Electrical/dielectric properties of metal-oxide nanofilms via anodizing Al/Hf metal layers

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F18%3APU130663" target="_blank" >RIV/00216305:26620/18:PU130663 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Electrical/dielectric properties of metal-oxide nanofilms via anodizing Al/Hf metal layers

Popis výsledku v původním jazyce

Hafnium oxide (HfO2) is a high-temperature ceramic with excellent electrical, dielectric and optical properties, which may be substantially enhanced in the nanostructured material. Here, we have developed selforganized arrays of hafnium-oxide nanorods and examined their properties by electrochemical impedance spectroscopy (EIS). For sample preparation, Al/Hf layers are magnetron sputtered onto SiO2/Si substrates, anodized and then re-anodized to a more anodic potential. This results in the growth of a porous alumina film, followed by pore-assisted oxidation of the Hf underlayer. The films consist of discrete HfOx protrusions, penetrating the alumina pores and anchored to a uniform oxide layer that forms under the pores. Postanodizing treatments include annealing at 600°C in air or vacuum and selective dissolution of the alumina overlayer. The electrical/dielectric behavior of the hafnium oxide nanorod arrays, embedded in or free from alumina, was EIS-investigated in a borate buffer solution. In the re-anodized (not annealed) state the bottom oxide layer behaves as a good dielectric whereas the nanorods are semiconducting in nature. This situation does not change substantially by the annealing in air, still resulting in a dielectric bottom layer and semiconducting nanorods. However, after the annealing in vacuum, the whole film becomes an n-type semiconductor. Further investigation is in progress to understand the formation-structure-morphology relationship, aiming at exploring the functional properties of the films.

Název v anglickém jazyce

Electrical/dielectric properties of metal-oxide nanofilms via anodizing Al/Hf metal layers

Popis výsledku anglicky

Hafnium oxide (HfO2) is a high-temperature ceramic with excellent electrical, dielectric and optical properties, which may be substantially enhanced in the nanostructured material. Here, we have developed selforganized arrays of hafnium-oxide nanorods and examined their properties by electrochemical impedance spectroscopy (EIS). For sample preparation, Al/Hf layers are magnetron sputtered onto SiO2/Si substrates, anodized and then re-anodized to a more anodic potential. This results in the growth of a porous alumina film, followed by pore-assisted oxidation of the Hf underlayer. The films consist of discrete HfOx protrusions, penetrating the alumina pores and anchored to a uniform oxide layer that forms under the pores. Postanodizing treatments include annealing at 600°C in air or vacuum and selective dissolution of the alumina overlayer. The electrical/dielectric behavior of the hafnium oxide nanorod arrays, embedded in or free from alumina, was EIS-investigated in a borate buffer solution. In the re-anodized (not annealed) state the bottom oxide layer behaves as a good dielectric whereas the nanorods are semiconducting in nature. This situation does not change substantially by the annealing in air, still resulting in a dielectric bottom layer and semiconducting nanorods. However, after the annealing in vacuum, the whole film becomes an n-type semiconductor. Further investigation is in progress to understand the formation-structure-morphology relationship, aiming at exploring the functional properties of the films.

Druh

D - Stať ve sborníku

CEP obor

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OECD FORD obor

10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

Projekt

<a href="/cs/project/GA17-13732S" target="_blank" >GA17-13732S: Multifunkční pole nanodrátků z elektrokeramických materiálů na bázi HfO2 a ZrO2 vysoce uspořádaných na substrátu (ZiHaN)</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Conference Proceedings of 9th International Conference on Nanomaterials - Research & Application (Nanocon 2017)

ISBN

978-80-87294-81-9

ISSN

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e-ISSN

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Počet stran výsledku

6

Strana od-do

51-56

Název nakladatele

TANGER Ltd.

Místo vydání

Ostrava, Czech Republic

Místo konání akce

Brno

Datum konání akce

18. 10. 2017

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000452823300007