PLD Epitaxial Thin‐Film BaTiO3 on MgO − Dielectric and Electro‐Optic Properties

oleh: Joel Winiger, Killian Keller, David Moor, Michael Baumann, Donghoon Kim, Daniel Chelladurai, Manuel Kohli, Tobias Blatter, Eric Dénervaud, Yuriy Fedoryshyn, Ueli Koch, Salvador Pané, Rachel Grange, Juerg Leuthold

Format: Article
Diterbitkan: Wiley-VCH 2024-01-01

Deskripsi

Abstract The study demonstrates high‐quality pulsed‐laser‐deposited (PLD) barium titanate (BTO) thin‐films on a magnesium oxide substrate. The frequency response of the relative permittivity (dielectric constant) and the linear electro‐optical coefficient (Pockels coefficient) are measured. At 0.2 GHz, the Pockels coefficient is fitted to be r42 ≈ 1030 pm V−1. It decreases to ≈390 pm V−1 at 10 GHz after which it remains constant up to 70 GHz. The unbiased BTO permittivity is measured to be εa ≈ 7600 at 0.2 GHz, dropping to ≈1100 at 67 GHz, while the biased BTO  had a permittivity εa ≈ 2000 at 0.2 GHz, dropping to ≈500 at 67 GHz. These results fill an important experimental characterization gap for high‐speed BTO applications and show the high quality of PLD‐grown BTO films. Lastly, the material's crystalline quality is characterized and the domain distribution is imaged. The findings enable the design and fabrication of a new generation of BTO‐based components for sensing and communications.