abstract
BiFeO3 (BFO) thin films were grown by chemical solution deposition on a range of electrodes to determine their role in controlling the phase formation and microstructure of the films. The crystallization on oxide electrodes followed the sequence: amorphous -> Bi2O2(CO3) -> perovskite, while those on Pt crystallized directly from the amorphous phase. IrO2 electrodes promoted perovskite phase formation at the lowest temperature and LaNiO3 additionally induced local epitaxial growth. All compositions exhibited fully coherent Fe-rich precipitates within the grain interior of the perovskite matrix, whereas the incoherent Bi2Fe4O9 second phase was also observed at the grain boundaries of BFO grown on Pt electrodes. The latter could be observed by X-ray diffraction as well as transmission electron microscopy (TEM) but coherent precipitates were only observed by TEM, principally evidenced by their Z contrast in annular dark field images. These data have pronounced consequences for the extended use of BFO films under an applied field for actuator, sensor and memory applications.
keywords
BISMUTH FERRITE; X-RAY; STRESS; IRO2
subject category
Chemistry; Physics
authors
Tomczyk, M; Stroppa, DG; Reaney, IM; Vilarinho, PM
our authors
Monika Malgorzata Tomczyk
PhD Student
Paula Maria Lousada Silveirinha Vilarinho
Vice Directoracknowledgements
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. Monika Tomczyk acknowledges FCT for financial support (SFRH/BD/81123/2011). Ian M. Reaney acknowledges the support of the Engineering and Physical Science Research Council Grant, EP/I038934/1.