Oxide Semiconductor (oxide + semiconductor)

Distribution by Scientific Domains

Kinds of Oxide Semiconductor

  • complementary metal oxide semiconductor
  • metal oxide semiconductor

  • Selected Abstracts

    Fully Transparent Non-volatile Memory Thin-Film Transistors Using an Organic Ferroelectric and Oxide Semiconductor Below 200,°C

    Sung-Min Yoon
    Abstract A fully transparent non-volatile memory thin-film transistor (T-MTFT) is demonstrated. The gate stack is composed of organic ferroelectric poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] and oxide semiconducting Al-Zn-Sn-O (AZTO) layers, in which thin Al2O3 is introduced between two layers. All the fabrication processes are performed below 200,°C on the glass substrate. The transmittance of the fabricated device was more than 90% at the wavelength of 550,nm. The memory window obtained in the T-MTFT was 7.5,V with a gate voltage sweep of ,10 to 10,V, and it was still 1.8,V even with a lower voltage sweep of ,6 to 6,V. The field-effect mobility, subthreshold swing, on/off ratio, and gate leakage currents were obtained to be 32.2,cm2 V,1 s,1, 0.45,V decade,1, 108, and 10,13 A, respectively. All these characteristics correspond to the best performances among all types of non-volatile memory transistors reported so far, although the programming speed and retention time should be more improved. [source]

    Electronic Manifestation of Cation-Vacancy-Induced Magnetic Moments in a Transparent Oxide Semiconductor: Anatase Nb:TiO2

    ADVANCED MATERIALS, Issue 22 2009
    Shixiong Zhang
    Nb-doped anatase TiO2 thin films grown by pulsed-laser deposition show Kondo scattering in elctronic-transport measurements, providing evidence for the formation of magnetic moments. The origin of magnetism is attributed to cation (Ti) vacancies, confirmed by X-ray absorption spectroscopy and first-principle calculations. The Ti vacancies are controlled by oxygen partial pressure during growth. [source]

    Digital photography: A primer for pathologists

    Roger S. Riley
    Abstract The computer and the digital camera provide a unique means for improving hematology education, research, and patient service. High quality photographic images of gross specimens can be rapidly and conveniently acquired with a high-resolution digital camera, and specialized digital cameras have been developed for photomicroscopy. Digital cameras utilize charge-coupled devices (CCD) or Complementary Metal Oxide Semiconductor (CMOS) image sensors to measure light energy and additional circuitry to convert the measured information into a digital signal. Since digital cameras do not utilize photographic film, images are immediately available for incorporation into web sites or digital publications, printing, transfer to other individuals by email, or other applications. Several excellent digital still cameras are now available for less than $2,500 that capture high quality images comprised of more than 6 megapixels. These images are essentially indistinguishable from conventional film images when viewed on a quality color monitor or printed on a quality color or black and white printer at sizes up to 11×14 inches. Several recent dedicated digital photomicroscopy cameras provide an ultrahigh quality image output of more than 12 megapixels and have low noise circuit designs permitting the direct capture of darkfield and fluorescence images. There are many applications of digital images of pathologic specimens. Since pathology is a visual science, the inclusion of quality digital images into lectures, teaching handouts, and electronic documents is essential. A few institutions have gone beyond the basic application of digital images to developing large electronic hematology atlases, animated, audio-enhanced learning experiences, multidisciplinary Internet conferences, and other innovative applications. Digital images of single microscopic fields (single frame images) are the most widely utilized in hematology education at this time, but single images of many adjacent microscopic fields can be stitched together to prepare "zoomable" panoramas that encompass a large part of a microscope slide and closely simulate observation through a real microscope. With further advances in computer speed and Internet streaming technology, the virtual microscope could easily replace the real microscope in pathology education. Later in this decade, interactive immersive computer experiences may completely revolutionize hematology education and make the conventional lecture and laboratory format obsolete. Patient care is enhanced by the transmission of digital images to other individuals for consultation and education, and by the inclusion of these images in patient care documents. In research laboratories, digital cameras are widely used to document experimental results and to obtain experimental data. J. Clin. Lab. Anal. 18:91,128, 2004. © 2004 Wiley-Liss, Inc. [source]

    Photocatalytic Water Splitting with the Cr-Doped Ba2In2O5/In2O3 Composite Oxide Semiconductors.

