Giant Strain and Induced Ferroelectricity in Amorphous BaTiO3 Films under Poling
نویسندگان
چکیده
We report an effect of giant surface modification of a 5.6 nm thick BaTiO₃ film grown on Si (100) substrate under poling by conductive tip of a scanning probe microscope (SPM). The surface can be locally elevated by about 9 nm under -20 V applied during scanning, resulting in the maximum strain of 160%. The threshold voltage for the surface modification is about 12 V. The modified topography is stable enough with time and slowly decays after poling with the rate ~0.02 nm/min. Strong vertical piezoresponse after poling is observed, too. Combined measurements by SPM and piezoresponse force microscopy (PFM) prove that the poled material develops high ferroelectric polarization that cannot be switched back even under an oppositely oriented electric field. The topography modification is hypothesized to be due to a strong Joule heating and concomitant interface reaction between underlying Si and BaTiO₃. The top layer is supposed to become ferroelectric as a result of local crystallization of amorphous BaTiO₃. This work opens up new possibilities to form nanoscale ferroelectric structures useful for various applications.
منابع مشابه
Effect of morphology and nonbounded interface on dielectric properties of plasma sprayed BaTiO3 Coating
In this research, BaTiO3 thick deposit has been successfully sprayed by air plasma spray. The microstructure and dielectric properties of thick films were investigated by secondary electron microscopy (SEM) and LCR meter respectively. XRD measurement was carried out on plasma sprayed BaTiO3. The results illustrate differences in the crystal structure between plasma sprayed coatings and feed sto...
متن کاملTunable Schottky Barrier in Photovoltaic BiFeO3 Based Ferroelectric Composite Thin Films
We examine the photo-assisted polarization loop in a BiFeO3 thin film under UV light illumination. BiFeO3 thin film prepared by pulsed laser deposition method onto the BaTiO3 thin film and the polarization behavior has been measured under poling voltage. Our results show the engineered polarization due to controllable schottky barrier under inverse poling voltage. This control on schottky barri...
متن کاملEnhancement of ferroelectricity in strained BaTiO3 thin films.
Biaxial compressive strain has been used to markedly enhance the ferroelectric properties of BaTiO3 thin films. This strain, imposed by coherent epitaxy, can result in a ferroelectric transition temperature nearly 500 degrees C higher and a remanent polarization at least 250% higher than bulk BaTiO3 single crystals. This work demonstrates a route to a lead-free ferroelectric for nonvolatile mem...
متن کاملFerroelectricity in ultra-thin perovskite films
We report studies of ferroelectricity in ultra-thin perovskite films with realistic electrodes. The results reveal stable ferroelectric states in thin films less than 10 Å thick with polarization normal to the surface. Under short-circuit boundary conditions, the screening effect of realistic electrodes and the influence of real metal/oxide interfaces on thin film polarization are investigated....
متن کاملSingle crystalline BaTiO3 thin films synthesized using ion implantation induced layer transfer
Layer transfer of BaTiO3 thin films onto silicon-based substrates has been investigated. Hydrogen and helium ions were co-implanted to facilitate ion-implantation-induced layer transfer of films from BaTiO3 single crystals. From thermodynamic equilibrium calculations, we suggest that the dominant species during cavity nucleation and growth are H2, H +, H2O, Ba 2+ and Ba–OH, and that the additio...
متن کامل