Night Vision Coming Soon To Cell Phones, Eyeglasses

Adapting technology found in flat screen television sets, scientists have created a thin film that converts infrared light into visible light. The technology could give cell phones, eyeglasses and car windshields cheap, lightweight night vision.

"This device can convert any infrared image into a visible image and would weigh no more than a pair of eyeglasses," said Franky So, a scientist at the University of Florida who describes his new night vision technology in a recent article in the journal Advanced Materials that was funded in part by advanced technology powerhouse DARPA.

Most night vision devices today use massive amounts of electricity -- often several thousand volts, according to So -- and heavy, glass lenses that maintain a vacuum to make the night come alive. So's device takes a radically different turn, replacing glass with thin plastic, eliminating the vacuum and using energy-efficient, organic LEDs.

So does this by using technology borrowed from flat screen TVs. Infrared light enters the film and is detected by the first of seven separate layers, which generates a slight electrical charge. Additional electrical energy -- about three to five volts -- amplifies that signal, which is then converted back into visible light.

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente: http://news.discovery.com/tech/night-vision-cell-phone-eyeglasses.html
Leer: [Jn 17:3]

Engineering researchers simplify process to make world's tiniest wires

Clumps of extremely tiny nanowires in this image are captured with the aid of an electron microscope. The clumping pattern, which occurs as a result of surface tension during the manufacturing process, limits the usefulness of the wires, which are viewed as a likely core element of more powerful microelectronics, solar cells, batteries and medical tools.

-- Surface tension isn't a very powerful force, but it matters for small things — water bugs, paint, and, it turns out, nanowires.
Tests of microscope-slide-sized surfaces, each containing trillions of nanowires, showed that the procedure effectively prevents clumping, Ziegler said.

In this image captured with the aid of an electron microscope, nanowires stand straight up as a result of a new process developed by University of Florida chemical engineering researchers. The engineers apply an electrical charge to the nanostructure during the manufacturing process, charging each wire and making it repel its neighbor, counteracting the opposite force induced by the surface tension. The researchers say the process is inexpensive and simple, a step toward making the nanowires a more common constituent of electronics, medical devices and solar cells.
Nanowires have not found wide commercial applications to date, but Ziegler said that as engineers learn how to make and manipulate them, they could underpin far more efficient solar cells and batteries because they provide more surface area and better electrical properties.

"Being able to pack in a higher density of nanowires gives you a much higher surface area, so you start to generate higher energy density," he said.

Ziegler said that biomedical engineers are also interested in using the wires to help deliver drugs to individual cells, or to hinder or encourage individual cell growth. The University of Florida has applied for a patent on the process, he added.

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente: http://www.physorg.com/news198929565.html
Leer: [Jn7:38]

From ZnO colloidal nanostructures to functional nanomaterials

Fabien Grasset
The transparency and versatile chemistry of nanocolloids can be exploited to fabricate novel thin films.
15 August 2007, SPIE Newsroom. DOI: 10.1117/2.1200708.0805

Thin films are material layers ranging from fractions of a nanometer to several micrometers in thickness. They can be deposited onto metal, ceramic, glass, or semiconductor bases. Among the numerous coating techniques available, chemical or physical vapor deposition and sol-gel methods are the most commonly used in industry. Thin films are mainly used for optical coating and electronic device applications. However, the preparation of low cost functional thin films with high transparency and modulated optical properties remains a challenge for laser, photocatalytic, or display panel applications.

For example, for photocatalysis—which is increasingly used in chemical waste degradation—photostable light-harvesting nanoarchitectures are required: these are nanostructures that can be used to absorb light to facilitate chemical reactions, but are nevertheless robust to the radiation. Were they available, and provided that appropriate semiconductor catalysts were selected, charge carriers could be generated by UV or visible radiation to initiate reduction and oxidation reactions with adsorbed reactants, leading to the destruction of pollutants. However, most photocatalysts consist of metal oxides that are only functional in the UV region. The result is a lack of suitable materials with the appropriate band gap for visible absorption and the required stability for practical applications.

A second example is provided by Y2O3:Eu3+, the most widely used red phosphor for field emission display applications. Much attention has been paid to the synthesis and luminescent properties of Eu3+-doped rare-earth orthoborates (REBO3) thin films. This is due to their desirable properties as ideal vacuum UV phosphors, key materials for the development of plasma display panels. For such phosphors, both luminescence efficiency and color purity are required. Unfortunately, as a red phosphor, the intensity of the red emission of REBO3:Eu3+ is often lower than that of the orange, leading to poor chromaticity.

One of the largest application areas of sol-gel chemistry is thin-film preparation. Using this approach, we started to synthesize ZnO colloidal solutions for the preparation of functional thin films. Zinc oxide is a non-toxic semiconductor with a wide bandgap (3.37eV) and a large exciton binding energy. In bulk or nanosized form, it can be used in a wide range of applications such as UV light emitters, spin functional devices, gas sensors, transparent electronics or surface acoustic wave devices. Using high concentrations of the different polymeric nanocolloids shown in Figure 1(a), we were able to prepare various functional nanomaterials: these include the gels shown in Figure 1(c); the nanosized powders shown in Figure 1(f); the functional thin films (oxynitrides or oxides) produced as plates shown in Figure 1(b) and 1(e); and the fibers shown in Figure 1(d). Recently, red-luminescent Eu,Ti-functionalized ZnO or versatile ZnTiON colored thin films were also developed.

Eu,Ti-functionalized ZnO thin films
As part of these studies, we proposed a chemical alternative to rare-earth (RE) oxides using a very simple and efficient route to prepare highly red-luminescent RE-doped thin films: see Figure 1(b) and (e).1 Using a simple doping process, trivalent europium can easily be introduced in the solution and a Ti-functionalized ZnO can then be used as a nanohost. As shown in Figure 1(b), the red fluorescence of this nanomaterial at room temperature is easily observed under illumination from a compact 4W-UV lamp operating at 254nm. We showed that it was possible to activate RE fluorescence in a highly transparent Ti-functionalized ZnO thin film with simple annealing at 400°C for 15 minutes. The five characteristic emission peaks assigned to the 5D0→7FJ transition of Eu3+ (where J = 0, 1, 2, 3, and 4) are observed, with the strongest emission (J =2) at 613nm (Figure 2, insert).

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente: http://spie.org/x15807.xml?ArticleID=x15807
Leer: [Jn6:63]

Stressed Nanomaterials Display Unexpected Movement- Science News

ScienceDaily (Feb. 24, 2010) — Johns Hopkins researchers have discovered that, under the right conditions, newly developed nanocrystalline materials exhibit surprising activity in the tiny spaces between the geometric clusters of atoms called nanocrystals from which they are made.

This finding, detailed recently in the journal Science, is important because these nanomaterials are becoming more ubiquitous in the fabrication of microdevices and integrated circuits. Movement in the atomic realm can affect the mechanical properties of these futuristic materials -- making them more flexible and less brittle -- and may alter the material's lifespan.

"As we make smaller and smaller devices, we've been using more nanocrystalline materials that have much smaller crystallites -- what materials scientists call grains -- and are believed to be much stronger," said Kevin Hemker, professor and chair of Mechanical Engineering in Johns Hopkins' Whiting School of Engineering and senior author of the Science article. "But we have to understand more about how these new types of metal and ceramic components behave, compared to traditional materials. How do we predict their reliability? How might these materials deform when they are subjected to stress?"

