Temperature Dependence of Dielectric and Ferroelectric Properties of BiFeO3 Thin Films

Conference · Thu Jan 01 04:00:00 EST 2009

OSTI ID:967132

Biegalski, Michael D ^[1]; Jang, J H ^[2]; Bark, C ^[3]; Eom, Professor Chang-Beom ^[3]

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1. ORNL
2. Univeristy of Wisconsson
3. University of Wisconsin, Madison

Multiferroic materials, with their potential for novel devices and sensors, have spurred an immense amount of research. The most concentrated effort has been on BiFeO3 thin films due to their high N el temperature and high ferroelectric transition temperature. Most studies on BiFeO3 films suffer from electrical leakage, requiring the measurement of dielectric or ferroelectric properties to be conducted at low temperatures. In this work we show that room-temperature leakage is not intrinsic to BiFeO3. Results are shown for highly insulating films, including the temperature dependence (10K to 300K) of the dielectric properties, ferroelectric P-E loops, and leakage current. This data shows very little temperature change in the dielectric constant with a TCC of 0.38 K-1, and dielectric losses below 0.005. The remanent polarization similarly showed no temperature dependence within the error of the measurement with a Pr of 67 1 C/cm2. The leakage current remains below 3x10-4(A/cm2) at 100 kV/cm. This work proves that BiFeO3 does not intrinsically have high leakage, and validates the extrapolation of the properties of BiFeO3 films measured at low temperatures to room temperatures.

• Research Organization: Oak Ridge National Laboratory (ORNL); Center for Nanophase Materials Sciences
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 967132
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DIELECTRIC MATERIALS
DIELECTRIC PROPERTIES
EXTRAPOLATION
LEAKAGE CURRENT
PERMITTIVITY
POLARIZATION
TEMPERATURE DEPENDENCE
THIN FILMS
TRANSITION TEMPERATURE