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Abstract We report on the structure and dielectric properties of ternary A6B2O17(A = Zr; B = Nb, Ta) thin films and ceramics. Thin films are produced via sputter deposition from dense, phase‐homogenous bulk ceramic targets, which are synthesized through a reactive sintering process at 1500°C. Crystal structure, microstructure, chemistry, and dielectric properties are characterized by X‐ray diffraction and reflectivity, atomic force microscopy, X‐ray photoelectron spectroscopy, and capacitance analysis, respectively. We observe relative permittivities approaching 60 and loss tangents <1 × 10−2across the 103–105 Hz frequency range in the Zr6Nb2O17and Zr6Ta2O17phases. These observations create an opportunity space for this novel class of disordered oxide electroceramics.
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Temperature-dependent dielectric behavior of A 6 B 2O17 ( A = Zr, Hf; B = Nb, Ta) phases
We report on temperature-dependent dielectric behavior of disordered ternary A6B2O17 (A = Zr, Hf; B = Nb, Ta)-form oxides in the GHz frequency range. The microwave dielectric properties including relative permittivity, dielectric loss, and temperature-dependent relative permittivity were characterized using cylindrical dielectric resonators using a resonant post measurement technique. Dielectric measurements through the resonant post method approach generally agree with dielectric measurements of A6B2O17 bulk ceramics measured through standard resonant post techniques. Coefficients describing the temperature-dependent relative permittivity for ternary A6B2O17 phases are strongly positive, suggesting contributions to polarizability arising from long-range mechanisms potentially associated with structural disorder. These observations support the working hypothesis that material functionality can be engineered by the chemical diversity and structural disorder possible in high configurational entropy A6B2O17 phases.
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- Award ID(s):
- 2011839
- PAR ID:
- 10541041
- Publisher / Repository:
- American Institute of Physics Publishing
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 125
- Issue:
- 9
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0219964