The experiments conducted by a former undergraduate research assistant and supervised by Hemker focused on what happens in regions called grain boundaries. A grain or crystallite is a tiny cluster of atoms arranged in an orderly three-dimensional pattern. The irregular space or interface between two grains with different geometric orientations is called the grain boundary. Grain boundaries can contribute to a material's strength and help it resist plastic deformation, a permanent change of shape. Nanomaterials are believed to be stronger than traditional metals and ceramics because they possess smaller grains and, as a result, have more grain boundaries.

Most scientists have been taught that these grain boundaries do not move, a characteristic that helps the material resist deformation. But when Hemker and his colleagues performed experiments on nanocrystalline aluminum thin films, applying a type of force called shear stress, they found an unexpected result. "We saw that the grains had grown bigger, which can only occur if the boundaries move," he said, "and the most surprising part of our observation was that it was shear stress that had caused the boundaries to move."

"The original view," Hemker said, "was that these boundaries were like the walls inside of a house. The walls and the rooms they create don't change size; the only activity is by people moving around inside the room. But our experiments showed that in these nanomaterials, when you apply a particular type of force, the rooms do change size because the walls actually move."

The discovery has implications for those who use thin films and other nanomaterials to make integrated circuits and microelectromechanical systems, commonly called MEMS. The boundary movement shown by Hemker and his colleagues means that the nanomaterials used in these products likely possess more plasticity, higher reliability and less brittleness, but also reduced strength.

"As we move toward making things at much smaller sizes, we need to take into account how activity at the atomic level affects the mechanical properties of the material," Hemker said. "This knowledge can help the microdevice makers decide on the proper size for their components and can lead to better predictions about how long their products will last."

The journal article describing this discovery was inspired by a Johns Hopkins master's thesis produced by Tim Rupert, then a combined bachelor's/master's degree student in mechanical engineering. Rupert, who is now a doctoral student at MIT, is lead author of the Science piece. Along with Hemker, the co-authors are Daniel Gianola, a former doctoral student and postdoctoral fellow in Hemker's lab who is now an assistant professor of materials science and engineering at the University of Pennsylvania; and Y. Gan of the Karlsruhe Institute of Technology in Germany.

Funding for the research was provided by the U.S. Department of Energy and the National Science Foundation.

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente: http://www.sciencedaily.com/releases/2010/02/100223132019.htm
Leer: [Jn3:16-17]

Electronic Materials Research Lab.

Sputter deposition chamberWelcome to the website for the Electronic Materials Research Lab at Longwood University. In our lab, we fabricate and characterize semiconducting thin-films, bulk materials and nanowires. We conduct research in some pretty exciting areas of materials science that directly contributes to the advancement of technologies such as Blu-Ray, liquid crystal displays, bright-light LEDs, UV detectors, gas sensors and much more.

Students working in the lab gain hands on experience that will carry over seamlessly into the workforce, whether pursuing a career in research, teaching or industry. Specifically, our students work on ultra-high-vacuum systems, atomic force microscopes, electrical characterization tools, thin-film deposition techniques and much more. We fabricate nanowires up to 10,000 times smaller in diameter than a human hair. We measure currents over 1 trillion times smaller than the currents found in your toaster. We have even been known to play around in the machine shop from time to time, fabricating our own parts.

Our two main projects are currently the following: (1) we are investigating the role of the surface in the electrical properties of the wide band-gap semiconductors ZnO and GaN; and (2) we are fabricating and characterizing ZnO nanowires to study I-V behavior and charge transport properties for this quasi-quantum-confined system. We also have a few smaller projects such as the construction of a scanning tunneling microscope that can image surfaces at the atomic level, incorporating our research into the physics curriculum, and physics education research projects..

To learn more about our research, the people involved and the equipment we have available, click on the links at the top of the page, or as follows:

People :: Learn more about the people involved in the lab
Research :: Learn more about our research
Equipment :: Learn more about the types of equipment available in our lab

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente: http://www.longwood.edu/staff/moorejc/
Leer: [Jn3:3]

Thin Film and Nanostructured Materials Physics Group

Welcome to the web site for the Thin Film and Nanostructured Materials Physics Group, Condensed Matter Sciences Division at Oak Ridge National Laboratory. Our research currently addresses two broad scientific challenges, as described below. For detailed examples of our work please see the Research and Personnel pages.

Research on Nanomaterials: Controlled Synthesis and Properties
This research addresses the central challenge of nanoscale science: the need for fundamental understanding of how nanomaterials grow and for control of the growth environment, in order to synthesize materials with new or greatly enhanced properties at attractive rates. The materials focus currently is on carbon nanotubes/nanofibers and on mesoscale oxide films/multilayers for greatly improved ionic conductivity. Part of the research addresses a grand challenge of nanomaterials synthesis: the growth of macroscopic single wall carbon nanotube (SWNT) crystals, and is carried out in collaboration with Rice University. The program’s strength is its integration of three key capabilities: advanced synthesis; time-resolved, in situ diagnostics during growth; and an arsenal of nanomaterials properties measurement and functionalization methods. For synthesis, energetic-beam methods of pulsed laser deposition (PLD), laser vaporization (LV), supersonic chemical beams, and plasma-enhanced chemical vapor deposition (PECVD) are used, together with thermal CVD. A complete suite of time-resolved, in situ diagnostic methods is used to obtain information about the precursor species, temperatures, products, and dynamics of growth in these environments. For ex situ characterization, the program particularly exploits unique ORNL Z-STEM/EELS transmission electron microscopy and spectroscopy to determine structure and composition, now with atomic resolution through aberration correction. This research also involves strong multidisciplinary collaborations with other ORNL and university investigators.

Research on the Emergence of Nanoscale Cooperative Phenomena
This research addresses one of the most important scientific themes of our time, the fundamental and practical importance of understanding complex, self-organizing behavior. Its materials focus is on transition metal oxides (TMOs) and ferroelectric oxides, with special interest in electronically highly correlated materials that exhibit spontaneous electronic phase separation on the meso- to nano-scale. Their astonishing range of properties is believed to result from a variety of possible ground states that lie close together in energy, so that small changes can create new phenomena. The objective is to understand and control such effects in order to design artificially structured TMOs with new combinations of properties. This group's effort is part of a larger ORNL program that integrates three key capabilities: advanced synthesis, detailed characterization (nanoscale to bulk), and theoretical modeling and simulation. For synthesis we have assembled the tools and skills needed to study nanoscale interactions between different electronic phases in 3D (thick or coupled films), 2D (isolated thin layers and superlattices), and quasi-1D (quantum nanowires). For characterization an arsenal of ORNL scanning probe, electronic, magnetic, and transport properties measurements is used, together with Z-contrast scanning transmission electron microscopy (Z-STEM) and electron energy loss spectroscopy (EELS). Aberration-corrected Z-STEM/EELS now permits “seeing” how electronic properties vary, locally and quantitatively, across compositional interfaces, with atomic resolution. For theory, the high-performance computing facilities of ORNL’s Center for Computational Sciences (CCS) are employed together with collaborations between in-house and external theorists, to develop computational approaches suitable for nanoscale highly correlated electronic systems.

Research Impact
The impact of understanding self-organizing behavior, and of finding ways to further direct assembly to make exotic nanoscale properties useful at the macroscale, clearly will be enormous. There undoubtedly are general rules of controlled synthesis and directed assembly to be discovered, and the systematic application of these will result in the addition of many different nanostructured materials to our toolbox. Each success in directed assembly of nanomaterials will make available a new subset of engineering materials, and we know from centuries of experience that the discovery and development of advanced materials always have been the source of new technology.

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente: http://www.tnmp.ornl.gov/
Leer: [Ap22:14]

Characterization of Pentacene-Based Thin Film Transistors using the MM-16 Spectroscopic Ellipsometer.

