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Ferroelectric poly(vinylidene fluoride-co-trifluoroethylene), P(VDF-TrFE), is increasingly used in organic non-volatile memory devices, e.g., in ferroelectric field effect transistors (FeFETs). Here, we report on FeFETs integrating nanoimprinted arrays of P(VDF-TrFE) nanowires. Two previously-unreported architectures are tested, the first one consisting of stacked P(VDF-TrFE) nanowires placed over a continuous semiconducting polymer film; the second one consisting of a nanostriped blend layer wherein the semiconducting and ferroelectric components alternate regularly. The devices exhibit significant reversible memory effects, with operating voltages reduced compared to their continuous film equivalent, and with different possible geometries of the channels of free charge carriers accumulating in the semiconductor. cop. 2015 SPIE.

We demonstrate the fabrication of an organic Ferroelectric Field Effect Transistor (FeFET) incorporating a ferroelectric gate dielectric made of nanostripes obtained by nanoimprinting poly(vinylidene fluoride-co-trifluoroethylene) over a layer of semiconducting poly(triarylamine). The imprinting process results in a decreased switching voltage for the ferroelectric, by a factor of ca. 1.5, resulting in a decreased operating voltage compared to a reference FeFET with a continuous ferroelectric layer. The transistor consists of a large number of nanostripe-gated transistors placed in parallel, which also offers interesting possibilities for a strong size reduction of organic FeFETs.

The invention relates to a nanostructured anti-corrosion coating containing polyelectrolytes, including: at least one main compartment including a multilayer (1) of polyelectrolyte(s), doped with at least one anti-corrosion agent (4), and an upper multilayer (2a) acting as a barrier against the diffusion of the doping agents and having an upper surface corresponding to the upper surface of the main compartment; and optionally one or more secondary compartments each including a multilayer (8, 11) of polyelectrolyte(s), doped with at least one functional agent different from an anti-corrosion agent, and an upper multilayer (2b; 2c) acting as a barrier against the diffusion of the doping agents and having an upper surface corresponding to the upper surface of the secondary compartment. The invention also relates to a structure including a metal substrate and such a coating, to the use thereof in the field of aeronautics or aerospace, and to a method for making the same.

The effect of stretching on the thermal cond. of polyethylene (PE) films is presented and compared to results obtained previously for oriented polyacetylene films and PE fibers. As expected, the longitudinal thermal cond. increases with the stretching level and thermal cond. values comparable to those obsd. on metallic alloys are obtained on ultra-drawn PE films. Above a certain stretching level which depends on the polymer, the thermal cond. does not increase any more and becomes either independent on an increase in the drawing level or decreases with it. In the transverse direction, the thermal cond. is slightly lower than that of the isotropic polymer at high temp. The temp. dependence of the transverse thermal cond. of drawn films varies much like that of the isotropic polymer, while the longitudinal cond. decreases more rapidly with decreasing temp. (T2 variation). On the drawn PE films, a dip is obsd. in the temp. dependence between 8 and 17 K, both in the longitudinal and in the transverse direction. This anomaly is much pronounced in the transverse direction.