Transparent nanometric organic luminescent films as UV-active components in photonic structures

A new kind of visible-blind organic thin-film material, consisting of a polymeric matrix with a high concentration of embedded 3-hydroxyflavone (3HF) dye molecules, that absorbs UV light and emits green light is presented. The thin films can be grown on sensitive substrates, including flexible polymers and paper. Their suitability as photonic active components photonic devices is demonstrated. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

UV laser-induced high resolution cleaving of Si wafers for micro-nano devices and polymeric waveguide characterization

In this work we propose a method for cleaving silicon-based photonic chips by using a laser based micromachining system, consisting of a ND:YVO4laser emitting at 355 nm in nanosecond pulse regime and a micropositioning system. The laser makes grooved marks placed at the desired locations and directions where cleaves have to be initiated, and after several processing steps, a crack appears and propagate along the crystallographic planes of the silicon wafer. This allows cleavage of the chips automatically and with high positioning accuracy, and provides polished vertical facets with better quality than the obtained with other cleaving process, which eases the optical characterization of photonic devices. This method has been found to be particularly useful when cleaving small-sized chips, where manual cleaving is hard to perform; and also for polymeric waveguides, whose facets get damaged or even destroyed with polishing or manual cleaving processing. Influence of length of the grooved line and speed of processing is studied for a variety of silicon chips. An application for cleaving and characterizing sol–gel waveguides is presented. The total amount of light coupled is higher than when using any other procedure

Dye-Based Photonic Sensing Systems

[EN] We report on dye-based photonic sensing systems which are fabricated and packaged at wafer scale. For the first time luminescent organic nanocomposite thin-films deposited by plasma technology are integrated in photonic sensing systems as active sensing elements. The realized dye-based photonic sensors include an environmental NO2 sensor and a sunlight ultraviolet light (UV) A + B sensor. The luminescent signal from the nanocomposite thin-films responds to changes in the environment and is selectively filtered by a photonic structure consisting of a Fabry Perot cavity. The sensors are fabricated and packaged at wafer-scale, which makes the technology viable for volume manufacturing. Prototype photonic sensor systems have been tested in real-world scenarios.The authors thank the EU (Phodye Strep Project 033793 and ERC Starting Grant M&M's 277879), and the Spanish Ministry of Economy and Competitiveness (MAT-2010-21228) and Junta de Andalucia (P09-TEP-5283) for financial support.Aparicio, F.; Alcaire, M.; González-Elipe, A.; Barranco, A.; Holgado, M.; Casquel, R.; Sanza, F.... (2016). Dye-Based Photonic Sensing Systems. Sensors and Actuators B Chemical. 228:649-657. https://doi.org/10.1016/j.snb.2016.01.092S64965722

