In this proceeding, we discuss measurements of the vibrational properties of hydrides using inelastic neutron scattering (INS) and the impact of the vibrational modes on the thermodynamic properties. We compare the heat capacity of PdH0.63 and LiBH4 as measured calorimetrically to that derived form INS spectra. We show that the vibrational properties of Ca(BH4)2 depend on the specific phase and hitherto determine their stability.

Polyelectrolyte (PE) gels exhibit complex phase behavior that includes the existence of nanostructures in poor-solvent conditions. The formation of these inhomogeneous structures is made possible by the competition between the short-range hydrophobic, elastic, and entropic interactions and the long-range electrostatic forces. We develop a theoretical framework that describes the effect of monomer and charge inhomogeneities in PE gels. Numerical calculations performed on a salt-free PE gel with one-dimensional heterogeneities demonstrate the presence of nanophases for a finite range of physical parameters.

SiC-fiber-reinforced TiAl composites (SiC/TiAl) have attractive attention due to their potential for replacing titanium and nickel-base alloys in aerospace systems such as advanced turbine engines and hypersonic vehicles where specific strength and stiffness at high temperature are critical. The interface layers of SiC/TiAl are believed to contribute strongly to its mechanical properties. A variety of interface modification, such as C, BN, W, and/or Mo coatings has been applied to the fiber to produce composites, together with the identification of several new interface modification systems, showing promise for high-performance fibers and improved composite properties. A research from a perfect cross-sectional view to get more direct and reliable interfacial information especially about bonding around the fiber circumference, has been limited partly due to the difficulty of preparing suitably thin TEM specimen without damaging the interface layers. We report our preparation method for a perfect cross-sectional TEM specimen of SiC/TiAl and the interface characterization results.

Single SiC-based Si-Ti-C-O fiber (SiTiC) ˜13 μm in diameter containing about 2% Ti to improve its thermal stability has been used as a reinforcement. Chemical or physical vapor deposition has been used to deposit C or TiAl layer. C layer has been deposited-uniformly around the fiber at a thickness of about 100 nm and TiAl coating at about 1400 nm. C layer consisted of large amounts of micro crystals of about 1-30 nm accumulated around the interface of C layer and fiber. TiAl layer consisted of crystals of about 60-360nm.

The specimen has been annealed at 1173 K for 2 hrs in Ar, and prepared by sandwiching and 3mm disks obtained by ultrasonic drilling and mechanical-polishing to ∼100 μm. Those disks have been further ground by a dimpler to ∼10 μm, and argon-ion-milling to get an electron-beam-transparent foil. H-9000UHR II TEM operating at 300 kV, equipped with EDX (prove 1nm) has been used.

Interfacial reaction and diffusion mainly occurred in the interface between the C layer and SiTiC fiber and the C and TiAl layers. No direct reaction or diffusion occurred between the SiTiC fiber and TiAl layer. Small amounts of needle-like compound assigned as Aluminum Titanium Carbide, (Ti3AlC)5C, propagating into the fiber has been found at the interface area. These compounds consist of C, Si, O, Ti, and Al, indicating they are reaction and diffusion products of SiTiC fiber and TiAl. Such Aluminum Titanium Carbide propagating into the fiber seems to induce new stress concentration and generate new crack in the fiber and degrade the fiber and the composite strength. Combined with the tensile testing of SiTiC/TiAl single fiber reinforced composites reported previously, we surmise that the large amounts of small crystals accumulating in the C layer contribute to resistance to interfacial reaction and diffusion between the fiber and TiAl layer.

We evaluated Triangular Voltage Sweep (TVS) measurements as a technique to characterize plasma damage in low-k films. Blanket wafers with low-k films of different porosity and k value were prepared. Our samples included an SiOC:H material with 7% porosity and k value of 3.0, deposited on 200mm wafers, and two SiOC:H materials with 25% porosity and k value of 2.5, deposited on 300mm wafers. Before deposition, a thin layer of dry thermal oxide (2 – 5 nm) was grown on the n-type wafers to stabilize the silicon interface. After deposition, low-k films were exposed to N2/H2 plasma for different times in order to induce different degree of plasma damage. Untreated low-k films were always included as a reference. For electrical measurements, metal dots were deposited on pieces to fabricate Metal-Insulator-Semiconductor capacitors.

