Effect of contacts on electrical properties of nanostructured porous silicon

En este trabajo se presentan resultados preliminares sobre el estudio del efecto de los contactos metálicos de aluminio sobre las propiedades de transporte eléctrico del silicio poroso nanoestructurado sobre sustratos de vidrio. Se realizaron medidas de TSDC entre 270 y 365 K y de dependencia temporal de la corriente con voltajes de polarización entre 0.1 y 1.5 V. Se analiza el incremento de la corriente cuando se aplica el voltaje y la relajación en condiciones de corto circuito en función del tiempo. A partir de las curvas de corriente vs. tiempo (It) medidas, se obtienen curvas corriente vs. voltaje (IV). Las curvas I-V sugieren un comportamiento tipo Schottky y permiten desestimar un mecanismo Poole-Frenkel. Para V t1(V) la corriente disminuye siguiendo una ley de potencia de la que finalmente se aparta para saturar. Para V > 0.4V el efecto de disminución de la corriente desaparece. Al llevar el voltaje a cero, la corriente muestra un decaimiento abrupto, con cambio de signo para después subir al valor base. Los experimentos de TSDC mostraron una inversion de la corriente.We present preliminary results on the effect of contacts on electrical properties of nanostructured porous silicon supported on glass. TSDC measurements were performed in the 270 - 365 K temperature range. The time dependence of the current for applied bias within the 0.1-1.5V range was also studied. The current increase after the voltage is applied and its relaxation in short circuit conditions are analized. The current-voltage curves (IV) suggest a Schottky behavior, the Poole-Frenkel mechanism being ruled out. When V t1(V) the current decreases following a power law before saturating. For V > 0.4 V the decrease of current is not further observed. When the applied voltage is removed (short-circuit condition), the current decreases abruptly, changes sign and then increases again towards its stationary value. TSDC experiments show a current sign inversion.Fil: Marín Ramírez, Oscar Alonso. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico Para la Industria Química; ArgentinaFil: Comedi, David Mario. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Koropecki, Roberto Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico Para la Industria Química; Argentin

NOVEL NANOSTRUCTURES GROWN BY ELECTROPHORETIC DEPOSITION USING SI SUBSTRATES WITH LOW RESISTIVITY

During the last years, the activity and interest in the science and technology of nanostructures have increased exponentially. The use of nanoparticles, nanowires and other nanostructures in the manufacture of different (such as photovoltaic, electronic, optoelectronic, photonic, biomedical) devices is becoming increasingly important as a result of the benefits provided by the nanoscale. In particular, the nanostructures of transparent conductive oxides (TCO\u27s) and wide bandgap semiconductors (such as ZnO), stand out in opto and microelectronics mainly because they are nanometric building blocks that may enable the fabrication of, respectively, electrical interconnections with relative simplicity and active optoelectronic elements in transparent circuits. Please click Additional Files below to see the full abstract

ZnO Nanowires on Graphite with Improved UV Photoluminescence

INTRODUCTIONBroadband semiconductors (such as ZnO) stand out inopto and microelectronics as they allow the developmentof transparent electronics. ZnO, with its diversenanostructured morphologies (nanowires, nanorods,nanocrystalline thin films, etc.) is an extremely attractivecompound to use in a great variety of nanotechnologicalapplications. ZnO also exhibits a high exciton bidingenergy of 60 meV and a prohibited bandwidth in the UV(3,37 eV), making it a great candidate for applications inoptoelectronics1,2. In this work, a detailed characterizationof the morphology and photoluminescence (PL)properties of ZnO nanowires (NWs) grown on differentcarbon substrate is presented.EXPERIMENTAL STUDYZnO NWs were grown through the vapor-phase transportmethod, on carbon substrates (compacted graphite andcarbon fibers) in a tubular furnace under Ar and O flow.In contrast to NWs grown on Si or other semiconductorsubstrates, metallic catalysers3 are not necessary, as theNWs growth occurs directly on the surface of the carbonsubstrates. The morphology, chemical composition andthe stoichiometry of the NWs grown, as well as the maincharacteristics of the valence band density of states closeto Fermi level, were studied by x-ray photoelectronspectroscopy (XPS). Photoluminescence spectra were alsomeasured.RESULTS AND DISCUSSIONPL dependence with excitation power was measured andanalyzed in the different samples: ZnO NWs oncompacted graphite; ZnO NWs on carbon fibers; ZnONWs transferred on Si; and ZnO crystal (see Fig. 1) aswell as the evolution of the ultraviolet (UV) and greenemission intensities for all the samples (see Fig. 2). Theresults show an increase by 3 orders of magnitude in theUV emission intensity for the NWs grown on compactedgraphite with respect to the UV intensity measured in theothers samples and also in comparison to results obtainedin a previous work4.CONCLUSIONIncreasing the emission efficiency is of great interest forapplications in photonics and UV optoelectronics, and isusually achieved from the inhibition of visible emission,with the consequent increase in UV emission5. However,in the ZnO NWs grown on compacted graphite it wasfound that the high efficiency is produced by aconsiderable increase in UV intensity without the need tosuppress the visible emission.Fil: Tosi, Ezequiel. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; ArgentinaFil: Tirado, Monica Cecilia. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; ArgentinaFil: Zampieri, Guillermo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Comedi, David Mario. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina11th International conference on Advanced Nano MaterialsAveiroPortugalUniversity of Aveir