Sub-micrometric reflectometry for localized label-free biosensing

In this work we present an optical technique for characterizing sub-micrometric areas based on reflectivity of the light as a function of angle of incidence for the two pure polarizations s and p, covering a range of angles of incidence from -71.80 degrees to 71.80 degrees with a resolution of 0.1 degrees. Circular areas with a diameter in the order of 600 nm can be characterized, and the spectra for the two polarizations can be obtained with a single measurement. For biosensing purposes, we have fabricated several Bio Photonic Sensing Cells (BICELLs) consisting of interferometers of 1240 nm of SU-8 polymer over silicon. An indirect immunoassay is performed over these BICELLs and compared experimentally with FT-VIS-NIR spectrometry and theoretical calculations. The Limit of Detection (LoD) achieved is comparable with standard high resolution spectrometry, but with the capability of analyzing sub-micrometric domains for immunoassays reactions onto a sensing surface. (C) 2015 Optical Society of AmericaThis work has been partially funded under the projects under the projects PLATON (Ref: TEC2012-31145) and INNBIOD (Ref: IPT-2011-1429-01000) from the Ministerio de Economia y Competitividad (MINECO) of Spain. We acknowledge Nightingale-EOS and Stephen Morris for his contribution to the development of this optical tool.Casquel, R.; Soler, JA.; Holgado, M.; Lopez, A.; Lavin, A.; De Vicente, J.; Sanza, FJ.... (2015). Sub-micrometric reflectometry for localized label-free biosensing. Optics Express. 23(10):12544-12554. doi:10.1364/OE.23.012544S12544125542310Fan, X., White, I. M., Shopova, S. I., Zhu, H., Suter, J. D., & Sun, Y. (2008). Sensitive optical biosensors for unlabeled targets: A review. Analytica Chimica Acta, 620(1-2), 8-26. doi:10.1016/j.aca.2008.05.022Homola, J. (2008). Surface Plasmon Resonance Sensors for Detection of Chemical and Biological Species. Chemical Reviews, 108(2), 462-493. doi:10.1021/cr068107dBarrios, C. A., Bañuls, M. J., González-Pedro, V., Gylfason, K. B., Sánchez, B., Griol, A., … Casquel, R. (2008). Label-free optical biosensing with slot-waveguides. Optics Letters, 33(7), 708. doi:10.1364/ol.33.000708Estevez, M. C., Alvarez, M., & Lechuga, L. M. (2011). Integrated optical devices for lab-on-a-chip biosensing applications. Laser & Photonics Reviews, 6(4), 463-487. doi:10.1002/lpor.201100025Haes, A. J., & Van Duyne, R. P. (2002). A Nanoscale Optical Biosensor:  Sensitivity and Selectivity of an Approach Based on the Localized Surface Plasmon Resonance Spectroscopy of Triangular Silver Nanoparticles. Journal of the American Chemical Society, 124(35), 10596-10604. doi:10.1021/ja020393xKugel, V., & Ji, H.-F. (2014). Nanopillars for Sensing. Journal of Nanoscience and Nanotechnology, 14(9), 6469-6477. doi:10.1166/jnn.2014.9346Holgado, M., Barrios, C. A., Ortega, F. J., Sanza, F. J., Casquel, R., Laguna, M. F., … Maquieira, A. (2010). Label-free biosensing by means of periodic lattices of high aspect ratio SU-8 nano-pillars. Biosensors and Bioelectronics, 25(12), 2553-2558. doi:10.1016/j.bios.2010.04.042Holgado, M., Casquel, R., Sánchez, B., Molpeceres, C., Morales, M., & Ocaña, J. L. (2007). Optical characterization of extremely small volumes of liquid in sub-micro-holes by simultaneous reflectivity, ellipsometry and spectrometry. Optics Express, 15(20), 13318. doi:10.1364/oe.15.013318Rosencwaig, A., Opsal, J., Willenborg, D. L., Kelso, S. M., & Fanton, J. T. (1992). Beam profile reflectometry: A new technique for dielectric film measurements. Applied Physics Letters, 60(11), 1301-1303. doi:10.1063/1.107323Fanton, J. T., Opsal, J., Willenborg, D. L., Kelso, S. M., & Rosencwaig, A. (1993). Multiparameter measurements of thin films using beam‐profile reflectometry. Journal of Applied Physics, 73(11), 7035-7040. doi:10.1063/1.352421Leng, J. M., Chen, J., Fanton, J., Senko, M., Ritz, K., & Opsal, J. (1998). Characterization of titanium nitride (TiN) films on various substrates using spectrophotometry, beam profile reflectometry, beam profile ellipsometry and spectroscopic beam profile ellipsometry. Thin Solid Films, 313-314, 308-313. doi:10.1016/s0040-6090(97)00838-9Sanza, F. J., Laguna, M. F., Casquel, R., Holgado, M., Barrios, C. A., Ortega, F. J., … Puchades, R. (2011). Cost-effective SU-8 micro-structures by DUV excimer laser lithography for label-free biosensing. Applied Surface Science, 257(12), 5403-5407. doi:10.1016/j.apsusc.2010.10.010Ho, H. P., Law, W. C., Wu, S. Y., Lin, C., & Kong, S. K. (2005). Real-time optical biosensor based on differential phase measurement of surface plasmon resonance. Biosensors and Bioelectronics, 20(10), 2177-2180. doi:10.1016/j.bios.2004.09.01

Photonic sensor systems for the identification of hydrocarbons and crude oils in static and flow conditions

Identification of hydrocarbons and crude oils is typically carried out with samples that, taken from natural sources or refineries, must be brought to the laboratory for their analysis with rather sophisticated instruments. Alternatively, “in situ” procedures have been also developed for this purpose. In this work, we propose the use of a series of several sensor systems based on photonic transducers in the form of chips for the identification and classification of crude oils and hydrocarbons through the determination of their refractive index in the visible and absorption in the near infrared regions of the electromagnetic spectrum. Two of the photonic transducers rely on modifications of a Bragg microcavity and they monitor the changes in visible light interference phenomena that occur in response to the variation of the refractive index of oils. The third one, in the form of a dielectric mirror, monitors the near infrared absorption of crude oils and hydrocarbons through the recording of a transflectance spectrum. The capacity of these transducers for crude oil identification is proved by the analysis of a series of oils and distilled fractions that have been properly identified and classified as a function of their density and partition of long hydrocarbon chains. The three photonic transducers are operated with optical fibers and can be used in static and dynamic modes, this latter under conditions that are especially well-suited for “insitu” analysis of oil streams in real facilities. The proved resistance of the chips to high pressure and temperature conditions supports their suitability to withstand harsh working environments as those existing in extraction wells.Peer reviewe

Cost-effective SU-8 micro-structures by DUV excimer laser lithography for label-free biosensing