Céline Eypert - Application Scientist - Thin Film Division

The performance of organic thin-film transistors (OTFTs) using small molecules has considerably improved during recent years. Organic materials have the key advantage of potentially simple and low-temperature thin film processing, using techniques as spin coating, inkjet printing or stamping. This fact suggests that OTFTs could be useful for applications requiring large-area coverage, low temperature processing and low cost.

Organic Thin Film Transistor Structure
Thin film transistors (TFTs) using organic semiconductors as the active material are of interest for a number of applications. Used as pixel-access devices in active-matrix displays, organic TFTs could complement liquid-crystal valves or organic light emitting diodes to allow inexpensive display fabrication on flexible, lightweight polymeric substrates.

Moreover, among the OTFTs with organic semiconductor as the active chanel, those fabricated with pentacene allowed the highest performance. Its high hole mobility approaches or even surpasses the mobility values found in amorphous Si. The most usual gate dielectric in these pentacene devices is thermally grown silicon dioxide on crystalline silicon. The effects of pentacene channel thickness influence the field-effect mobility of the material, and spectroscopic ellipsometry is an ideal, non-destructive tool for its characterization.
Pentacene (C22H14) is a polycyclic aromatic hydrocarbon that contains five benzene rings. There are two types of geometry of organic field effect transistor, below you can see two representations of these structures:

Results
The ellipsometric data were measured using the HORIBA Jobin Yvon MM-16 spectroscopic ellipsometer which is based on liquid crystals modulators. The experimental data were acquired at an angle of 70°across the spectral range 450-850nm. The analysis is made in two steps, firstly the characterization of silicon oxide followed by characterization of the pentacene layer.

Characterization of Silicon Dioxide
A single layer model has been used. The optical properties of the SiO2 are taken from the standard DeltaPsi2 optical library.

Pentacene characterization
The oxide thickness has been fixed in the sample structure of OTFT.
First the model was fitted using the spectral range 600-850nm. The optical constants of the pentacene were determined using a four oscillator dispersion formula. The optical properties were then extended near the lower energies using an advanced function of DeltaPsi2 software: the NK fit.
This NK fit function makes a direct inversion of ellipsometric data to n and k, and allows us to extend a dispersion formula and to characterise features of the refractive index curve that are not possible using a dispersion formula. This function is not based on the Kramers-Kroning relation and must be used with care. For this characterization we believe that this approach provides a valid description of the material’s optical properties.

The model fits the sample perfectly. There is an excellent agreement between the experimental data and the model. Furthermore, the ellipsometry results show a sharp and strong peak in the extinction coefficient k at 654nm, with additional absorption peaks at 630nm, 580nm and 540nm.












Conclusión
Spectroscopic Ellipsometry based on the liquid crystal devices is an excellent technique for the highly accurate characterization of organic semiconductor in OTFTs device in the visible range.


Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente:http://www.horiba.com/fileadmin/uploads/Scientific/Documents/TFilm/lcmse-02.pdf
Leer: [Salm 100]

Solvay and thinfilm enter comercial agreement

Solvay Solexis (“Solvay”) will begin to market its newly developed SolveneTM polymer for applications in printed electronics with its partner Thin Film Electronics ASA (“Thinfilm”).

Thinfilm and Solvay started a collaboration, in 2007, in the field of polymer printed memories, with the goal to optimize Solvay’s ferroelectric polymer materials to enhance the performance of Thinfilm’s memory technology.

“Memory will be a crucial component in the rapidly growing printed electronics market, which is fuelled by new applications. Our partnership with Solvay paves the way for the next generation of printed electronic applications and high volume production of Thinfilm MemoryTM. As we ramp up production with our manufacturing partners, the agreement with Solvay assures commercial supply of memory polymer in large quantities,” says Rolf Åberg, CEO Thinfilm. “Furthermore, this unique polymer composition will make it possible for other companies in Printed Electronics to begin production of Thinfilm Memory.”

“Solvay has identified printable organic electronics as an area of growth that undoubtly will be pushed by the need for more information, everywhere and anytime, of our modern Society. Thinfilm’s innovative technology in printed electronics, gives us an excellent partner in such a quickly emerging field,” says Pierre Joris, Managing Director of Solvay Solexis. “As leader in specialty polymers, Solvay Solexis has experience and know how about developing and producing the sophisticated material solution needed for such applications, which eventually will benefit our customer base.”

Thinfilm’s technology is based on using a ferroelectric polymer as the functional memory material sandwiched between two sets of electrodes. A key competitive advantage of Thinfilm’s memory technology is that it is fully printable in high volume roll-to-roll machines. The jointly developed polymer formulation leverages both Solvay’s and Thinfilm’s intellectual property. Solvay is a world leader in fluoromaterials with more than 4,200 registered patents, while Thinfilm has 15 years of experience and over 100 patents in the field of non-volatile memories using functional polymers.

About Printed Electronics
Printed electronics is the manufacturing of electronic components through the use of printing techniques that utilize functional inks. It is a means to efficiently manufacture electronic components in high volume and on flexible substrates. The combination of new materials, such as the new, unique Solvene TM polymer, new technology such as Thinfilm’s, along with cost effective, large area, high volume deposition and patterning reel-to-reel production processes (i.e., printing), will open up a myriad of new applications. Thin, light-weight, flexible, small, and low cost electronic devices made from polymer will characterize this new and exciting industry, which is projected to grow to US$ 55 billion by 2020, according to IDTechEx, of which about one third is expected to be printed transistors and memory. The applications for such devices include integrated circuits, sensors, flexible displays, memory modules, photovoltaic cells, batteries, rollable solar cells, diagnostic devices, radio frequency identification tags (“RFIDs”), smart packages, and anti-counterfeit and anti-theft devices.

About Thinfilm and Solvay
The Solvay Group is an international industrial Group active in Chemistry. It offers a broad range of products and solutions that contribute to improving quality of life. The Group is headquartered in Brussels and employs about 19,000 people in 50 countries. In 2009, its consolidated sales amounted to EUR 8.5 billion. Solvay is listed on the NYSE Euronext stock exchange in Brussels (NYSE Euronext: SOLB.BE - Bloomberg: SOLB.BB - Reuters: SOLBt.BR). Details are available at www.solvay.com. Solvay Solexis is a fully-owned subsidiary of the Solvay Group. Headquartered in Italy, Solvay Solexis is a major provider of high-end fluorinated material solutions. Visit www.solvaysolexis.com for more information.

Thin Film Electronics ASA (”Thinfilm”) is a Norwegian technology company with head office in Oslo and product development activities in Linköping, Sweden. The company is a pioneer in the use of functional polymer materials for the production of non-volatile electronic memories, and has developed polymer memories with high storage density. Thinfilm is the first in the world able to deliver rewritable memories printed on a commercial scale in a continuous roll-to-roll process. Jointly with its global partners, one expects in the future to also be able to deliver integrated devices containing printed logic elements, enabling the company’s vision of ”Memory Everywhere™”. Thinfilm is listed on the Oslo Axess marketplace at the Oslo Børs (Oslo Stock Exchange) with ticker code ‘THIN’.

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente:http://www.thinfilm.se/news/38-press-releases/210-solvay-and-thinfilmentercommercialagreement?format=pdf

Thinfilm Memory EU Certified

Thin Film Electronics ASA (“Thinfilm”) has received certification that its Thinfilm Memory™ products meet EU standards for safety of toys. Thinfilm has also secured additional funding for go-to-market activities.