Influence of substrate morphology on ZnO nanostructures grown by electrophoretic deposition

The potential of nanotechnology depends heavily on the ability to manipulate atoms and nanoparticles with the greatest versatility possible during the manufacturing process of nanostructures. The use of low dimensional structures is a key technological factor in the creation of new functional and sensing devices which benefit from their large surface area to volume ratio. Nevertheless, many properties of nanomaterials depend not only on their size but also on their growth processes. Therefore, it is imperative the quest for a proper understanding and control of the relation between growth processes, structure, morphology, and resulting properties. Among the semiconductor materials, ZnO is considered important and promising. Reasons for this include low-cost, simple and controllable synthesis of a wide diversity of nanostructures, and the interesting potential applications in photonics, and chemical and biological sensing offered by them. In a previous work [1], we reported the self-assembled growth (without a sacrificial template) of ZnO nanowires on Si substrate with Au nanoclusters. The nanowires growth was performed at room temperature by electrophoretic deposition (EPD) from a ZnO nanoparticles colloidal suspension. Since experimental results show that the morphologies and qualities obtained are strongly dependent upon substrate morphology, in the current work we investigate the influence of size, shape and separation between Au nanoclusters on the properties of ZnO nanostructures grown by EPD. The substrates used are commercial Si wafers and Si wafers with amorphous SiO2 layers (grown by thermal oxidation), where a Au nanolayer is deposited by sputtering and annealed at different conditions to produce distinct morphological nanometer-sized Au clusters. The obtained ZnO nanostructures are characterized by scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and photoluminescence spectroscopy. The influence of the morphology of the substrate and process parameters on the quality and morphology of the nanostructures produced is discussed in detail. [1] C. Sandoval, O. Marin, S. Real, D. Comedi, M. Tirado. Electrophoretic deposition of ZnO nanostructures: Au nanoclusters on Si substrates induce self-assembled nanowire growth. Materials Science Engineering B, 187, 21-25 (2014)

Metastability effects on the photoluminescence of ZnO nano-micro structures grown at low temperature and influence of the precursors on their morphology and structure

Nanocrystalline ZnO films were grown on silicon substrate by hydrothermal synthesis at 125 °C, using diethanolamine as stabilizer. A powder containing ZnO spheres, with diameters between 100 to 200 nm and formed by aggregation of ZnO nanoparticles, was also obtained as a secondary reaction product. The samples were studied by scanning electron microscopy, X-ray diffraction and photoluminescence (PL) spectroscopy. The effects of the [diethanolamine]/[Zn+2] molar ratio on morphological, structural and optical properties were studied, as well as the effect of laser illumination (=325 nm) and annealing treatment on photoluminescence properties. The film samples exhibited a compact columnar structure, with thickness between 180 to 210 nm, which were not strongly affected by the diethanolamine concentration. The X-ray diffraction patterns from the films evidenced preferred orientation along the c-axis of the ZnO wurzite structure; while the nanospheres did not show any preferential crystalline direction. The PL spectra from the films showed large initial UV emission and a weak defect band centered in the yellow. A PL evolution while the samples were UV illuminated, attributed to oxygen vacancy generation following the photoinduced equilibration of metastable structures, was observed.Fil: Gonzalez, Vanessa. Instituto de Física del Noroeste Argentino, INFINOA (CONICET-UNT); Argentina. NanoProject - LNPD, Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán; ArgentinaFil: Marín Ramírez, Oscar Alonso. Instituto de Física del Noroeste Argentino, INFINOA (CONICET-UNT); Argentina. NanoProject - LAFISO, Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán; ArgentinaFil: Tirado, Monica Cecilia. Instituto de Física del Noroeste Argentino, INFINOA (CONICET-UNT); Argentina. NanoProject - LNPD, Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán; ArgentinaFil: Comedi, David Mario. NanoProject - LAFISO, Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán; Argentina. Instituto de Física del Noroeste Argentino, INFINOA (CONICET-UNT); Argentin

