Thickness dependent mechanical and ferroelectric properties of Bi_4Ti_3O_(12) film

摘要

In this paper, we analyze and explain the thickness dependent microstructure, surface morphology evolution, mechanical and electrical properties of lead free bismuth titanate film of molecular formula Bi_4Ti_3O_(12) (BIT). BIT films are grown by chemical solution deposition on Pt(111)/SiO_2/Si substrate. X-ray diffraction (XRD) studies revealed orthorhombic structure and (117) orientation of BIT film which remains unchanged with thickness variation of the films. The Young's modulus and hardness shows improved properties in 1 μm BIT film which is 100.36 and 5.09 GPa respectively. Both the remanent and spontaneous polarization value enhanced upon building the thickness of BIT film up to 2 μm. The remanent and spontaneous polarization of 2 μm BIT film is observed to be 22.79 and 37.87 μC/cm~2. BIT films showed excellent fatigue resistance against polarization reversal over 10~6 cycles of repetitions.