After extensive testing by an independent laboratory, Thinfilm has received the EN 71-3 certification that its non-volatile memory products meets the requirements regarding the chemical safety of toys.
“This is an important certification. With several new toys and game concepts under development using Thinfilm Memory, this is well-timed news,” says Davor Sutija, Executive Vice President Thinfilm.
By storing user and game flow information, Thinfilm Memory enables interactive experiences and makes cards and toys ‘intelligent’.“We experience strong interest from inventors and manufacturers of toys and games. They have been searching for the right low-cost technology to empower smart toys,” continues Sutija. Thinfilm is the first in the world to produce fully-printed rewritable non-volatile memories in a high-volume roll-to-roll process.

Additional funding for go-to-market activities secured
Thinfilm announced on 17 June 2010 that additional funding for go-to-market activities has been secured, and that NOK 10 million has been received from investors participating. Over the last 12 months Thinfilm has raised NOK 27 million in the Norwegian market. “This share issue supports the commercialization of Thinfilm Memory; we are very pleased with the support and response from our shareholders,” says Sutija. The redemption of warrants in May was part of a rights issue completed in the second quarter 2009. Warrants were exercisable in the period 6-31 May 2010. More than 80 percent of the outstanding warrants have now been exercised. Remaining warrants may be exercised in November.

About Thinfilm and Printed Electronics
Thinfilm is focused on providing low-power, non-volatile, rewritable polymer memory technology and products in the rapidly growing market of Printed Electronics. Thinfilm’s current main product offering is a 20-bit non-volatile rewriteable memory printed in a high-volume roll-to-roll process.

The Printed Electronics market is still in its early stages, and according to industry analyst group IDTechEx, is expected to grow to more than USD 50 billion in market value over the next ten years. IDTechEx predicts that logic (i.e., memory and transistors) will be the largest segment in this market, representing more than 30 per cent of the total.

Using printing to manufacture electronic memory makes it possible to reduce the number of process steps, dramatically reduce manufacturing costs, as well as the environmental impact as compared to traditional semiconductor processes. Commercial applications of printed electronics include e-paper, electronic readers, and organic light emitting (OLED) displays. Sensors, batteries, and photovoltaic energy sources are also in development, and together with Thinfilm’s memory technology they will open the door to new products and applications.

Memory is an essential part of most electronics. Memory is required for identification, tracking status and history, and is used whenever information is stored. Thinfilm’s non-volatile ferroelectric polymer memory technology is well suited for application with other printed electronics devices because power consumption during read and write is negligible, and as it is permanent, no connection to external power is required for data detainment. Also, the current required to write information is so small that operation would be limited by the battery’s lifetime and not its capacity.

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente:http://www.thinfilm.se/news/38-press-release/211-thinfilmmemoryeucertified?format=pdf

Chips del rollo

Circuitos se van a imprimir en el futuro, como los periódicos de forma rápida y económica, de rodillo a rodillo. Los analistas predicen que las ventas enormes. Uno de los jóvenes carece todavía de la industria: productos listos para el mercado. von Nora Schlüter

En los talleres de Fürth millas PolyIC de funcionamiento de las órbitas de todos los días de la película de plástico transparenEte por medio de prensas enorme. Capa por capa a aplicar estructuras muy finas, un centésimo de milímetro de ancho, una milésima de milímetro de espesor. La tinta puede ser partículas de metal y las moléculas de plástico que dirigen el flujo o detenerse. El producto: Miles de etiquetas de radiofrecuencia, conocido como los chips de RFID. El terminado de copias se entregarán a los proyectos de investigación - o desecharse. Todas las pruebas se ejecuta sólo en el largo camino al mercado.

PolyIC, una joint venture entre Siemens y Leonhard Kurz del fabricante de la película, produce electrónica impresa. La nueva tecnología promete circuitos, la memoria, pantallas y sensores del rollo. Una alternativa a la tecnología de silicio en la actualidad sin igual. Barato, robusto y flexible. A continuación, se utilizará, donde la masa es más importante que el poder de computación: en las etiquetas, que confirman la autenticidad de un producto. En sensores, que miden si los alimentos se ha perdido en la cadena de frío. En las pantallas flexibles para e-Reader. Los nuevos productos que no sustituirá a los chips convencionales, pero los mercados abiertos.

Sin embargo, la joven industria está buscando: la mejor tecnología, materiales avanzados, las aplicaciones más prácticas. Experimentales y de los clientes: "Las empresas a menudo evitan el riesgo de probar las tecnologías de los jóvenes", dice el director Wolfgang Mildner PolyIC. Más de 10 millones de dólares en ventas con circuitos impresos IDTechEx pronostica la agencia de investigación de mercado en 2010. En diez años, sin embargo, sí debería ser de ocho mil millones de dólares.

Los fabricantes de prensa y las empresas químicas, la investigación es ya intenso. Además de las universidades y las empresas como Merck, BASF, SAP y Heidelberger Druckmaschinen están involucrados. € 40 millones en financiación de la investigación es la industria, 40 millones de euros, el Ministerio Federal de Educación e Investigación. "En este momento no existe un mercado real, así que todavía no hay competencia", dice Mildner. "Para superar los obstáculos técnicos, la colaboración es en la actualidad más propicias". Impreso electrónica reunirá a las industrias que antes eran difíciles de contactar. surge en Heidelberg con el Laboratorio de innovación es un laboratorio de investigación de gran tamaño.

El grupo químico Merck violines años ya las diez de plásticos conductores. Hay un centro privado de investigación de los transistores impresos en el Reino Unido, la sede del Grupo en Darmstadt, el aumento de personal. "Vemos en la electrónica impresa, la capacidad de ser una tecnología de punta", dijo Klaus Griesar, jefe de laboratorios concepto de Merck en Alemania. Heidelberg Druckmaschinen mira principalmente al mercado de los envases. "En el largo plazo los dispositivos RFID, sensores y muestra simple, que se integra directamente en el envase", dice Gerd Junghans, gerente de grupo de proyecto para la electrónica impresa.

PolyIC AUXILIOS Prueba de Primeros en La Actualidad Distribuye un potencial Clientes Los. Todavia Se Puede imprimir etiquetas RFID cualquier información Almacenar. Posible ola deberia servicios en dos o el tres Años. La autenticidad de etiquetas Las, controladas PUEDE Pero Por servicios de El lector. Por Ejemplo, Un Solo Funciona dispensador de Jabón Que Si la Recarga uno traves de la Etiqueta de radio de Los Que identifique Como original.

Uno de los primeros productos podrían triunfar en la industria del videojuego: la memoria impresa, diseñado por la empresa noruega Thinfilm, producido por PolyIC. Sólo 20 bits caben en la centímetros cuadrados pocas pequeño chip. Su objetivo es jugar y el comercio de tarjetas, medios de comunicación inteligente. ¿Cuál es la puntuación? ¿Qué nivel ha alcanzado un jugador? Con el equipo adecuado puede leer la información y sobrescribir. Socio es el juego de cartas fabricante belga Carta Mundi. Antes Sutija Thinfilm jefe quiere poner aplicaciones en el mercado el primer partido: "Es una industria innovadora, consciente de los costes con los ciclos de producción cortos." El costo de almacenamiento 5-10 centavos, el lector casi tercero dólares de los EE.UU.

Si es probado, la tecnología en la Carta Mundi, será interesante para las industrias que proporcionan mayores niveles de fiabilidad y durabilidad, tales como la logística y el comercio. Pronto, Sutija, la "memoria está en todas partes."

Nombre y Apellido: Juan J. Núñez C.
Asignatura: CRF
Sección: 01
Fuente:http://www.ftd.de/it-medien/computer-technik/:innovation-chips-von-der-rolle/50139079.html

Thin films seek a solar future

Energy from the sun—available everywhere, for everybody—has motivated research on solar-energy technologies for about three decades. The U.S. Photovoltaic Industry Roadmap, intended to guide companies in developing solar-energy systems, takes a more prosaic but realistic view of the next three decades. It aims for solar energy to provide 10% of U.S. peak generation capacity and supply a considerable share of foreign markets by 2030.

