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This content will become publicly available on July 7, 2026

Title: Phase selection and texturing in molybdenum oxide films grown by reactive magnetron sputtering
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 α-MoO3 but also for controlling grain size and preferred orientation. Both mica and sapphire support exclusive MoO2 formation for 0.15 ≤ fO2 ≤ 0.25 at deposition temperatures Tdep = 400 and 500 °C, while α-MoO3 forms only at Tdep = 400 °C for 0.35 ≤ fO2 ≤ 0.5. Within the fO2 windows favoring each phase, high fO2 fosters large grains with out-of-plane 0k0 texture, except for MoO2 on c-sapphire at Tdep = 500 °C, where no fO2-texture correlation is discernible. These findings provide a framework for rational synthesis of single-phase monoclinic MoO2 and orthorhombic MoO3 with control over texture and microstructure to access desired properties.  more » « less
Award ID(s):
2135725
PAR ID:
10633520
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
Applied Physics Letters
Volume:
127
ISSN:
0003-6951
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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