We report on the dielectric response of epitaxial BaSnO3 films grown on Nb-doped SrTiO3 (001) substrates using a hybrid molecular beam epitaxy approach. Metal-insulator-metal capacitors were fabricated to obtain frequency- and temperature-dependent dielectric constant and loss. Irrespective of film thickness and cation stoichiometry, the dielectric constant obtained from Ba1−xSn1−yO3 films remained largely unchanged at 15-17 and was independent of frequency and temperature. A loss tangent of ∼1 × 10−3 at 1 kHz < f < 100 kHz was obtained for stoichiometric films, which increased significantly with non-stoichiometry. Using density functional theory calculations, these results are discussed in the context of point defect complexes that can form during film synthesis.
Nunn, W., Prakash, A., Bhowmik, A., Haislmaier, R., Yue, J., García Lastra, J. M., & Jalan, B. (2018). Frequency- and temperature-dependent dielectric response in hybrid molecular beam epitaxy-grown BaSnO3 films. A P L Materials, 6(6), . https://doi.org/10.1063/1.5027567