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Pietroy D.,Laboratoire Des Technologies Of La Microelectronique | Parriaux O.,CNRS Hubert Curien Laboratory | Epalle T.,Jean Monnet University | Tonchev S.,CNRS Hubert Curien Laboratory
Sensors and Actuators, B: Chemical | Year: 2011

The contactless measurement of the sole modulus of the reflection coefficient of a grating-coupled slab waveguide sensor at three definite points of the reflection spectrum gives all necessary information for the determination of the complete set of phenomenological parameters of a waveguide grating (bio)chemical sensor thanks to a physically meaningful representation of the resonant reflection of a free space wave in the form of a circle in the complex plane. This property leads to a simple, non-destructive, wafer-scale functional testing methodology for grating-coupled (bio)chemical sensor chips. © 2011 Elsevier B.V.

Picollo F.,National Institute of Nuclear Physics, Italy | Picollo F.,University of Turin | Picollo F.,National Interuniversity Consortium for the Physical science of Matter | Rubanov S.,University of Melbourne | And 19 more authors.
Acta Materialia | Year: 2016

We report on the structural modifications induced by a λ = 532 nm ns-pulsed high-power laser on sub-superficial graphitic layers in single-crystal diamond realized by means of MeV ion implantation. A systematic characterization of the structures obtained under different laser irradiation conditions (power density, number of pulses) and subsequent thermal annealing was performed by different electron microscopy techniques. The main feature observed after laser irradiation is the thickening of the pre-existing graphitic layer. Cross-sectional SEM imaging was performed to directly measure the thickness of the modified layers, and subsequent selective etching of the buried layers was employed to both assess their graphitic nature and enhance the SEM imaging contrast. In particular, it was found that for optimal irradiation parameters the laser processing induces a six-fold increase the thickness of sub-superficial graphitic layers without inducing mechanical failures in the surrounding crystal. TEM microscopy and EELS spectroscopy allowed a detailed analysis of the internal structure of the laser-irradiated layers, highlighting the presence of different nano-graphitic and amorphous layers. The obtained results demonstrate the effectiveness and versatility of high-power laser irradiation for an accurate tuning of the geometrical and structural features of graphitic structures embedded in single-crystal diamond, and open new opportunities in diamond fabrication. © 2015 Acta Materialia Inc.

Gourgon C.,Laboratoire Des Technologies Of La Microelectronique | Ferchichi A.K.,Laboratoire Des Technologies Of La Microelectronique | Pietroy D.,Laboratoire Des Technologies Of La Microelectronique | Haatainen T.,VTT Technical Research Center of Finland | Tesseire J.,Saint - Gobain
Microelectronic Engineering | Year: 2012

Scatterometry technique has been used to characterize Thermal Step and Repeat NIL processes in the framework of NAPANIL project. Two hundred and fifty nanometers dense lines were imprinted in mr-7030 polymer and their profiles have been analyzed and compared to the mold one. It has been demonstrated that scatterometry on silicon exhibits a very high accuracy and that a change of the sidewall verticality of only few degrees can been measured. The results show that some reflow occurs in lines during the imprint of neighboring dies due to heat diffusion. This phenomenon has been studied as a function of printing temperature, demolding temperature, and space between adjacent dies. The conclusion is that a trade off has to be made between imprint temperature and chuck temperature to be able to fill mold cavities with a limitation of the reflow. © 2012 Elsevier B.V. All rights reserved.

Ferchichi A.K.,Laboratoire Des Technologies Of La Microelectronique | Panabiere M.,Laboratoire Des Technologies Of La Microelectronique | Desplats O.,Laboratoire Des Technologies Of La Microelectronique | Gourgon C.,Laboratoire Des Technologies Of La Microelectronique
Materials Research Express | Year: 2014

This paper investigates the interest of combining NanoImprint Lithography with plasma treatment in order to easily create dual-scale superhydrophobic surfaces on flexible fluorinated foils. The studies were led on FEP and PCTFE materials with conditions compatible with standard NIL equipments. Different pattern geometries, densities and aspect ratio have been investigated and we show that patterning at a nanometer scale improves hydrophobic behaviour compared to microstructuration. Water-contact angle (WCA) of 154° (and water contact angle hysteresis of 11 ± 2°) were measured, which corresponds to a superhydrophobic surface. However, patterning large surfaces at nanoscale with a high aspect ratio is more difficult to achieve and limits the use of such a process for industrial applications. So, we have decided to induce a nanopatterning on microstructures previously printed using plasma etching. This plasma roughening leads to a highly superhydrophobic surface and WCA values as high as 170°. © 2014 IOP Publishing Ltd.

Jageler-Hoheisel T.,CNRS Toulouse Center for Materials Elaboration and Structural Studies | Jageler-Hoheisel T.,TU Dresden | Cordeiro J.,Laboratoire Des Technologies Of La Microelectronique | Lecarme O.,Laboratoire Des Technologies Of La Microelectronique | And 6 more authors.
Journal of Physical Chemistry C | Year: 2013

When a large number of similar gold particles are organized into complex architectures, the dipolar plasmon spectrum of the individual plasmonic entities gives rise to a broader, red-shifted feature centered around 750 nm. In this work, we show that superstructures fabricated using the convective assisted capillary force assembly method (CA-CFA) and excited at that wavelength display a subwavelength patterning of their optical field intensity that results from the self-consistent coupling between the colloidal nanoparticles. First, we demonstrate the fabrication of shape-controlled three-dimensional assemblies of metallic nanocrystals using the CA-CFA method. In a second step, the absorption band resulting from the mutual coupling between the metallic building blocks is exploited to excite a coupled plasmon mode and map the two-photon luminescence (TPL) by scanning a tightly focused light beam. Highly resolved TPL images show that the morphology of the plasmonic particle assemblies has a strong impact on their optical response. A model based on a rigorous optical Gaussian beam implementation inside a generalized propagator derived from a three-dimensional Green dyadic function accurately reproduces the TPL maps revealing the influence of interparticle separation and thus coupling between the individual particles. Finally, we show that the spatial distribution of the electric field intensity can be controlled by tuning the linear polarization of the optical excitation. © 2013 American Chemical Society.

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