Metal Alkoxide Solution-Derived Epitaxial Lead Titanate-Based Thin-Film Optical Waveguides

Abstract

Lead titanate-based thin films were prepared for optical waveguide studies by nonhydrolyzed methoxyethoxide-solution-derived solid-phase epitaxy. PbTiO3 thin films crystallized with preferred (001) and (100) orientations on SrTiO3 (100) and MgO (100), respectively. PLT (28/100) thin films had obvious grain structure although they crystallized with a single (110) orientation on sapphire (011̄2) substrates. Epitaxial PZT thin films with a single (100) orientation crystallized on MgO (100) also had obvious grain structure. Epitaxial PZT (52/48) thin films on SrTiO3 (100) had a single (001) orientation, rocking curve full width at half-maximum of around 0.1°, and smooth surface of rms roughness less than 2 nm. The epitaxial PZT thin films on SrTiO3 showed optical propagation loss as small as 8 dB/cm at 633 nm.