Most photovoltaic (PV) solar technologies rely on semiconductor-grade crystalline-silicon wafers, which are expensive to produce compared with energy from fossil fuel sources. However, potentially less costly thin-film alternatives may make major inroads in the world market in five years, suggests Franz Karg, research manager at the Shell Solar facility in Munich, Germany. Or maybe not. Thin-film solar panels are hard to mass-produce cost-effectively because of the difficulty of coating large areas of glass. “It is my opinion that crystalline- silicon technologies will dominate for at least the next 10 years,” says Jeffrey Mazer of the U.S. Department of Energy (DOE) Office of Solar Energy Technologies (Washington, DC).

Figure 1. The main entrance facade of Technology Place, a research incubator facility for emerging high-tech companies on the Burnaby campus of British Columbia Institute of Technology, incorporates sufficient thin-film solar panels to power all lighting in the building. (British Columbia Institute of Technology)

Solar-energy systems pose many challenges for developers, particularly in the current world economy. Last October, Shell Solar (Amsterdam, The Netherlands) announced the closing of two production operations—in Helmond, The Netherlands, and in Munich—in a restructuring meant to make the c o m p a n y more competitive. The next month, BP Solar (Linthicum, MD) decided to close down production of its thin-film amorphous silicon and cadmium telluride (CdTe) solar panels to focus on crystalline- silicon technologies. “While the thin-film technology continues to show promise, lack of present economics does not allow for continued investment,” said Harry Shimp, BP Solar’s president and chief executive officer.

Figure 2. Copper and indium are deposited by magnetron sputtering, followed by selenization to form the high-absorbing ptype semiconductor CuInSe2, which is combined with an n-type electrode of ZnO to create thin-film solar modules.
(Ian Worpole/Shell Solar, Munich, Germany)

A=Barrier/Mo deposition; B= Laser patterning; C=Cu/In/Se deposition; D=Heat treatment 500°C; E=Chemical deposition 60°C; F=Patterning; G=2nd deposition 200°C; H=Patterning; I=Contacts/lamination

BP’s decision is a setback to the marketing of new thin-film solar technologies. However, First Solar, LLC (Perrysburg, OH), a major maker of CdTe solar cells, remains strongly committed to the technology. Shell Solar continues development of its thin-film technologies. And DOE’s National Renewable Energy Laboratory (NREL) in Golden, Colorado, continues to provide funds for thin-film PV research to its 40 industrial and university partners.

Why solar power?
In 2001, the global market for PV panels and equipment was valued at $2 billion. Worldwide in 2000, solar, geothermal, wind, combustible renewables, and burning garbage and other wastes collectively provided 1.6% of electricity production, according to the International Energy Agency (IEA) in Paris. In its World Energy Outlook 2002, IEA described two scenarios for world energy demand and supply until 2030. One scenario assumes only the continuation of current government measures to stimulate sustainable-energy supply and demand. In it, fossil fuels continue to meet more than 90% of energy demand. All renewables except hydropower grow by 3.3% annually, but they will not meet a large share of the total energy demand because of their low-percentage base. Carbon dioxide (CO²) emissions will grow 70% by 2030 to 38 billion metric tons annually.

In the alternative scenario, governments will implement policies such as promoting energy efficiency, the use of cleaner energy sources, and reducing the environmental impact of producing and burning fossil fuels. Compared with1990, those changes would result in an estimated 16% fewer CO² emissions in 2030—a year when the United Nations estimates the world population will be about 8.3 billion—in part because renewable energy sources will grow rapidly.

Current applications of PV solar panels include providing power to spacecraft and isolated villages in developing countries, solar-energy systems in homes and buildings in Western countries (Figure 1), and even powering the lamps of remote lighthouses. “Especially where there is no connection to the grid, solar energy is easily cheaper than small-scale electricity production with a diesel generator, to give an example,” Karg says. “For electricity production in rural areas in developing countries, solar is the cheaper alternative. To achieve more, we need breakthroughs in large-scale storage of electricity, and solar must be developed in combination with wind, biomass, energy-storage systems, and fossil fuels.”

Most people in solar energy consider government subsidies for R&D and sales as necessary for its successful development and increased usage. Indeed, the PV energy business is still largely dependent on government intervention, and most U.S., European, and Japanese projects are subsidized. The Bush administration seeks $79.7 million from Congress for fiscal year (FY) 2004 to support solar-energy research, up 0.1% from its amended FY 2003 request but down from the $87.1 million that Congress appropriated in FY 2002.

Crafting photovoltaics
PV solar panels convert sunlight directly into electricity. A panel consists of several connected 0.6-V dc PV cells, which are made out of a semiconducting material sandwiched between two metallic electrodes. “The photovoltaic effect refers to the separation of minority carriers [electrons and holes] by a built-in electric field,” such as a pn-junction or Schottky barrier, says DOE’s Mazer. The cells are usually encapsulated behind glass to weatherproof them. In a PV array, several panels are connected to provide sufficient power for common electrical applications such as household electricity. The arrays can be connected to an electricity grid or work as standalone systems.

Researchers at what is now Lucent Technologies’ Bell Laboratories first demonstrated silicon solar cells in 1954, and most PV systems today use mono- or multicrystalline silicon as the semiconducting material. “We obtain monocrystalline wafers by sawing them from silicon rods, which we grow by the Czochralski growth process,” explains Ronald van Zolingen, professor of sustainable energy at the Technical University in Eindhoven, The Netherlands, and a senior business advisor to Shell Solar. “In this process, we pull a monocrystalline rod from a liquid, starting with a small crystal. The growth speed is relatively low. but we obtain excellent material. Monocrystalline silicon solar cells have the advantage of a high efficiency, about 15%, which is an advantage for specific applications.”

Figure 3. A scanning electron micrograph shows a cross section of the p-type semiconductor CuInSe2 film, about 1.5 µm thick, and the n-type layer of ZnO.
(Shell Solar, Munich, Germany)

“We obtain multicrystalline wafers from ingots grown by casting liquid silicon in a large container followed by controlled cooling,” van Zolingen adds. “This technique is less complicated than the pulling of single-crystalline rods. Multicrystalline-silicon solar cells have a slightly lower efficiency than monocrystalline, about 13.5%.” Worldwide, the production of multicrystalline-silicon solar cells outpaces that of monocrystalline-silicon solar cells.

Figure 4. Optical-beam-induced current imaging (in false color) of these four CdS/CuInSe² thin-film solar cells connected in parallel gives a high-resolution photocurrent map, in which defects appear dark.
(University of Waterloo, Ontario, Canada)

Among the major bottlenecks to the output of crystalline-silicon PVs is the high loss of materials during production of the wafers. “In addition, we need to saw the silicon. We typically lose 0.2 mm at the kerf,” says van Zolingen. Despite these problems, crystalline silicon remains the dominant solarcell material. One reason for this is the support provided by the federal government’s PV program since the 1970s for R&D projects focused on crystalline-silicon technologies.

Thin-film alternatives to standard PV solar cells are already available or in development. Amorphous silicon, the most advanced of the thin-film technologies, has been on the market for about 15 years. It is widely used in pocket calculators, but it also powers some private homes, buildings, and remote facilities. An amorphoussilicon solar cell contains only about 1/300th the amount of active material in a crystalline-silicon cell. Amorphous silicon is deposited on an inexpensive substrate such as glass, metal, or plastic, and the challenge is to raise the stable efficiency. The best-stabilized efficiencies achieved for amorphous-silicon solar panels in the U.S. PV program are about 8%. The goal is to produce a stable device with 10% efficiency. United Solar Systems Corp. (Troy, MI) pioneered amorphous-silicon solar cells and remains a major maker today.

