Texture growth of titanite CaTiSiO ₅ thin films on (111)Pt/(100)Si substrates

Abstract Lead-free antiferroelectric (AFE) materials with non-perovskite structures are of increasing interest for environmentally friendly high-power energy storage applications. Titanite CaTiSiO 5 thin films with different thicknesses were fabricated on (111)Pt/(100)Si substrates by pulsed laser deposition. Post-annealing under oxygen partial pressures of 50 Torr or higher reduced the leakage current density, owing to the suppression of oxygen-vacancy-related defects. XRD analysis confirmed the formation of single-phase monoclinic P 2 1 / a titanite films with 011 preferred orientation. The Lotgering factor for the 011 orientation reached approximately 0.8 for films thicker than 280 nm. With increasing thickness, the relative permittivity decreased from approximately 100 to 50, approaching the value reported for bulk titanite. Films thicker than 280 nm exhibited clear double polarization–electric field hysteresis loops, confirming stable antiferroelectric behavior. These results reveal the thickness-dependent evolution of texture growth and electrical properties in titanite CaTiSiO 5 thin films.