Cost-effective SU-8 micro-structures on a silicon substrate were developed using 248 nm excimer laser KrF projection, studying the influence of the different variables on the final pattern geometry, finding out that the most critical are exposure dose and post-bake condition. Also a novel and cost effective type of photomask based on commercial polyimide Kapton produced by 355 nm DPSS laser microprocessing was developed, studying the influence of the cutting conditions on the photomask. Finally, as a likely application the biosensing capability with a standard BSA/antiBSA immunoassay over a 10 × 10 micro-plates square lattice of around 10 ¿m in diameter, 15 ¿m of spacing and 400 nm in height was demonstrated, finding a limit of detection (LOD) of 33.4 ng/ml which is in the order of magnitude of bioapplications such as detection of cortisol hormone or insulin-like growth factor. Low cost fabrication and vertical interrogation characterization techniques lead to a promising future in the biosensing technology field. © 2010 Elsevier B.V. All rights reserved.Funding for the study was provided by the Spanish Ministry of Science and Innovation under BIOPSIA project no. TEC2008-06574-C03.Sanza, FJ.; Laguna, MF.; Casquel Del Campo, R.; Holgado, M.; Angulo Barrios, C.; Ortega Higueruelo, FJ.; López-Romero, D.... (2011). Cost-effective SU-8 micro-structures by DUV excimer laser lithography for label-free biosensing. Applied Surface Science. 257(12):5403-5407. https://doi.org/10.1016/j.apsusc.2010.10.010S540354072571

Bio-Photonic Sensing Cells over transparent substrates for anti-gestrinone antibodies biosensing

[EN] In a previous work we introduced the term Bio-Photonic Sensing Cells (BICELLs), referred to periodic networks of nano-pillar suitable for biosensing when are vertically interrogated. In this article, we demonstrate the biosensing capabilities of a type of micrometric size BICELLs made of SU-8 nano-pillars fabricated over transparent substrates. We verify the biochips functionality comparing the theoretical simulations with the experimental results when are optically interrogated in transmission. We also demonstrate a sensitivity enhancement by reducing the pitch among nano-pillars from 800 to 700. nm. Thus, the Limit of Detection achievable in these types of BICELLs is in the order of 64. pg/mL for 700. nm in pitch among nano-pillars in comparison with 292. pg/mL for 800. nm in pitch when are interrogated by Fourier Transform Visible and Infrared Spectrometry. The experiments exhibited a good reproducibility with a relative standard deviation of 0.29% measured within 8 days for a specific concentration. Finally, BICELLs functionality was tested in real conditions with unpurified rabbit serum for detecting anti-gestrinone antibodies, demonstrating the high performance of this type of BICELLs to detect specific antibodies having immobilized the suitable bioreceptors onto the sensing surface. © 2011 Elsevier B.V.This work is done within the support of the Spanish Ministry of Science and Innovation under project BIOPSIA (REF: TEC2008-06574). The authors thanks the Comunidad de Madrid and Universidad Politecncia de Madrid (Project BIO-VERSATIL, Ref CCG10-UPM/SEM-5096), Generalitat Valenciana (project ACOMP/2010/009 and PROMETEO 2010/008) and Dr Eva Brun for providing the rabbit serum containing polyclonal antibodies for gestrinone studies. F.J.O. is grateful to the Generalitat Valenciana for the postdoctoral grant included in the VALi + d 2010 Programme for Postdoctoral Researchers.Sanza, F.; Holgado, M.; Ortega Higueruelo, FJ.; Casquel Del Campo, R.; López-Romero, D.; Bañuls Polo, MJ.; Laguna, MF.... (2011). Bio-Photonic Sensing Cells over transparent substrates for anti-gestrinone antibodies biosensing. Biosensors and Bioelectronics. 26:4842-4847. https://doi.org/10.1016/j.bios.2011.06.010S484248472

Procedimiento para marcado, encriptación, etiquetado y codificación óptica

Permite el marcaje o grabación de motivos (301) en superficies sobre los que se ha depositado una capa (300) polimérica fluorescente previamente mediante un procedimiento de polimerización por plasma (100) de moléculas de un colorante. El procedimiento combinalas características especiales de las capas poliméricas que lashacen aptas para poder grabar sobre ellas diversos motivos (301)y la posibilidad de grabado mediante láser (101) u otras técnicas. Entre tales características cabe mencionar la posibilidad de tener un efecto visual notable incluso para espesores de 100 nm, eluso de capas no observables cuando se iluminan con luz visible,la alta calidad óptica (transparencia) de las mismas o la facilidad con la que se pueden procesar por tratamientos posteriores, incluido diversos tratamientos mediante láser (101).Peer reviewedConsejo Superior de Investigaciones Científicas (España), Universidad Politécnica de MadridT3 Traducción de patente europe

Micron-scale wedge thin films prepared by plasma enhanced chemical vapor deposition

Wedge-shaped materials are currently employed for optical analyses and sensing applications. In this paper, we present an easy to implement plasma enhanced chemical vapor deposition procedure to grow wedge-shaped thin films with controlled slope at the scale of few hundred microns. The method relies on the use of few tenths micron height obstacles to alter the laminar flow of precursor gas during deposition and is applied for the fabrication of wedge-shaped ZnO thin films. Local interference patterns, refractive index, and birefringence of the films have been measured with one micron resolution using a specially designed optical set-up. Their micro- and nano-structures have been characterized by means of scanning electron microscopy and theoretically reproduced by Monte Carlo calculations.We acknowledge the support of the University of Seville (VPPI‐US), the European Development Funds program (EU‐FEDER), and the Spanish Ministry of Economy and Competitiveness and Agencial Estatal de Investigación (AEI) (projects MAT2013‐40852‐R, MAT2016‐79866‐R, MAT2015‐69035‐R, 201560E055, and MAT2015‐69035‐REDC)