Thin-film crystalline-silicon solar cells consist of layers about 10 µm thick compared with 200- to 300-µm layers for crystalline-silicon cells. Researchers at NREL use porous polycrystalline silicon on low-cost substrates and trap light in the silicon to enable total absorption. They have fabricated working solar cells with this material.

New thin films

Copper indium diselenide (CIS) is a more recent thin-film PV material. Siemens Solar developed a process for depositing layers of the three elements on a substrate in a vacuum, and Shell Solar later acquired the technology when it bought Siemens Solar (Figures 2 and 3). CIS modules currently on the market reach stable efficiencies of more than 11%. In the laboratory, NREL scientists have achieved cell efficiencies of 19.2% with the semiconductor. Research now focuses on increasing efficiency (Figure 4), reducing costs, and raising the production yield of CIS panels. Karg predicts that thin-film technology will eventually halve the present production cost per unit kilowatt peak (kWp), which is the peak power that a solar panel can produce at optimum intensity and sun angle (90°). This implies a cost reduction for a complete system of 35% or more.

In 2000, CdTe solar panels were field-tested on a large scale in the United States. NREL researchers consider CdTe a promising material because of its lower cost of production, which uses techniques that include electrodeposition and high-rate evaporation. Prototype CdTe panels have reached 11% efficiency, and research now focuses on improving efficiency and reducing panel degradation at the electrode contacts. “Studies at Brookhaven National Laboratory strongly suggest that CdTe modules can be safely made in a large-scale manufacturing environment, and that CdTe can be safely disposed of when the modules are eventually retired,” Mazer says.

Figure 5. Examples of local photovoltaic installations include, left to right: Tibetan home with 20-W panel and 500-W wind machine (Simon Tsuo); water-pumping station in West Bengal, India (Harin Ullal); and the world's largest residential project, in Amersfoort, The Netherlands (BP Solarex).

Progress in solar PV research and the development of new applications are guided by national and international collaborations between industry and government, such as those described in the U.S. PV roadmap and carried out by national research teams organized by NREL. Japan and Germany have similar ongoing programs, and leading manufacturers are collaborating with other companies to install solar panels on commercial buildings. For example, a recent agreement between Volkswagen and BP Solar calls for installing solar-energy systems on the roofs of the automaker's dealerships throughout Germany. Each company is investing in several different technologies.

Solar's big four

Which PV technologies will dominate future solarenergy markets may depend on the companies developing, manufacturing, and selling them. The four industry leaders are Sharp (Osaka, Japan), BP Solar, Kyocera (Kyoto, Japan), and Shell Solar.

Sharp produces mono- and multicrystalline and amorphous silicon solar cells. The monocrystalline modules have an efficiency of 17.5%, and the multicrystalline cells have 16% efficiency. In 2001, the company shipped 19.2% (75 MWp) of the world's total solar cells. Last July, Sharp opened a new multicrystalline-silicon solar-cell production plant in Nara Prefecture, Japan, and the company's total production capacity now totals 200 MWp.

BP Solar also manufactures nearly 20% of the world's solar-electric panels and systems, using technologies that include polycrystalline solar cells. "We also have our own Saturn technology, which is a highly efficient monocrystalline technology," said a spokesman at BP Solar's U.K. office in Sunbury on Thames, England. The company also sells amorphous silicon thin-film modules. BP developed its proprietary PowerView thin-film silicon laminate partly with funds from NREL. The PV coating converts part of the incoming light into electricity while remaining transparent to the rest of the light. The coating can be used to integrate a solar-energy-generating capacity into building skylights and windowpanes to produce electricity and reduce reliance on utility companies.

Kyocera focuses on off-grid solar systems for private homes in developing countries, communication systems, water pumping, and industry (Figure 5). It sells its own multicrystalline-silicon systems, and amorphous silicon systems produced by United Solar Systems.

Shell Solar makes mono- and multicrystalline silicon as well as thin-film CIS solar systems. It produced solar panels with a total capacity of about 50 MWp in 2002, and it expects to double its crystalline production capacity by 2004. The company now employs about 900 people in the United States, Canada, Portugal, and Germany after cutting 170 jobs last October.

Although the market growth rate for PV solar panels has declined sharply after four years of annual growth of more than 30%, the growth rate is predicted to be 15 to 20% this year and next. Worldwide production capacity almost doubled last year to 760 MWp, up from 400 MWp in 2001. The main producers of these panels have different business strategies. Shell Solar strongly believes in thin-film alternatives, including its CIS technology. Other companies see crystalline silicon as the dominant technology during the next decade.

Few people doubt solar energy's potential, but many wonder when it will be reached. "In the long term, solar may well play an important role," Karg says. "I personally expect a contribution of 10 to 20% of the global electricity production, mainly in the form of grid-connected systems." However, he does not foresee that happening within the next 20 years.

Fuente: http://www.aip.org/tip/INPHFA/vol-9/iss-2/p16.html
Nombre: Juan J. Núñez C.
Materia: CRF
Sección: 01
Leer:[Jn6:55]

GranFilm : Optical Properties of Granular Thin Films-Introduction:

Since the pioneering work of Maxwell Garnett [1] and Mie [2] at the turn of the century, there has been large scientific interest in the optical properties of metallic clusters [3]. Their optical behavior are driven to a large extent by the Mie excitations [3] which can be viewed as surface plasmon-polaritons [4]. Nearly hundred years ago Mie [3] derived an exact theory for the scattering of light from a free standing spherical particle. If, for isolated clusters with simple shapes, such as spheres or spheroids in vacuum, the exact solution of the Maxwell equations is well known, the difficulty of a reliable description of the optical properties of particles dramatically increases for interacting particles of complex shapes, either in a matrix or on a surface. Even though the Maxwell Garnett effective medium theory and other such theories [5] have been quite successful in tackling these questions, an accurate description of the macroscopic optical properties of a collection of particles supported on a substrate, such as the Fresnel coefficients (absorption, reflection and transmission), requires a more sophisticated approach that accounts correctly for the break of symmetry brought by the substrate and for realistic cluster shape. Indeed for clusters deposited on a surface, a quantitative description of the optical properties of thin films is not only hampered by the interactions between aggregates but also by the image interactions between the latter and the substrate [6-9].

In order to handle this latter situation in an adequate way, Bedeaux and Vlieger [10-14] in the first half of the 1970's introduced a model valid for layers whose thickness are in the sub-wavelength regime. In this case, they introduced modified boundary conditions on the surface for the electromagnetic fields which depend on what they called integrated excess quantities. In the closure relation between these quantities, they introduced surface susceptibilities which govern completely the far field behavior of the electromagnetic fields and thus the Fresnel quantities. In this way, they get rid of the complex behavior of the field on the surface. This approach is really analogous to the model of Feibelmann [15] and Barrera [16] who applied these notions in the case of the electromagnetic jump at metallic surfaces. However, Bedeaux and Vlieger were mainly interested in the description of the optical properties of island layers. For such layer, the main quantity which is directly related to the surface susceptibilities is the island polarizability. For simple shape like truncated spheres or spheroids with an axis of revolution normal to the surface of the substrate, a model based on a multipole expansion of the electrical potential in the non retarded limit was developed [17-20]. A nice recent, detailed and pedagogical introduction to this fascinating field of optics can be found in the recent book: Optical properties of Surfaces (Imperial College Press, 2001) by D. Bedeaux and J. Vlieger [21]. The aim of the present web page is to give access to the softwares which englobes most of the models developped in [21]. This software package we have named -- GranFilm.

