The Surface Structure of Ultra-Thin P(VDF-TrFE) Copolymer Films on Graphite
نویسندگان
چکیده
The structure and local structural distortions, through the polarization manipulation, of crystalline films of ferroelectric vinylidene fluoride (70%) with trifluoroethylene (30%) [P(VDF-TrFE)] copolymer on graphite were studied by scanning tunneling microscopy (STM). A quasi-spiral twist in C-C bonds with rotations about the polymer chain axis was observed by high-resolution STM, indicating a surface relaxation of the strained copolymer films. Such a relaxation behavior appears to be linked to the observed local dipole rotations accompanied by the reversal of the local polarization by biasing the STM tip. A structure model is proposed based upon the observations. PACS number(s): 77.84.Jd; 68.55.Jk; 82.37.Gk; 77.22.Ej; 77.80.Fm # Current address: Department of Electrical and Computer Engineering, the University of Florida * To whom correspondence should be addressed: E-mail: [email protected]
منابع مشابه
Surface structure of ultrathin copolymer films of ferroelectric vinylidene fluoride (70%) with trifluoroethylene (30%) on graphite
The structure and local structural distortions, through the polarization manipulation, of crystalline films of ferroelectric vinylidene fluoride (70%) with trifluoroethylene (30%) [P(VDF-TrFE)] copolymer on graphite were studied by scanning tunneling microscopy (STM). A quasispiral twist in CuC bonds with rotations about the polymer chain axis was observed by high-resolution STM, indicating a s...
متن کاملHot Plate Annealing at a Low Temperature of a Thin Ferroelectric P(VDF-TrFE) Film with an Improved Crystalline Structure for Sensors and Actuators
Ferroelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer 70/30 thin films are prepared by spin coating. The crystalline structure of these films is investigated by varying the annealing temperature from the ferroelectric phase to the paraelectric phase. A hot plate was used to produce a direct and an efficient annealing effect on the thin film. The dielectric, ferroelec...
متن کاملComparison of crystalline thin poly(vinylidene (70%)â•fitrifluoroethylene (30%)) copolymer films with short chain poly(vinylidene fluoride) films
We compare the photoemission and electron energy loss spectra of crystalline poly(vinylidene-fl uoride with trifl uoroethylene: 70%: 30%), P(VDF–TrFE), fi lms, fabricated by the Langmuir–Blodgett technique and annealed in vacuum, with in situ thermally evaporated fi lms of poly(vinylidene-fl uoride) (PVDF) in vacuum. Th e electronic structure and vibrational modes of the short chain PVDF fi lms...
متن کاملRevisiting the δ-phase of poly(vinylidene fluoride) for solution-processed ferroelectric thin films.
Ferroelectric poly(vinylidene-fluoride) (PVDF) has, in the past, been proposed as an ideal candidate for data storage applications as it exhibits a bistable, remanent, polarization that can repeatedly be switched by an electric field. However, fabrication of smooth ferroelectric PVDF thin films, as required for microelectronic applications, is a long-standing problem. At present, the copolymer ...
متن کاملVertically aligned P(VDF-TrFE) core-shell structures on flexible pillar arrays
PVDF and P(VDF-TrFE) nano- and micro- structures have been widely used due to their potential applications in several fields, including sensors, actuators, vital sign transducers, and energy harvesters. In this study, we developed vertically aligned P(VDF-TrFE) core-shell structures using high modulus polyurethane acrylate (PUA) pillars as the support structure to maintain the structural integr...
متن کامل