20,066 research outputs found

    Macroporous Photonic Crystal Membrane, Methods of Making, and Methods of Use

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    In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, embodiments of the present disclosure, in one aspect, relate to macroporous photonic crystal membranes, structures including macroporous photonic crystal membranes, devices including macroporous photonic crystal membranes, methods of using macroporous photonic crystal membranes, methods of making macroporous photonic crystal membranes, and the like

    Study of resonant modes in a 700 nm pitch macroporous silicon photonic crystal

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    In this study the modes produced by a defect inserted in a macroporous silicon (MP) photonic crystal (PC) have been studied theoretical and experimentally. In particular, the transmitted and reflected spectra have been analyzed for variations in the defect’s length and width. The performed simulations show that the resonant frequency is more easily adjusted for the fabricated samples by length tuning rather than width. The optimum resonance peak results when centered in the PC bandgap. The changes in the defect geometry result in small variations of the optical response of the PC. The resonance frequency is most sensitive to length variations, while the mode linewidth shows greater change with the defect width variation. Several MPS photonic crystals were fabricated by the electrochemical etching (EE) process with optical response in the range of 5.8 µm to 6.5 µm. Results of the characterization are in good agreement with simulations. Further samples were fabricated consisting of ordered modulated pores with a pitch of 700 nm. This allowed to reduce the vertical periodicity and therefore to have the optical response in the range of 4.4 µm to 4.8 µm. To our knowledge, modes working in this range of wavelengths have not been previously reported in 3-d MPS structures. Experimental results match with simulations, showing a linear relationship between the defect’s length and working frequency inside the bandgap. We demonstrate the possibility of tailoring the resonance peak in both ranges of wavelengths, where the principal absorption lines of different gases in the mid infrared are placed. This makes these structures very promising for their application to compact gas sensors.Postprint (author's final draft

    Highly permeable macroporous polymers synthesized from pickering medium and high internal phase emulsion templates

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    Open porous poly-Plckerlng-M/HIPEs with permeabilities of up to 2.6 D were prepared by polymerisation of PickeringM/HIPEs to which small amounts of surfactant were added. The permeability of these poly-Pickering-M/HIPEs is more than 5 times that of conventional polyHI PEs. This approach allows the synthesis of a novel class of permeable particle reinforced macroporous polymers with significant potential for practical exploitation. (Figure Presented) © 2010 WILEY-VCH VerlagGmbH S.Co. KCaA, Weinheim

    Macroporous materials: microfluidic fabrication, functionalization and applications

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    This article provides an up-to-date highly comprehensive overview (594 references) on the state of the art of the synthesis and design of macroporous materials using microfluidics and their applications in different fields

    Study of Ni Metallization in Macroporous Si Using Wet Chemistry for Radio Frequency Cross-Talk Isolation in Mixed Signal Integrated Circuits.

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    A highly conductive moat or Faraday cage of through-the-wafer thickness in Si substrate was proposed to be effective in shielding electromagnetic interference thereby reducing radio frequency (RF) cross-talk in high performance mixed signal integrated circuits. Such a structure was realized by metallization of selected ultra-high-aspect-ratio macroporous regions that were electrochemically etched in p- Si substrates. The metallization process was conducted by means of wet chemistry in an alkaline aqueous solution containing Ni2+ without reducing agent. It is found that at elevated temperature during immersion, Ni2+ was rapidly reduced and deposited into macroporous Si and a conformal metallization of the macropore sidewalls was obtained in a way that the entire porous Si framework was converted to Ni. A conductive moat was as a result incorporated into p- Si substrate. The experimentally measured reduction of crosstalk in this structure is 5~18 dB at frequencies up to 35 GHz

