Effect of Thermal Cycling on the Ferroelectric Characteristics of Vinylidene Fluoride-Trifluoroethylene Copolymer Thin Films


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Thin films of polyvinylidene (PVDF) and its copolymers containing 50 to 30 mole % of trifluoroethylene (TrFE) demonstrate rapid reversal of polarization under applied electric field, and can be used as ferroelectric materials in non-volatile memory devices. In this study, Fourier-transform infrared transmission (FTIR-TS) and grazing incident reflection absorption (FTIR-GIRAS) spectroscopy techniques were used to examine the changes in Curie transition temperature (Tc), chain and dipole orientation in selected VDF copolymer spun-cast films as a subjected to a reversible thermal-cycling treatment. A reversible solid-to-solid β-crystalline phase transition with thermal hysteresis and a favorable C-F dipole orientation along the electric field direction were observed for the sample subjected to thermal-cycling below its melting point (Tm). An irreversible β-crystalline phase transition with unfavorable C-F dipole orientation was observed for the sample treated to heating-cooling cycle above Tm. The results are reported in detail here.



Edited by:

D. Rajan Babu




P. Sathiyanathan et al., "Effect of Thermal Cycling on the Ferroelectric Characteristics of Vinylidene Fluoride-Trifluoroethylene Copolymer Thin Films", Advanced Materials Research, Vol. 584, pp. 201-204, 2012

Online since:

October 2012




[1] W. A. Yee, M. Kotaki, Y. Liu, X. Lu, Morphology, polymorphism behaviour and molecular orientation of electrospun poly(vinylidene fluoride) fibers, Polymer, 48 (2007) 512.

DOI: https://doi.org/10.1016/j.polymer.2006.11.036

[2] Q.M. Zhang, H. Xu, F. Fang, Z.Y. Cheng, F. Xia, H. You, Irreversible extinction of ferroelectric polarization in P(VDF-TrFE) thin films upon melting and recrystallization, J. Appl. Phys. 89 (2001) 2613.

[3] K.J. Kim, N.M. Reynolds, S.L. Hsu, Spectroscopic analysis of the crystalline and amorphous phases in a vinylidene fluoride/trifluoroethylene copolymer, Macromolecules, 22 (1989) 4395-4401.

DOI: https://doi.org/10.1021/ma00202a001

[4] A.A. Prabu, J.S. Lee, K.J. Kim, H.S. Lee, Infrared spectroscopic studies on crystallization and Curie transition behavior of ultrathin films of P(VDF/TrFE) (72/28), Vib. Spectros. 41 (2006) 1–13.

DOI: https://doi.org/10.1016/j.vibspec.2005.11.005

[5] J.S. Lee, A.A. Prabu, Y.M. Chang, K.J. Kim, ltrathin Ferroelectric P(VDF/TrFE) Copolymer Film in Low-Cost Non-Volatile Data Storage Applications, Macromol. Symp. 249-250(1) (2007) 13-20.

DOI: https://doi.org/10.1002/masy.200750303

[6] J.S. Lee, A.A. Prabu, K.J. Kim C. Park, The Effect of an External Electric Field on Solid-State Phase Transition of P(VDF/TrFE)(72/28), Fibers and Polymers, 8(5) (2007) 456-462.

DOI: https://doi.org/10.1007/bf02875865

[7] S. Yoon, A. A. Prabu, K.J. Kim, C. Park, Metal salt-induced ferroelectric crystalline phase in poly(vinylidene fluoride) films, Macromol. Rapid Commun. 28 (2007) 2158.

DOI: https://doi.org/10.1002/marc.200800108

[8] C.W. Choi, A.A. Prabu, Y.M. Kim, S. Yoon, K.J. Kim C. Park, Comparative electrical bistable characteristics of ferroelectric poly(vinylidene fluoride-trifluoroethylene) copolymer based non-volatile memory device architectures, Appl. Phys. Lett. 93 (2008).

DOI: https://doi.org/10.1063/1.3013835

[9] A.A. Prabu, K.J. Kim, C. Park, Effect of Thickness on the Crystallinity and Curie Transition Behavior in P(VDF/TrFE) (72/28) Copolymer Thin Films using FTIR-transmission Spectroscopy, Vib. Spectros. 49 (2009) 101-109.

DOI: https://doi.org/10.1016/j.vibspec.2008.05.004

[10] J.S. Lee, A.A. Prabu, K.J. Kim, Annealing effect upon chain orientation, crystalline morphology, and polarizability of ultra-thin P(VDF-TrFE) film for nonvolatile polymer memory device, Polymer, 51 (2010) 6319-6333.

DOI: https://doi.org/10.1016/j.polymer.2010.10.053