Fuente: http://web.phys.ntnu.no/~ingves/Software/GranFilm/Current/ we have named -- GranFilm.
Nombre: Juan J. Núñez C.
Materia: CRF
Sección: 01
Leer:[Jn6:35]

Prof. Lars Hultman - Materials Science of Thin Film Nanostructures at Linköping

Abstract
The research program of the Thin Film Group at Linköping concerns the materials science and nanotechnology of thin films. It is aimed at increasing the understanding of vapor phase deposition, ion-surface interactions, and reactions in advanced functional materials. Specifically, we focus on the nature of epilayers, textured films, and nanoscale materials. Model systems include transition metal nitrides, wide-band gap nitrides, multifunctional ceramics (MAX phases; e.g., Ti3SiC2, Ti2AlN), nanocomposites, superlattices, fullerene-like compounds, and nm-sized metallic multilayers. Several deposition techniques are covered including magnetron sputter epitaxy (MSE) and cathodic arc. Our laboratory specializes in applying and developing methods for plasma characterization, analytical and high-resolution electron microscopy, X-ray diffraction, nanoindentation, ab initio calculations, and multi-billion time-step molecular dynamics simulations.

This seminar provides results from studies of nanostructuring in transition metal nitrides, which are used for advanced surface engineering and electronics. Analysis of the TiAlN, TiSiN, ScAlN, and InAlN systems by nanoindentation, XRD, HREM, and Atom Probe Tomography is coupled with ab initio calculations of phase stability and decomposition behavior by lattice mismatch and electronic band structure effects.

Fuente: http://www.campuskista.se/adimo4/%28S%284qaj2hmtm5uipguxu5dk4w45%29%29/Site/kista/web/default.aspx?p=1350&artid=567&artview=full&artcat=calendar&AspxAutoDetectCookieSupport=1
Nombre: Juan J. Núñez C.
Materia: CRF
Sección: 01
Leer:[Jn10:14]

Journal of Vacuum Science and Technology

The name Journal of Vacuum Science and Technology (JVST) combines two scientific journals, JVST A and JVST B, published by the American Vacuum Society since 1964.

1964-1982 Journal of Vacuum Science and Technology [0022-5355]

1983-present Journal of Vacuum Science & Technology. A. Vacuum, surfaces, and films

1983-1990 Journal of Vacuum Science & Technology. B, Microelectronics processing and phenomena

1991-present Journal of Vacuum Science & Technology. B, Microelectronics and nanometer structures

JVST A

Journal of Vacuum Science and Technology A specializes in applied surface science, electronic materials and processing, fusion technology, plasma technology, surface science, thin films, vacuum metallurgy, and vacuum technology.

Editor: G. Lucovsky, Department of Physics, North Carolina State University.

Contnent of the Journal: http://scitation.aip.org/dbt/dbt.jsp?KEY=JVTAD6

JVST B

Journal of Vacuum Science and Technology B specializes in vacuum processing and plasma processing of various materials, the structural characterization, microlithography, and the physics and chemistry of submicrometer and nanometer structures and devices.

Editor: Gary E. McGuire, International Technology Center link required.

Content of the Journal: http://scitation.aip.org/dbt/dbt.jsp?KEY=JVTBD9

External links

Homepage of JVSTA: http://scitation.aip.org/jvsta
Homepage of JVSTB: http://www.avs.org/literature.jvst.b.aspx

Fuente: http://en.wikipedia.org/wiki/Journal_of_Vacuum_Science_and_Technology
Nombre: Juan J. Núñez C.
Materia: CRF
Sección: 01
Leer:[Jn10:14]

Eray Aydil Becomes the New JVST Editor-in-Chief in September

The AVS Board of Directors is pleased to announce the appointment of Professor Eray Aydil as the Editor-in-Chief of the Journal of Vacuum Science and Technology (JVST), the flagship publication of the AVS, effective September 1, 2010. As Editor-in-Chief, he will oversee the editorial operations of both JVST A & B. Professor Aydil will succeed Professor Gerald Lucovsky, who has served as the JVST Editor-in- Chief since 1980.

Eray is a Professor and the Executive Officer of the Chemical Engineering and Materials Science Department at the University of Minnesota and he holds the Ronald L. and Janet A. Christenson Chair in Renewable Energy. He received his B.S. degrees in chemical engineering and in materials science from the University of California, Berkeley, both in 1986. He completed his graduate research at the University of Houston under the supervision of Demetre Economou and received his Ph.D. degree in chemical engineering in 1991.

He then joined the AT&T Bell Laboratories as a Postdoctoral Member of the Technical Staff working with Richard Gottscho. At Bell Labs, he focused on developing and applying surface sensitive diagnostic techniques that can be used in the harsh conditions encountered in plasma etching and deposition reactors.

He joined the faculty of the Chemical Engineering Department at the University of California, Santa Barbara (UCSB) in 1993 as an Assistant Professor and was promoted to Associate Professor with tenure in 1998 and then to full Professor and Vice Chair of the Department in 2001.

At UCSB, he and his students pioneered the development of in situ techniques to monitor composition, dielectric properties, and surface coverage of films during plasma etching and plasma enhanced chemical vapor deposition of materials such as SiO2, fluorinated SiO₂, Si₃N₄, hydrogenated amorphous Si and hydrogenated nanocrystalline Si.

In 2005, Eray joined the faculty of the University of Minnesota Chemical Engineering and Materials Science Department. His research is focused on solving technologically important and fundamental problems encountered in materials processing for applications in electronic and photovoltaic device manufacturing with emphasis on plasma etching and deposition, plasma modification of surfaces, and dye-sensitized and quantum dot solar cells.

He is interested in understanding thin film deposition and etching processes used in the synthesis of nanostructured materials and in manufacturing of integrated circuits and solar cells. He has authored and coauthored over 135 papers and holds 4 patents.

Eray has been an actively-involved member of AVS since he was a graduate student. He served on the editorial board of the JVST between 2004 and 2007. He was a member of the Plasma Science and Technology Division (PSTD) programming committee between 1999 and 2003 and again between 2006 and 2008.

He has served on the PSTD Executive Committee, first as a Member-at-Large between 1999 and 2003 and then as its Chair-Elect, Chair and Past-Chair in 2006, 2007 and 2008, respectively. He was the programming vice-chair of the AVS 56th International symposium in 2009 and he is currently the Chair of the AVS 57th International Symposium and Exhibition that will be held in Albuquerque during October 2010.

Eray received the Norman Hackerman Young Author Award of the Electrochemical Society, the National Young Investigator Award of the National Science Foundation, and the Camille and Henry Dreyfus Teacher- Scholar Award in 1993, 1994 and 1997, respectively. In

1999, he received the AVS Peter Mark Memorial Award “for pioneering work in the development and application of optical diagnostic techniques to understand chemistry and physics associated with plasma deposition of dielectric thin films.” He became a Fellow of the AVS in 2005.

He was awarded the 2009 Plasma Prize at the AVS 56th International Symposium in San Jose. The highest honor of the PSTD, the Plasma Prize is given each year to a researcher who has conducted outstanding research in science and technology of gas plasmas. He received the award for “pioneering work on the characterization of plasma species and their energy distributions in plasma assisted deposition and etching of materials.” He is a dedicated teacher; he has numerous teaching awards both at UCSB and at the University of Minnesota.

In naming Prof. Aydil as Editor-in-Chief, the AVS Board of Directors noted that he brings a breadth of knowledge and experience in research topics that crosscut the various facets of AVS. The Board of Directors is very confident JVST will flourish under his dynamic leadership.

