 windows favoring exclusive phase formation, high fO2 fosters large grains with out-of-plane 0k0 texture, except for MoO2 films on c-sapphire that show no systematic trends. These findings provide a framework for rational synthesis of phase-pure monoclinic MoO2 and orthorhombic MoO3 with control over texture and microstructure to access desired properties.

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Faezeh A. F. Lahiji, Biplab Paul, Grzegorz Greczynski, Ganpati Ramanath, Arnaud le Febvrier, Per Eklund. 2025-02-14. Phase selection and texturing in molybdenum oxide films grown by reactive magnetron sputtering. https://arxiv.org/abs/2502.10589

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