Title :
Ferroelectric properties of sol-gel derived Bi4-xLaxTi3O12 films prepared on Pt/Ti/SiO2/Si substrate
Author :
Park, S.M. ; Baek, J.H. ; Pak, J.M. ; Nam, K.W. ; Seo, C.W. ; Cheong, H.S. ; Park, Gwangseo
Abstract :
The ferroelectric properties of Bi4-xLaxTi3O12 (BLT) thin films deposited on Pt/Ti/SiO2/Si using sol-gel method have been studied. Their crystal structure, chemical composition and vibration modes were measured using x-ray thetas-2thetas scan, Electron probe micro-scope analyzer(EPMA), and Raman spectroscopy, respectively. Their orientations were domanantly (117) and (200). Various type of grains, lattice expansions and reductions are observed as a function of the content of La and the annealing temperature. The BLT0.25 had larger value of polarization and coercive field than other films, and showed poor fatigue property. However, BLT0.75 film kept a good fatigue property over 101 switching cycles. In this study, we have focused on understanding the features of polarization in terms of the microstructure and the distortion of the unit cell.
Keywords :
X-ray diffraction; annealing; bismuth compounds; coercive force; crystal structure; dielectric hysteresis; dielectric polarisation; fatigue; ferroelectric switching; ferroelectric thin films; lanthanum compounds; platinum; silicon; silicon compounds; sol-gel processing; titanium; vibrational modes; Bi4LaTi3O12; EPMA; Pt-Ti-SiO2-Si; Raman spectra; X-ray thetas-2thetas scan patterns; annealing; chemical composition; coercive field; crystal structure; electron probe microscope analyzer; fatigue property; ferroelectric properties; lattice expansions; microstructure; polarization; sol-gel method; switching cycles; thin films; vibration modes; Bismuth; Chemical analysis; Electrons; Fatigue; Ferroelectric materials; Polarization; Probes; Semiconductor thin films; Sputtering; Vibration measurement;
Conference_Titel :
Applications of Ferroelectrics, 2007. ISAF 2007. Sixteenth IEEE International Symposium on
Conference_Location :
Nara
Print_ISBN :
978-1-4244-1334-8
Electronic_ISBN :
1099-4734
DOI :
10.1109/ISAF.2007.4393191