    CHEMINFORM, Issue 38 2005
    Defa Wang
    Abstract For Abstract see ChemInform Abstract in Full Text. [source]

    Doping of the Metal Oxide Nanostructure and its Influence in Organic Electronics

    Mi-Hyae Park
    Abstract Synthesizing metal oxides through the sol,gel process provides a convenient way for forming a nanostructured layer in wide band gap semiconductors. In this paper, a unique method of introducing dopants into the metal oxide semiconductor is presented. The doped TiO2 is prepared by adding a Cs2CO3 solution to a nanocrystalline TiO2 solution that is synthesized via a non-hydrolytic sol,gel process. The properties of the TiO2:Cs layer are investigated and the results show stable nanostructure morphology. In addition to providing morphological stability, Cs in TiO2 also gives rise to a more desirable work function for charge transport in organic electronics. Polymer solar cells based on the poly(3-hexylthiophene) (P3HT): methanofullerene (PC70BM) system with the addition of a TiO2:Cs interfacial layer exhibit excellent characteristics with a power conversion efficiency of up to 4.2%. The improved device performance is attributed to an improved polymer/metal contact, more efficient electron extraction, and better hole blocking properties. The effectiveness of this unique functionality also extends to polymer light emitting devices, where a lower driving voltage, improved efficiency, and extended lifetime are demonstrated. [source]

    Cover Picture: Fabrication of Multicomponent Microsystems by Directed Three-Dimensional Self-Assembly (Adv. Funct.

    Abstract Directed three-dimensional self-assembly to assemble and package integrated semiconductor devices is demonstrated by Jacobs and Zheng on p.,732. The self-assembly process uses geometrical shape recognition to identify different components and surface-tension between liquid solder and metal-coated areas to form mechanical and electrical connections. The components (top left) self-assemble in a turbulent flow (center) and form functional multi-component microsystems (bottom right) by sequentially adding parts to the assembly solution. The technique provides, for the first time, a route to enable the realization of three-dimensional heterogeneous microsystems that contain non-identical parts, and connecting them electrically. We have developed a directed self-assembly process for the fabrication of three-dimensional (3D) microsystems that contain non-identical parts and a statistical model that relates the process yield to the process parameters. The self-assembly process uses geometric-shape recognition to identify different components, and surface tension between liquid solder and metal-coated areas to form mechanical and electrical connections. The concept is used to realize self-packaging microsystems that contain non-identical subunits. To enable the realization of microsystems that contain more than two non-identical subunits, sequential self-assembly is introduced, a process that is similar to the formation of heterodimers, heterotrimers, and higher aggregates found in nature, chemistry, and chemical biology. The self-assembly of three-component assemblies is demonstrated by sequentially adding device segments to the assembly solution including two hundred micrometer-sized light-emitting diodes (LEDs) and complementary metal oxide semiconductor (CMOS) integrated circuits. Six hundred AlGaInP/GaAs LED segments self-assembled onto device carriers in two minutes, without defects, and encapsulation units self-assembled onto the LED-carrier assemblies to form a 3D circuit path to operate the final device. The self-assembly process is a well-defined statistical process. The process follows a first-order, non-linear differential equation. The presented model relates the progression of the self-assembly and yield with the process parameters,component population and capture probability,that are defined by the agitation and the component design. [source]

    Patterning and Templating for Nanoelectronics

    ADVANCED MATERIALS, Issue 6 2010
    Kosmas Galatsis
    Abstract The semiconductor industry will soon be launching 32,nm complementary metal oxide semiconductor (CMOS) technology node using 193,nm lithography patterning technology to fabricate microprocessors with more than 2 billion transistors. To ensure the survival of Moore's law, alternative patterning techniques that offer advantages beyond conventional top-down patterning are aggressively being explored. It is evident that most alternative patterning techniques may not offer compelling advantages to succeed conventional top-down lithography for silicon integrated circuits, but alternative approaches may well indeed offer functional advantages in realising next-generation information processing nanoarchitectures such as those based on cellular, bioinsipired, magnetic dot logic, and crossbar schemes. This paper highlights and evaluates some patterning methods from the Center on Functional Engineered Nano Architectonics in Los Angeles and discusses key benchmarking criteria with respect to CMOS scaling. [source]

    Fullerene Sensitized Silicon for Near- to Mid-Infrared Light Detection

    ADVANCED MATERIALS, Issue 5 2010
    Gebhard J. Matt
    A novel light-sensing scheme based on a silicon/fullerene-derivative heterojunction allows optoelectronic detection in the near- to mid-infrared (IR), which is fully compatible with complementary metal oxide semiconductor (CMOS) technology. Although silicon and the fullerene derivative do not absorb in the IR, a heterojunction of these materials absorbs and generates a photocurrent (PC) in the near- to mid-IR, presumably caused by an interfacial absorption mechanism. [source]

    Controlled Growth of High-Quality ZnO-Based Films and Fabrication of Visible-Blind and Solar-Blind Ultra-Violet Detectors

