Electrical properties of ferroelectric BaTiO3 thin film on SrTiO3 buffered GaAs by laser molecular beam epitaxy

Abstract

Ferroelectric BaTiO3 thin films were epitaxially grown on (001) GaAs substrate using SrTiO3 as a buffer layer by laser molecular beam epitaxy. The perovskite SrTiO3 buffer layer present a body centered cubic structure by formation of an interfacial layer with the [100] SrTiO 3 [110] GaAs in-plane relationship. Thereupon, a highly c -oriented BaTiO3 thin film was grown on SrTiO3 /GaAs in a layer by layer mode. Enhanced electrical properties of the heteroepitaxial structure were demonstrated. The BaTiO3 (150 nm) / SrTiO3 /GaAs system demonstrates hysteresis loops with a remnant polarization of 2.5 μC/ cm2 at 600 kV/cm and a small leakage current density of 2.9× 10-7 A/ cm2 at 200 kV/cm.