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Grazing-incidence small-angle X-ray scattering (GISAXS) has been used to structurally characterize model hard and soft gratings of nanotechnological interest. The different gratings exhibit GISAXS patterns with characteristic features that can be associated with their level of order along the direction of periodicity and the length of the lines. Highly ordered gratings, made out of silicon by electron beam lithography, and those nanofabricated on spin-coated polymer films by nanoimprint lithography, exhibit characteristic semicircle-like GISAXS patterns with intensity spots periodically distributed on a semicircle whose radius is related to the incidence angle used. These gratings can be considered as one-dimensional crystalline lattices as provided by computer simulations. Less ordered polymer gratings prepared by the laser-induced periodic surface structuring method exhibit a GISAXS pattern characterized by periodic rod-like scattering maxima whose intensity decreases with increasing horizontal scattering angle. In this case the gratings can be considered as one-dimensional paracrystals. The transition from a rod-like to a semicircle-like GISAXS pattern has been simulated and attributed to the contribution of the form factor by changing the length of the line (ripple). A critical length value for the transition is located at around a few micrometres.

9 pags.; 10 figs.; 1 tab.; 1 app., © 2015 Elsevier Ltd.All rights reserved. A strong impact of crystal morphology on hole mobility is evidenced due to competition between phase separation and structure confinement in P3HT/PCDTBT heterojunctions. We find that domain sizes of both components decrease as film thickness decreases, suggesting an initial advantageous scenario for the efficiency of bulk heterojunction solar cells. However the P3HT/PCDTBT (1:1) films with a thickness of 165 nm and thicker present a dense crystal needle-like morphology while no evidence of needle-like motifs appears in the films 58 nm thick, indicating that confinement inhibiting crystallization takes place due to the very thin P3HT domains of only 40 nm in the thinner sample. The structural studies were correlated with nanoscale charge transport by conductive-AFM. A significant zero-field hole mobility increase is observed for the P3HT/PCDTBT films with increasing thickness. Even more interesting is the fact that a zero-field hole mobility increase of about two orders of magnitude is observed for P3HT domains in a 165 nm blend film compared to a neat P3HT film with similar thickness. This observation is related to the highly conductive network induced in P3HT by the presence of the PCDTBT phase, consisting of needle-like crystals growing from the P3HT domains and acting as bridges through the PCDTBT domains., The authors gratefully acknowledge the financial support of the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT 2011-23455. A. R-R is indebted to MINECO for the tenure of a FPI BES-2013-062620 contract associated to the project MAT2012-33517. We thank the Swiss Light Source for beamtime at PolLux. The PolLux end station was financed by the German Minister für Bildung und Forschung (BMBF) through contracts 05KS4WE1/6 and 05KS7WE1. Parts of this research were carried out at the light source DORIS III at DESY, a member of the Helmholtz Association (HGF). We would like to thank J. Perlich for assistance in using beamline BW4.

The melting transition of a model semicrystalline polymer has been detected by the microcantilever deflection as a function of temperature. Deflection measurements were done on arrays of 8-cantilevers spin coated with the semicrystalline polymer: poly (propylene azelate). The melting of the polymer has been corroborated by grazing incidence wide angle x-ray scattering experiments performed with synchrotron radiation over a single cantilever.

Grazing-incidence small-angle X-ray scattering (GISAXS) can be used to characterize the replica quality of polymer gratings prepared by thermal nanoimprint lithography (NIL). Here it is shown using GISAXS experiments that a series of NIL polymer gratings with different line quality present characteristic features that can be associated with the level of defects per line. Both stamps and NIL polymer gratings exhibit characteristic semicircle-like GISAXS patterns. However NIL polymer gratings with defective lines exhibit GISAXS patterns with an excess of diffuse scattering as compared to those of the corresponding stamps. In a first approach, this effect is attributed to a reduction of the effective length of the lines diffracting coherently as the number of defects per line increases. © Blackwell Publishing 2014., The financial support of MICINN through CTQ2010-15680, MAT2011-23455 and MAT2012-33517 is gratefully acknowledged. ER and IMF thank MICINN, Spain, for a `Ramón y Cajal' contract (RYC-2011-08069) and for an FPI fellowship, respectively. MS and DMT thank CSIC for the tenure of JAE fellowships and the Fondo Social Europeo (FSE) for co-financing the JAE program.

6 p.; gráf., In this work, well-defined low aspect ratio nanostructures based on nanogratings on thin films of poly(vinylidene fluoride trifluoroethylene) copolymers were prepared. By using these nanogratings, an improved management of writing and reading information of about 500 Gbit/in.2(0.01 bit/nm2) can be reached as revealed by Piezoresponse Force Microscopy. Structural investigation by means of X-ray diffraction techniques indicates that the physical confinement generated by nanoimprint promotes the development of smaller and edge-on oriented crystals. Our results evidence that one-dimensional nanostructuring can be a straightforward approach to improve the control of the polarization in ferroelectric polymer thin films.© 2013 AIP Publishing LLC., Supported by MINECO MAT2009-07789, MAT2011-23455, and MAT-2012-33517. JAE-Pre fellowship and a JAE-Doc contract of CSIC and the FSE.