    ADVANCED MATERIALS, Issue 45 2009
    Xiaolong Du
    Abstract ZnO is a wide-bandgap (3.37,eV at room temperature) oxide semiconductor that is attractive for its great potential in short-wavelength optoelectronic devices, in which high quality films and heterostructures are essential for high performance. In this study, controlled growth of ZnO-based thin films and heterostructures by molecular beam epitaxy (MBE) is demonstrated on different substrates with emphasis on interface engineering. It is revealed that ultrathin AlN or MgO interfacial layers play a key role in establishing structural and chemical compatibility between ZnO and substrates. Furthermore, a quasi-homo buffer is introduced prior to growth of a wurtzite MgZnO epilayer to suppress the phase segregation of rock-salt MgO, achieving wide-range bandgap tuning from 3.3 to 4.55,eV. Finally, a visible-blind UV detector exploiting a double heterojunction of n-ZnO/insulator-MgO/p-Si and a solar-blind UV detector using MgZnO as an active layer are fabricated by using the growth techniques discussed here. [source]

    Particle surface temperature measurements with multicolor band pyrometry

    AICHE JOURNAL, Issue 1 2009
    Hong Lu
    Abstract A noncontact, color-band pyrometer, based on widely available, inexpensive digital imaging devices, such as commercial color cameras, and capable of pixel-by-pixel resolution of particle-surface temperature and emissivity is demonstrated and described. This diagnostic instrument is ideally suited to many combustion environments. The devices used in this method include color charge-coupled device (CCD), or complementary metal oxide semiconductor (CMOS) digital camera, or any other color-rendering camera. The color camera provides spectrally resolved light intensity data of the image, most commonly for three color bands (Red, Green, and Blue,), but in some cases for four or more bands or for a different set of colors. The CCD or CMOS sensor-mask combination has a specific spectral response curve for each of these color bands that spans the visible and often near infrared spectral range. A theory is developed, based on radiative heat transfer and camera responsivity that allows quantitative surface temperature distribution calculation, based on a photograph of an object in emitted light. Particle surface temperature calculation is corrected by heat transfer analysis with reflection between the particle and reactor wall for particles located in furnace environments, but such corrections lead to useful results only when the particle temperature is near or below the wall temperatures. Wood particle-surface temperatures were measured with this color-band pyrometry during pyrolysis and combustion processes, which agree well with thermocouple measured data. Particle-surface temperature data simultaneously measured from three orthogonal directions were also mapped onto the surface of a computer generated 3-D (three-dimensional) particle model. © 2008 American Institute of Chemical Engineers AIChE J, 2009 [source]

    Non-enzymatic aqueous peroxyoxalate chemiluminescence immune detection using a CCD camera and a CMOS device

    Brian Filanoski
    Abstract A new method for non-enzymatic aqueous peroxyoxalate chemiluminescence (POCL) biomolecular detection using imaging chip-based devices has been developed. A water-soluble amide of oxalic acid was synthesized and used in the investigation and characterization of POCL immunodetection in an aqueous environment. Six fluorescent dyes commonly used in biological detection were tested, and the intensity of light generated from the aqueous POCL reactions was characterized in the liquid phase. Direct detection sensitivity comparisons between a standard fluorescent method and this POCL method were performed in both liquid and solid phases. Results showed that detection sensitivity using the POCL method is comparable to that of the fluorescent method. POCL biomolecular detection on a nitrocellulose membrane was also investigated using a charge-coupled device (CCD) camera. Again, POCL detection sensitivity proved to be comparable to that using the fluorescent detection method. In an application of aqueous POCL biomolecular detection, Staphylococcus aureus enterotoxin B (SEB) and its antibody were used to demonstrate immuno- and affinity detection. For further applications, such as DNA and protein arrays, simultaneous detection of biomolecules labelled with different fluorescent labels was investigated, using a complementary metal oxide semiconductor (CMOS) colour imaging chip. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Clustering behaviour in gas,liquid,solid circulating fluidized beds with low solid holdups of resin particles

