Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-13T07:03:05.842Z Has data issue: false hasContentIssue false

Use of an External Electric Field to Convert the Paraelectric Phase to the Ferroelectric Phase in Ultra-thin Copolymer Films of P(VDF-TrFE)

Published online by Cambridge University Press:  21 March 2011

Matt Poulsen
Affiliation:
Department of Physics and Astronomy and Center for Materials Research and Analysis, University of Nebraska, Lincoln, NE 68588
S. Adenwalla
Affiliation:
Department of Physics and Astronomy and Center for Materials Research and Analysis, University of Nebraska, Lincoln, NE 68588
Stephen Ducharme
Affiliation:
Department of Physics and Astronomy and Center for Materials Research and Analysis, University of Nebraska, Lincoln, NE 68588
V.M. Fridkin
Affiliation:
Institute of Crystallography, Russian Academy of Sciences, 117333 Moscow, Russia
S.P. Palto
Affiliation:
Institute of Crystallography, Russian Academy of Sciences, 117333 Moscow, Russia
N.N. Petukhova
Affiliation:
Institute of Crystallography, Russian Academy of Sciences, 117333 Moscow, Russia
S.G. Yudin
Affiliation:
Institute of Crystallography, Russian Academy of Sciences, 117333 Moscow, Russia
Get access

Abstract

X-ray diffraction was used to probe the structural changes associated with the conversion of the paraelectric phase to the ferroelectric phase that results from the application of a large external electric field. The samples under study are ultrathin (150 to 250 Å) Langmuir-Blodgett films of the copolymer vinylidene fluoride (70%) with trifluoroethylene (30%) deposited on aluminum-coated silicon. Theta-2theta X-ray diffraction was used to measure the change in inter-layer spacing perpendicular to the film surface. Upon heating at zero external electric field, the crystalline films undergo a structural phase transition, at 100± 5°C, from the all-trans ferroelectric phase to the trans-gauche paraelectric phase. [1,2] Above the phase transition temperature, the non-polar paraelectric phase can be converted back to the polar ferroelectric phase, in a smooth continuous process, using a large external electric field (∼1 GV/m). For example, at 100° C the ferroelectric phase first appears above 0.2 GV/m and increases steadily in proportion while the paraelectric phase decreases until complete conversion to the ferroelectric phase is achieved at approximately 0.6 GV/m.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1) Ducharme, Stephen, Bune, A.V., Blinov, L.M., Fridkin, V.M., Palto, S.P., Sorokin, A.V. and Yudin, S.G., Phys. Rev. B 57, 25 (1998).10.1103/PhysRevB.57.25Google Scholar
2) Choi, Jaewu, Borca, C.N., Dowben, P.A., Bune, A., Poulsen, M., Pebley, S., Adenwalla, S., and Ducharme, S., Phys. Rev. B 61, 5760 (2000).10.1103/PhysRevB.61.5760Google Scholar
3) Lines, M.E. and Glass, A.M., Principles and applications of Ferroelectrics and Related Materials (Clarendon, Oxford 1977).Google Scholar
4) Poulsen, Matt, Undergraduate Thesis (University of Nebraska, Lincoln 2000).Google Scholar
5) Kochervinskii, V.V., Russian Chemical Reviews 65, 865 (1996).10.1070/RC1996v065n10ABEH000328Google Scholar
6) Petty, Michael, Langmuir-Blodgett Films (Cambridge Press, New York 1996).Google Scholar
7) Lovinger, A., Science 220, 1115 (1983).10.1126/science.220.4602.1115Google Scholar
8) Tashiro, K. and Nalwa, H.S., Ferroelectric Polymers, (Marcel Dekker, New York, 1995), Chap. 2.Google Scholar
9) Legrand, J.F., Ferroelectrics 91, 303 (1989).10.1080/00150198908015747Google Scholar