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Imaging of Microwave Permittivity, Tunability, and Damage Recovery in (Ba,Sr)TiO3 Thin Films

D. E. Steinhauer·C. P. Vlahacos·C. Canedy·A. Stanishevsky·J. Melngailis·R. Ramesh·F. C. Wellstood·Steven M. Anlage
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Abstract

We describe the use of a near-field scanning microwave microscope to quantitatively image the dielectric permittivity and tunability of thin-film dielectric samples on a length scale of 1 micron. We demonstrate this technique with permittivity images and local hysteresis loops of a 370 nm thick barium strontium titanate thin film at 7.2 GHz. We also observe the role of annealing in the recovery of dielectric tunability in a damaged region of the thin film. We can measure changes in relative permittivity as small as 2 at 500, and changes in dielectric tunability as small as 0.03 V$^{-1}$.

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D. E. Steinhauer, C. P. Vlahacos, C. Canedy, A. Stanishevsky, J. Melngailis, R. Ramesh, F. C. Wellstood, Steven M. Anlage. 1999-10-01. Imaging of Microwave Permittivity, Tunability, and Damage Recovery in (Ba,Sr)TiO3 Thin Films. https://doi.org/10.1063/1.125270

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