Preparation and Properties of SrBi2Ta2O9 Ferroelectric Thin Films Using Excimer UV Irradiation and Seed Layer

Abstract

Low-temperature processing of SrBi2Ta2O9 (SBT) thin films on Pt(200 nm)/Ti(50 nm)/SiO2/Si substrates was investigated by the sol-gel method. The excimer UV irradiation onto as-deposited SBT thin films at 200–300°C in O2 atmosphere and the use of a Sr–Ta–O seed layer were very effective in lowering the crystallization temperature for SBT thin films to 500°C. The SBT thin films prepared by an excimer UV process and subsequent rapid thermal annealing process with the seed layer showed a homogeneous and smooth surface microstructure with fine grains of approximately 50 nm in size. The 600°C-annealed SBT thin films of approximately 200 nm thickness with the seed layer exhibited a Pr of 2.3 µC/cm2 and a Ec of 43 kV/cm.