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arXiv · 2406.11763

Photoinduced Patterning of Oxygen Vacancies to Promote the Ferroelectric Phase of $\mathrm{Hf_{0.5}Zr_{0.5}O_2}$

Thomas E Beechem·Fernando Vega·Samantha T. Jaszewski·Benjamin L. Aronson·Kyle P. Kelley·Jon F. Ihlefeld
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Abstract

Photoinduced reductions in the oxygen vacancy concentration were leveraged to increase the ferroelectric phase fraction of $\mathrm{Hf_{0.5}Zr_{0.5}O_2}$ (HZO) thin-films. Modest ($\sim 0.02-0.77~\mathrm{mJ/\mu m^2}$) laser doses of visible light (488 nm, 2.54 eV) spatially patterned the concentration of oxygen vacancies as monitored by photoluminescence imaging. Local, tip-based, near-field, nanoFTIR measurements showed that the photoinduced oxygen vacancy concentration reduction promoted formation of the ferroelectric phase (space group $Pca2_1$) resulting in an increase in the piezoelectric response measured by piezoresponse force microscopy. Photoinduced vacancy tailoring provides, therefore, a spatially prescriptive, post-synthesis, and low-entry method to modify phase in \hfo-based materials.

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Thomas E Beechem, Fernando Vega, Samantha T. Jaszewski, Benjamin L. Aronson, Kyle P. Kelley, Jon F. Ihlefeld. 2024-06-17. Photoinduced Patterning of Oxygen Vacancies to Promote the Ferroelectric Phase of $\mathrm{Hf_{0.5}Zr_{0.5}O_2}$. https://doi.org/10.1063/5.0186481

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