Abstract
Polar ZnO single crystals were microstructured in a controlled fashion by electrochemical etching. Surfaces with pyramids and inversed pyramids on oxygen and zinc faces, respectively, were received. Photoluminescence spectra of bulk and anodized ZnO samples were investigated at room and low temperatures. Cathodoluminescence images were also recorded from areas with different structures. A significant enhancement of light emission of the prepared microstructures was achieved after anodization. This allows to use such microstructures in light emitting devices and solar cells.
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ACKNOWLEDGMENTS
Victor Zalamai and Eduard Monaico express their thanks to the Alexander von Humboldt Foundation for support.
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V. Zalamai, Ed. Monaico and G. Colibaba designed the experiments; G. Colibaba synthesized the samples. Ed. Monaico and El. Monaico performed electrochemical etching and surface morphology characterization. V. Zalamai carried out photoluminescence measurements. V. Zalamai, Ed. Monaico and G. Colibaba contributed to manuscript preparation. All authors participated in the discussions. All authors have given approval to the final version of the manuscript.
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The authors acknowledge financial support from the National Agency for Research and Development, Moldova, under State Programme Project nos. 20.80009.5007.20 and 20.80009.5007.16.
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Zalamai, V.V., Colibaba, G.V., Monaico, E.I. et al. Enhanced Emission Properties of Anodized Polar ZnO Crystals. Surf. Engin. Appl.Electrochem. 57, 117–123 (2021). https://doi.org/10.3103/S1068375521010166
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DOI: https://doi.org/10.3103/S1068375521010166