Fuente: http://www.avs.org/
Nombre: Juan J. Núñez C.
Materia: CRF
Sección: 01
Leer:[Jn10:41]

Kinetics of the initial stages of film formation during low pressure chemical vapour deposition of polysilicon by pyrolysis of silane

Abstract

A kinetic model for description of the process of silicon film formation on silica by thermal decomposition of silane at reduced pressure has been proposed. The model is based on the concept of kinetic interdependence between heterogeneous catalytic chemical reaction and fundamental structure forming phenomena - nucleation and nuclei growth. A number of experimental data for deposition rates and polysilicon grains sizes have been mathematically processed in order to derive kinetic equations for the rates of nucleation and nuclei growth as functions of reactor operating conditions (pressure and temperature) as well as process duration. Furthermore, based on both the good correspondence achieved between the experimental results and the model, and the deductions of thermodynamic theory of nucleation, the kinetic equations derived were analysed in regard to the general description of silicon film structure evolution. The analysis of the model, by confïrming the general trends established between the arrival and the surface diffusion rates of silicon adspecies, contributes to clarify the mechanism of the initial stages of film microstructure formation. The results obtained show that kinetics of structure evolution can be successfully described by developing the existing CVD phenomenological kinetic models further to an atomistic level.

Fuente: http://jp4.journaldephysique.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/jp4/pdf/2001/03/jp4200111PR324.pdf
Nombre: Juan J. Núñez C.
Materia: CRF
Sección: 01
Leer: [Jn10:27]

Premium OLED materials for displays

In recent years, Organic Light Emitting Diode (OLED) technology has gained increasing importance for display applications. As one of the leading manufacturers of OLED materials, Merck offers a complete product portfolio of materials for OLED displays, comprising small molecule as well as polymer materials (evaporable and soluble systems), under the brand name livilux®.

Your advantages - High-purity and high-stability materials

Based on more than 10 years of experience in manufacturing OLED materials, a strong worldwide intellectual property position, and the background of more than 100 years of expertise in high-tech product development, we can supply high-purity and high-stability materials that exactly meet customer requirements.

On request, Merck will provide effective application support to optimize the material stack in close cooperation with the customer.

Applications - The world of OLED displays

Merck's OLED materials are used in OLED displays that offer an unparalleled viewing experience with a number of benefits, among them an extremely wide viewing angle, superb video capabilities, very high intrinsic contrast at any viewing angle, a low power consumption for mobile applications, and a remarkable lifetime.

With its extraordinary properties, OLEDs are a promising display technology of the future. Possible applications range from simple passive-matrix monochrome and area-color to active-matrix full-color displays. Today, the technology is used in MP3 players and high-end cell phones and it is likely to soon be used in notebook computers, PC and even TV screens.

The technology - How do OLEDs work?

Based on either small molecule (SM) or polymer (PLED) materials and technologies, OLEDs work by the passage of an electrical current from two conducting electrodes through layers of organic semiconductor materials on a substrate, usually indium tin oxide (ITO) coated glass, silicon, or a special plastic substrate. Light emission is caused by electrically generated electron-hole pairs forming neutral excited states that relax to a ground state with the emission of light. Importantly, each individual OLED material has its own characteristic emission color.

OLED's high precision emissive thin-film structure and excellent optical properties at low power consumption offer considerable advantages to display manufacturers and end users alike. Additionally, as OLEDs are fabricated into extremely thin layer structures and usually need only a single substrate, they are thin, light and potentially offer lower costs.

Fuente:http://www.merck-chemicals.com.ve/lcd-emerging-technologies/oled-materials/c__QOb.s1OuggAAAEh_cUsgkMs?PortalCatalogID=merck4lcds&CountryName=Venezuela
Nombre: Juan J. Núñez C.
Materia: CRF
Sección: 01
Leer:[Jn10:17]

Magnetic Tag Designs: Planar and Pillar Structures

The crux of the technology lies in a sequence of magnetic elements that store information based on their magnetic alignment. Using rectangular or elliptical elements naturally defines two stable states, parallel (and anti-parallel) to the long axis. By assigning each magnetisation direction to be either state 1 or 0, a magnetic barcode is created, and the number of possible combinations doubles with every additional bit, e.g. 10-bit tags can code for up to 1024 different biological compounds .

The group is working on two different tag designs that will be capable of offering a medium number of codes (32 - 8192) in the short-term, and a very large number for gene (re)sequencing applications in the long-term.
Planar Tags:

This tag design features magnetic elements encapsulated in a bio-compatible polymer backbone of size 100μm x 30μm and less than 2μm in thickness. The elliptical magnetic elements are spaced along the length of the backbone and typically only 20nm high, which makes these tags free-floating in aqueous solutions. The tags will be flown through microfluidic channels with integrated sensors where they will be read and sorted in a high-throughput system (see section 3).

Figure 1 a) schematic of a 7-bit equi-element magnetic tag, b) schematic of a 5-bit `multi-coercivity' tag and an F-MOKE image of a real tag.

Fabrication: These structures were grown in a sandwich process, where the SU8 backbones are spin-coated to a thickness of 1μm and shaped using standard photolithographic techniques. A second photolithography step is used to grow and align a PDMS mask on these backbones before vacuum deposition (e.g. evaporation, MBE, sputtering) of the magnetic elements. Finally another 1μm of SU8 is patterned on top, which now protects the magnetic bits from oxditation and the environment.

Figure 2 the main steps in the fabrication of free floating planar tags, (the detailed photolithography has been omitted).

A simplified fabrication procedure uses ion etching and reduces the number of complicated alignment steps, however the pay-off is reduced chemical functionality (see section 4). For details on these tags and their new fabrication procedure, please read the following paper: "Design and Fabrication of SU8 Encapsulated Digital Magnetic Carriers for High Throughput Biological Assays." B. Hong et al., J. App. Phys. 105 034701
Pillar Tags:These tags are aimed at creating an extremely large number of codes (106 to 109), so must be easily scalable for mass production and must be highly cost-effective to manufacture. The coding density is dramatically increased in this design by using a pure metal stack, featuring magnetic elements interleaved with non-magnetic spacers (figure 2). The top is capped with gold to allow a route for chemical modification (see section 4).

Figure 3 (left) schematic of a 10-bit pillar tag, (right) SEM image of a 15μm diameter pillar tag with 8 magnetic layers (some Cu layers are highlighted to aid the eye) and a gold cap, (inset) SEM demonstrating the homogenity of the electrodeposition process.

Fabrication: A single photolithography process is used to define elliptical holes in a non-conducting photo-resist, which is spin-coated onto a conductive substrate. This is usually a 4" silicon wafer with an evaporated novel aluminium/copper bi-layer, which is important for releasing the tags at the end of the process. The substrate is used as the cathode of an electrochemical cell, and when a voltage is applied the metallic ions in the electrolyte are deposited onto the substrate.

Figure 4 The two-step fabrication process: (left) a template is photolithographically defined on a conducting substrate, (right) the substrate is used as the cathode in a basic 3-electrode electrochemical cell.

It is possible to deposit multilayers from a single bath containing a mixture of nickel, cobalt, iron and copper ions, by varying the applied potential, different ions deposit preferentially. This makes this process highly automatable, and material waste is minimised making this procedure ideal for mass production. Further details of this design and fabrication procedure can be found in the following paper: "Digital Biomagnetism: Electrodeposited Multilayer Magnetic Barcodes." J.J. Palfreyman et al., JMMM 321 (10) 1662-1666

Fuente: http://www.tfm.phy.cam.ac.uk/bio/tags.html
Nombre: Juan J. Núñez C.
Materia: CRF
Sección: 01
Leer: [Jn10:14]