Effects of methanol on morphology and photoluminescence in solvothermal grown ZnO powders and ZnO on Si

ZnO nano and microstructures were obtained by solvothermal synthesis using hexamethylenetetramine (HMTA) as alkaline agent, and water, water/methanol and methanol as solvents. Two types of samples were obtained: a ZnO powder that grew at the bulk solution and ZnO on silicon substrates. The effect of the solvent on the morphology and optical emission was studied, as well as the influence of the growth zone. With increasing methanol content, the morphology changed from nanorods to nanoparticles powders, and from oriented arrangement of nanorods to thin film on silicon substrates. Important changes in photoluminescence induced by the methanol content and depending on the growth zone were also observed.Fil: Marín Ramírez, Oscar Alonso. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán; ArgentinaFil: González, Vanessa. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán; ArgentinaFil: Tirado, Monica Cecilia. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán; ArgentinaFil: Comedi, David Mario. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán; Argentin

Non-linear excitation of polariton cavity modes in ZnO single nanocombs

Tunable second harmonic (SH) polaritons have been efficiently generated in ZnO nanocombs, when the material is excited close to half of the band-gap. The nonlinear signal couples to the nanocavity modes, and, as a result, Fabry-Pérot resonances with high Q factors of about 500 are detected. Due to the low effective volume of the confined modes, matter-light interaction is very much enhanced. This effect lowers the velocity of the SH polariton in the material by 50 times, and increases the SH confinement inside the nanocavity due to this higher refractive index. We also show that the SH phase-matching condition is achieved through LO-phonon mediation. Finally, birrefringence of the crystal produces a strong SH intensity dependence on the input polarization, with a high polarization contrast, which could be used as a mechanism for light switching in the nanoscale.Fil: Capeluto, Maria Gabriela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires; ArgentinaFil: Grinblat, Gustavo Sergio. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Física del Solido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Tirado, Monica Cecilia. Universidad Nacional de Tucuman. Facultad de Ciencias Exactas y Tecnologia. Departamento de Fisica. Departamento de Nanomateriales y Propiedades Dielectricas; ArgentinaFil: Comedi, David Mario. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Física del Solido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Bragas, Andrea Veronica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires; Argentin

Nanohilos de ZnO con fotoluminiscencia súper eficiente

Se presenta una caracterización detallada de la morfología y propiedades de fotoluminiscencia (PL) en nanohilos (Nhs) de ZnO crecidos por el método de transporte en fase vapor sobre grafito compactado de alta pureza en un horno tubular bajo flujo de Ar y O. En contraste con Nhs crecidos sobre sustratos de Si, no es necesaria la presencia de catalizadores metálicos puesto que el crecimiento de los Nhs sucede directamente sobre la superficie de carbono. Se obtuvo una lámina auto-sostenida de Nhs sin orientación preferencial, de ~60 nm de diámetro y longitudes entre 2 y 6μm. Al estudiar la PL se encontró un incremento de 2 órdenes de magnitud en la eficiencia de emisión (relación entre la emisión de luz UV propia del borde de banda del material y la emisión de luz en el espectro visible debida a estados de defectos en el cristal) en comparación con resultados obtenidos anteriormente para Nhs crecidos sobre Si [1] (ver Figura 1). Aumentar la eficiencia de emisión es de gran interés para aplicaciones en fotónica y optoelectrónica UV, y usualmente se consigue a partir de la inhibición de la emisión visible, con el consiguiente aumento de la emisión UV. No obstante, en este sistema se encontró que la alta eficiencia se produce por un incremento considerable de la intensidad UV sin necesidad de suprimir la emisión visible. Para explicar este fenómeno se analiza la dependencia de la PL con la potencia de excitación poniendo particular atención a la dinámica de activación de los picos de PL.Fil: Tosi, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Física del Sólido; ArgentinaFil: Tirado, Monica Cecilia. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; ArgentinaFil: Comedi, David Mario. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina102ª Reunión de la Asociación Física ArgentinaLa PlataArgentinaAsociación Física Argentin

ZnO nanowire sensitization with Ru polypyridyl complexes: charge-transfer probed by spectral and relaxation photocurrent measurements