    Jianhua Liu
    Abstract The flow in a gas,liquid,solid circulating fluidized bed is self-organised and manifests itself with clustering of particles and bubbles. The clustering behaviour in the fluidized bed at low solid holdups of resin particles was experimentally investigated with a high-speed image measurement and treatment technique of complementary metal oxide semiconductor to enhance the fundamental understanding on such a flow. Several new physical quantities were suggested to characterise such ordered flow structures. The main findings are as follows. The clusters of solid particles largely exist as doublets and triplets, the mixed groups of particles and bubbles mostly exist as one bubble carrying two to four particles. Increasing superficial liquid velocity, particle diameter or density weakens the aggregation degrees of both particle and mixed clusters in the riser and downer, except that the increase of superficial liquid velocity enhances the mixed clustering behaviour in the riser. The climbing of the auxiliary liquid velocity or liquid phase viscosity intensifies the aggregation behaviour, except that the increase of liquid phase viscosity reduces the mixed clustering degree in the riser. The influences of superficial gas velocity and surface tension of liquid phase on the clustering behaviour seem to be a little complex and the trends are not simply increasing or decreasing. The life cycle of solid particle clusters in the GLS riser is not sensitive to the operation conditions, being around 0.07,s. The mixed clusters' life cycle is more sensitive to the conditions and physical properties of phases, changing from 0.02 to 0.07,s. L'écoulement dans un lit fluidisé de circulation gaz-liquide-solide s'organise souvent de lui même et se manifeste avec l'agrégation des particules et des bulles. Le comportement de l'agrégation dans le lit fluidisé à faible retenue de particules de résine solide a été étudié expérimentalement en utilisant une technique d'imagerie ultra-rapide de mesure et de traitement à base de semi-conducteur complémentaire à l'oxyde de métal afin d'approfondir la compréhension fondamentale d'un tel écoulement. Plusieurs nouvelles quantités physiques ont été suggérées pour caractériser une telle structure d'écoulement auto-organisé. Les principaux résultats sont comme suit. Les agrégations de particules solides existent principalement en tant que doublets et triplets, les groupes mixtes de particules et de bulles existent pour la plupart sous la forme d'une bulle comportant deux à quatre particules. Une augmentation de la vitesse superficielle du liquide, du diamètre des particules ou de la densité affaiblit à la fois les degrés d'agrégation des particules et des agrégats mixtes dans la colonne montante et dans la colonne descendante, sauf que l'augmentation de la vitesse superficielle du liquide intensifie le comportement d'agrégation mixte dans la colonne montante. L'accroissement de la vitesse auxiliaire du liquide ou de la viscosité de la phase liquide intensifie le comportement d'agrégation, sauf que l'augmentation de la viscosité de la phase liquide réduit le degré d'agrégation mixte dans la colonne montante. Les influences de la vitesse superficielle du gaz et de la tension de surface de la phase liquide sur le comportement de l'agrégation semblent être quelque peu complexes et les tendances ne sont pas simplement croissantes ou décroissantes. Le cycle de vie des agrégats de particules solides dans la colonne gaz-liquide-solide montante n'est pas sensible aux facteurs, tournant autour de 0.07,s. Le cycle de vie des agrégats mixtes est plus sensible aux conditions de fonctionnement et aux caractéristiques physiques des phases, évoluant de 0.02 à 0.07,s. [source]

    Molecular and biomolecular interfaces to metal oxide semiconductors

    Robert J. Hamers
    Abstract Previous work has shown that organic alkenes will graft to covalent semiconductors such as diamond and silicon. Here, we demonstrate that organic alkenes can be grafted to the surfaces of metal oxide semiconductors, including TiO2 in nanocrystalline thin films and as single-crystal anatase(001) epitaxial films grown on SrTiO3(001) substrates. The resulting layers can be used as a starting point for linking biomolecules such as DNA to metal oxide surfaces. Initial results are presented showing that this chemistry can also be applied to graft molecular layers to zirconium oxide thin films. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Organic Polyaromatic Hydrocarbons as Sensitizing Model Dyes for Semiconductor Nanoparticles

    Yongyi Zhang
    Abstract The study of interfacial charge-transfer processes (sensitization) of a dye bound to large-bandgap nanostructured metal oxide semiconductors, including TiO2, ZnO, and SnO2, is continuing to attract interest in various areas of renewable energy, especially for the development of dye-sensitized solar cells (DSSCs). The scope of this Review is to describe how selected model sensitizers prepared from organic polyaromatic hydrocarbons have been used over the past 15 years to elucidate, through a variety of techniques, fundamental aspects of heterogeneous charge transfer at the surface of a semiconductor. This Review does not focus on the most recent or efficient dyes, but rather on how model dyes prepared from aromatic hydrocarbons have been used, over time, in key fundamental studies of heterogeneous charge transfer. In particular, we describe model chromophores prepared from anthracene, pyrene, perylene, and azulene. As the level of complexity of the model dye-bridge-anchor group compounds has increased, the understanding of some aspects of very complex charge transfer events has improved. The knowledge acquired from the study of the described model dyes is of importance not only for DSSC development but also to other fields of science for which electronic processes at the molecule/semiconductor interface are relevant. [source]