Title :
Electrical and optical properties of BiFeO3-PbTiO3 thin films
Author :
Zhou, Xiaowen ; Yu, Shengwen ; Yuan, Bingrong ; Yang, Wufeng ; Cheng, Jinrong
Author_Institution :
Sch. of Mater. Sci. & Eng., Shanghai Univ., Shanghai, China
Abstract :
BiFeO3-PbTiO3 (BFO-PT) thin films were fabricated by sol-gel technology. X-ray diffraction pattern reveals the BFO-PT films are in rhombohedral perovskite phase with random orientations. By Pt/BFO-PT/ITO/glass capacitor structure, co-measurement of electrical and optical responses can be achieved. Remanent polarization of 2Pr~40 muC.cm-2 and leakage current density of 2.5times10-5 A/cm2 at 100 kV/cm are obtained in BFO-PT/ITO/glass, which are comparable to those in BFO-PT film on Pt/Si. The absorption spectrum shows that the light with wavelength less than 500 nm can be absorbed by BFO-PT/ITO/glass, which makes the film presenting in orange-yellow color. The optical band gap of BFO-PT thin film is analyzed and derived to be about 2.9 eV for direct band gap and 2.3 eV for indirect band gap. It indicates that not only ultraviolet but also visible light may affect the motion of electrons/carriers in BFO-PT films. With this idea, BFP-PT film may be expected in integration in optic-electronics with solar source.
Keywords :
MIS structures; X-ray diffraction; bismuth compounds; current density; dielectric hysteresis; dielectric polarisation; ferroelectric thin films; lead compounds; leakage currents; multiferroics; optical constants; permittivity; platinum; ultraviolet spectra; visible spectra; Pt-BFO-PT-ITO-glass capacitor structure; Pt-BiFeO3-PbTiO3-ITO; X-ray diffraction; dielectric constant; dielectric hysteresis loops; electrical property; ferroelectric property; leakage current density; metal-multiferroic-conductive metal oxide structure; optic-electronics; optical band gap; remanent polarization; rhombohedral perovskite phase; sol-gel technology; thin film fabrication; ultraviolet absorption spectrum; visible absorption spectrum; Capacitors; Electron optics; Glass; Indium tin oxide; Optical diffraction; Optical films; Photonic band gap; Semiconductor films; Transistors; X-ray diffraction;
Conference_Titel :
Applications of Ferroelectrics, 2009. ISAF 2009. 18th IEEE International Symposium on the
Conference_Location :
Xian
Print_ISBN :
978-1-4244-4970-5
Electronic_ISBN :
1099-4734
DOI :
10.1109/ISAF.2009.5307584