Dye-sensitized ZnO nanowire (NW) electrodes were fabricated using Ru polypyridyl complexes that use nitrile instead of carboxylic group as anchoring unit to the NW surfaces. The complexes formula is [Ru(bpy)3−x(Mebpy-CN)x]2+ (x = 1−3, bpy = 2,2'-bipyridine, Mebpy-CN = 4-methyl-2,2'-bipyridine-4'-carbonitrile). The ZnO NWs were grown by a vapor transport method on insulating SiO2/Si substrates. The sensitized ZnO NW electrodes were studied by electron microscopy, Raman and PL spectroscopies, and spectral and relaxation photocurrent measurements. The Raman spectra confirm that the complexes were effectively anchored to the ZnO NWs through one of the pendant nitrile groups of the bipyridyl ligands. The nanostructured morphology of the NW electrodes was maintained so that their light trapping characteristics were preserved. The Ru complexes were found to be excellent sensitizers of the ZnO NWs, improving by orders of magnitude their photocurrent in the visible region. The Fe-based complex of formula [Fe(Mebpy-CN)3](PF6)2 was also tested; however it did not show any sensitizing effect. An order of magnitude shortening of the persistent photocurrent relaxation times (after the illumination is interrupted) was found to occur upon successful sensitization of the ZnO NWs with the Ru complexes. This effect is interpreted in terms of hole traps at ~1 eV above the ZnO valence band edge, which are lowered by ~50–60 meV in the soaked samples due to screening of the trap centers provided by the extra photoexcited charge carriers transferred from the sensitizing complex to the NWs.Fil: Vega, Nadia Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Instituto de Física del Noroeste Argentino, INFINOA. Universidad Nacional de Tucumán, Facultad de Ciencias Exactas y Tecnología, Argentina; ArgentinaFil: Mecchia Ortiz, Juan Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Tirado, Monica Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Instituto de Física del Noroeste Argentino, INFINOA. Universidad Nacional de Tucumán, Facultad de Ciencias Exactas y Tecnología, Argentina; Argentina; ArgentinaFil: Katz, Néstor Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Comedi, David Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Instituto de Física del Noroeste Argentino, INFINOA. Universidad Nacional de Tucumán, Facultad de Ciencias Exactas y Tecnología, Argentina; Argentina; Argentin

ZnO nanorod bunches formation by Electrophoresis Deposition Technique: influence of the conductivity of the substrate

A novel and simple self-assembled direct formation of ZnO nanorod (NR) bunches on boron (p-type)-doped crystalline Si (100) substrates has been achieved by the EPD technique. All the nanostructures were formed from a colloidal dispersion of ZnO NPs in 2-propanol, at room temperature, and without the use of sacrificial templates or pre-deposited Au nanoclusters on Si substrates.ZnO nanoparticle (NPs) colloidal dispersions were prepared based on a modification of the precipitation method reported by Bahnemann et al. [1]. ZnO NPs sizes were estimated from the absorbance spectra of NPs colloidal dispersions and compared to measurements obtained by TEM, which yielded an average diameter of 5 nm with a narrow size distribution, between 4 and 7 nm.The morphology of ZnO NR bunches is affected by the p-type Si substrate wholeconductivity (i.e., B dopant concentration). The nanorod diameters and lengths, as well as thebunch diameters, are larger for substrates with lower conductivity. A ZnO nanoporous film isobtained on non-conductive (nominally undoped) Si substrates without any one-dimensionalformation. XRD patterns indicated that ZnO NRs were preferentially formed in (002) directioncorresponding to c-axis orientation in the wurtzite structure.Photoluminescence (PL) spectra from NR bunches show a low UV excitonic emissionpeak and a broad visible emission peak. The light emission properties of nanostructures arestrongly determined by the properties of NPs used for the EPD deposition and not by thenanostructure morphology. The incorporation of NaOH during ZnO NP synthesis is useful tocomplete reactions of all the available Zn2+ to form dispersions with a higher ZnO NPsconcentration. Therefore, as virtually all the Zn is consumed, PL spectra do not exhibit Zn-typedefects compared to previous work [2].The easy obtaining of different morphologies of ZnO nanostructures depending on the Sisubstrate conductivity is desirable for their use as functional materials in technological devices.The results presented in this work expand the EPD technique applications to form nanorodnanostructures in a single step, representing a high technological potential for nanoscale device applications [3].Fil: Tirado, Mónica. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; ArgentinaFil: Espindola, Omar Alejandro. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; ArgentinaFil: Real, Silvina. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; ArgentinaFil: Zelaya, María Priscila. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; ArgentinaFil: Marín Ramírez, Oscar Alonso. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; ArgentinaFil: Comedi, David Mario. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina14th International Symposium on Electrokinetic Phenomena; 1st Meeting of the International Electrokinetics SocietyTel-AvivIsraelTel-Aviv UniversityIsrael Science Foundatio