    Porous silicon solar cells

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    We developed a new process for the fabrication of crystalline solar cell, based on an ultrathin silicon membrane, taking advantage of porous silicon technology. The suggested architecture allows the costs reduction of silicon based solar cell reusing the same wafer to produce a great number of membranes. The architectures combines the efficiency of crystalline silicon solar cell, with the great absorption of porous silicon, and with a more efficient way to use the material. The new process faces the main challenge to achieve an effective and not expensive passivation of the porous silicon surface, in order to achieve an efficient photovoltaic device. At the same time the process suggests a smart way to selective doping of the macroporous silicon layers despite the through-going pores. © 2015 IEEE. SciVal Topic Prominence  Topic: Porous silicon | Silicon | macroporous silicon Prominence percentile: 66.984  Author keywords nanofabricationporous siliconsilicon nanoelectronicssolar cells Indexed keywords Engineering controlled terms: Crystalline materialsNanoelectronicsNanostructured materialsNanotechnologyPorous siliconSiliconSilicon wafersSolar cells Engineering uncontrolled terms Crystalline silicon solar cellsCrystalline solar cellsMacro porous siliconPhotovoltaic devicesPorous silicon surfacesPorous silicon technologySilicon nanoelectronicsUltrathin silicon membrane Engineering main heading: Silicon solar cells ISBN: 978-146738155-0 Source Type: Conference Proceeding Original language: English DOI: 10.1109/NANO.2015.7388710 Document Type: Conference Paper Sponsors: Nanotechnology Council Publisher: Institute of Electrical and Electronics Engineers Inc. References (9) View in search results format ▻ All Export  Print  E-mail Save to PDF Create bibliography 1 (2012) International Technology Roadmap for Photovoltaics Results 2012. Cited 24 times. ITRPV, Third Edition, Berlin 2012 www.ITRPV.net 2 Lehmann, V., Honlein, W., Stengl, R., Willer, J., Wendt, H. (1992) Verfahren Zur Herstellung Einer Solarzelle Aus Einer Substratscheibe. Cited 6 times. German patent DE4204455C1; Filing date: 29. 01. 3 Brendel, R., Ernst, M. Macroporous Si as an absorber for thin-film solar cells (2010) Physica Status Solidi - Rapid Research Letters, 4 (1-2), pp. 40-42. Cited 22 times. http://www3.interscience.wiley.com/cgi-bin/fulltext/123215552/PDFSTART doi: 10.1002/pssr.200903372 Locate full-text(opens in a new window) View at Publisher 4 Ernst, M., Brendel, R., Ferré, R., Harder, N.-P. Thin macroporous silicon heterojunction solar cells (2012) Physica Status Solidi - Rapid Research Letters, 6 (5), pp. 187-189. Cited 16 times. doi: 10.1002/pssr.201206113 Locate full-text(opens in a new window) View at Publisher 5 Ernst, M., Brendel, R. Macroporous silicon solar cells with an epitaxial emitter (2013) IEEE Journal of Photovoltaics, 3 (2), art. no. 6472253, pp. 723-729. Cited 7 times. doi: 10.1109/JPHOTOV.2013.2247094 Locate full-text(opens in a new window) View at Publisher 6 Ernst, M., Schulte-Huxel, H., Niepelt, R., Kajari-Schröder, S., Brendel, R. Thin crystalline macroporous silicon solar cells with ion implanted emitter (Open Access) (2013) Energy Procedia, 38, pp. 910-918. Cited 2 times. http://www.sciencedirect.com/science/journal/18766102 doi: 10.1016/j.egypro.2013.07.364 Locate full-text(opens in a new window) View at Publisher 7 Nenzi, P., Kholostov, K., Crescenzi, R., Bondarenka, H., Bondarenko, V., Balucani, M. Electrochemically etched TSV for porous silicon interposer technologies (2013) Proceedings - Electronic Components and Technology Conference, art. no. 6575887, pp. 2201-2207. Cited 2 times. ISBN: 978-147990233-0 doi: 10.1109/ECTC.2013.6575887 Locate full-text(opens in a new window) View at Publisher 8 Perticaroli, S., Varlamava, V., Palma, F. Microwave sensing of nanostructured semiconductor surfaces (2014) Applied Physics Letters, 104 (1), art. no. 013110. Cited 3 times. doi: 10.1063/1.4861424 Locate full-text(opens in a new window) View at Publisher 9 De Cesare, G., Caputo, D., Tucci, M. Electrical properties of ITO/crystalline-silicon contact at different deposition temperatures (2012) IEEE Electron Device Letters, 33 (3), art. no. 6142006, pp. 327-329. Cited 28 times. doi: 10.1109/LED.2011.2180356 Locate full-text(opens in a new window) View at Publisher © Copyright 2017 Elsevier B.V., All rights reserved. ◅ Back to results ◅ Previous 3of10 Next ▻  Top of page Metrics Learn more about article metrics in Scopus (opens in a new window)  0 Citations in Scopus 0 Learn more about Field-Weighted Citation Impact Field-Weighted Citation Impact PlumX Metrics Usage, Captures, Mentions, Social Media and Citations beyond Scopus.  Cited by 0 documents Inform me when this document is cited in Scopus: Set citation alert ▻ Set citation feed ▻ Related documents Thin crystalline macroporous silicon solar cells with ion implanted emitter Ernst, M. , Schulte-Huxel, H. , Niepelt, R. (2013) Energy Procedia Multilayer etching for kerf-free solar cells from macroporous silicon Schäfer, S. , Ernst, M. , Kajari-Schröder, S. (2013) Energy Procedia Macroporous silicon solar cells with an epitaxial emitter Ernst, M. , Brendel, R. (2013) IEEE Journal of Photovoltaics View all related documents based on references Find more related documents in Scopus based on: Authors ▻ Keywords ▻ About Scopus What is Scopus Content coverage Scopus blog Scopus API Privacy matters Language 日本語に切り替える 切换到简体中文 切換到繁體中文 Русский язык Customer Service Help Contact us Elsevier Terms and conditions ↗ Privacy policy ↗ Copyright © 2018 Elsevier B.V ↗. All rights reserved. Scopus® is a registered trademark of Elsevier B.V. We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies. RELX Group We developed a new process for the fabrication of crystalline solar cell, based on an ultrathin silicon membrane, taking advantage of porous silicon technology. The suggested architecture allows the costs reduction of silicon based solar cell reusing the same wafer to produce a great number of membranes. The architectures combines the efficiency of crystalline silicon solar cell, with the great absorption of porous silicon, and with a more efficient way to use the material. The new process faces the main challenge to achieve an effective and not expensive passivation of the porous silicon surface, in order to achieve an efficient photovoltaic device. At the same time the process suggests a smart way to selective doping of the macroporous silicon layers despite the through-going pores

    Enhanced surface interaction of water confined in hierarchical porous polymers induced by hydrogen bonding

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    Hierarchical porous polymer systems are increasingly applied to catalysis, bioengineering, or separation technology because of the versatility provided by the connection of mesopores with percolating macroporous structures. Nuclear magnetic resonance (NMR) is a suitable technique for the study of such systems as it can detect signals stemming from the confined liquid and translate this information into pore size, molecular mobility, and liquid−surface interactions. We focus on the properties of water confined in macroporous polymers of ethylene glycol dimethacrylate and 2-hydroxyethyl methacrylate [poly- (EGDMA-co-HEMA)] with different amounts of cross-linkers, in which a substantial variation of hydroxyl groups is achieved. As soft polymer scaffolds may swell upon saturation with determined liquids, the use of NMR is particularly important as it measures the system in its operational state. This study combines different NMR techniques to obtain information on surface interactions of water with hydrophilic polymer chains. A transition from a surface-induced relaxation in which relaxivity depends on the pore size to a regime where the organic pore surface strongly restricts water diffusion is observed. Surface affinities are defined through the molecular residence times near the network surface.Fil: Silletta, Emilia Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Velasco, Manuel Isaac. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Gomez, Cesar Gerardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Strumia, Miriam Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Stapf, Siegfried. Technische Universität Ilmenau; AlemaniaFil: Mattea, Carlos. Technische Universität Ilmenau; AlemaniaFil: Monti, Gustavo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Acosta, Rodolfo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin
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