TVS measurements were performed at 190°C on the different samples. On samples exposed to N2/H2 plasma, we detected a current peak in the TVS trace, whose magnitude increased with exposure time to plasma. No peaks were detected on untreated films. This indicates that TVS measurements are sensitive to plasma damage. Furthermore, TVS results correlated well with FTIR spectra that showed increasing damage and H2O uptake with increasing exposure time to plasma. We conclude that TVS measurements are suitable for characterizing the degree of plasma damage in low-k films and complement well materials analysis, because with the help of TVS a link to leakage properties can be made. As an application, we used TVS measurements for evaluating restoration of plasma damaged low-k films by long N2-bake at high temperature. Wafer pieces from each sample were baked at 350°C for 4h30min in N2 atmosphere. A few pieces were measured immediately after baking. The remaining pieces were either left exposed to ambient for a few days or dipped in deionized H2O for a few hours to evaluate recovery of hydrophobic properties. The different treatments (N2-bake, exposure to ambient, H2O dipping) were always performed on blanket wafer pieces. Metal dots for electrical measurements were only deposited after the treatment. CV and FTIR measurements were performed before and after treatments to evaluate change in k-value and material structure, respectively. Our data show that long N2-bake at high temperature can partially restore damaged low-k films. The magnitude of the damage-related TVS peak was significantly reduced after heat treatment and remained stable even after H2O dipping. CV measurements performed on baked pieces after 6 days of exposure to ambient showed a reduced k-value. Consistently, FTIR spectra showed a significant reduction of H2O content soon after baking. The materials remained stable over several days and only minor reincorporation of H2O occurred after exposure to ambient or H2O dipping. Therefore, long N2-bake at high temperature can partially restore leakage (TVS), k-value (CV) and hydrophobic properties (FTIR) of damaged low-k films.

Assessment of anodic and cathodic potentials on stress corrosion cracking (SCC) of API X52 pipeline steel through slow strain rate tests (SSRT) was studied. The SSRT were carried out in a NS4 solution to simulated dilute ground water that has been found to be associated with SCC of pipelines. SSRT were performed and evaluated in air and in the NS4 solution at room temperature at an extension rate of 1×10-6 in/sec. Tests were performed at controlled electrochemical polarization potentials, both anodic and cathodic (100, 200, 400 mV) versus the open circuit corrosion potential. The results of reduction in area ratio (RAR), time to failure ratio (TFR) and plastic elongation ratio (PER) of the specimens tested in the soil solution indicate that X52 pipeline steel was susceptible to SCC at cathodic potentials. These specimens showed a brittle type of fracture with transgranular appearance. The SCC proceess and mechanism of X52 steel in the NS4 solution is mixed-controlled by both anodic dissolution and the hydrogen involvement. At positive potentials the SCC is based mainly on the anodic dissolution mechanism. When the applied potentials shifted negatively, the SCC on the steel follows mainly hydrogen embrittlement mechanism. This mechanism was confirmed through the internal cracks observed in the specimens.

We propose a novel method for self-assembled packing of silica microsphere in micro-channel which can be potentially used for on-chip chromatography. Chromatography has been one of the most widely used techniques for the analysis and separation of the mixtures of biochemical compounds in research laboratories and industrial factories. Numerous chromatography techniques such as High-Performance Liquid Chromatography (HPLC), Thin Layer Chromatography (TLC) use absorbents (ex: silica, alumina, cellulose) as stationary phase material [1]. Effective loading of absorbents in those techniques has been a huge challenge since it requires additional implementation of high-pressure pump system (for HPLC) or limits selective coating of absorbents on supporting plate (for TLC). In order for chromatography to be efficiently integrated with micro-fluidic Lab-on-a-chip devices, novel techniques for easy and simple packing of absorbents within micro channels should be developed.

Solvent-evaporation based 2-D crystallization technique [2] can enable mono-dispersed micro-particles to be self-assembled by capillary attractive forces. We apply this technique to assemble dense packing of silica microsphere and form ultra thin layers (2˜3 layers) within open microchannel. Open micro-channel has been constructed by conventional photolithography of SU8 photoresist. A small droplet (Volume: 0.1μL) of silica suspension (Diameter: 3μm, Solvent: DI Water, Concentration: 1.25wt%) has been placed in the defined inlet of micro channel. Capillary force within the open SU8 microchannel induces the flow of silica suspension in the channel. The packing of microsphere starts from the outlet side of the channel, where the thickness of solvent drastically decreases due to sudden increase of cross-sectional area of channel, and this packing propagates to the inlet side of the channel until solvent evaporates completely. As a result, a dense packing of silica microspheres are successfully assembled and a thin layer of silica microspheres are formed within open micro-channel.

We will present the characterization of silica packing with regard to various process parameters and also will include theoretical interpretation of this packing technique in more detail. We will also present our future approach to integrate our technique on-chip chromatography applications.

Aculon, Inc. specializes in inventing and commercializing unique molecular-scale surface and interfacial coatings leveraging nanotechnology discoveries made at Princeton University. These coatings can be classified into three functional areas; non-stick, pro-stick/adhesion, and anti-corrosion.The company has formulated coating solutions and processes for numerous markets including optical, display, electronics, consumer products and industrial coatings. These specialized coatings outperform all known alternatives in characteristics such as adhesion, stain resistance, and scratch resistance.Fueling the company’s commercialization efforts are its proprietary Self-Assembled Monolayer of Phosphonates (SAMP) technology. The commercialization of SAMP treatments can be used for a variety of applications including imparting hydrophobicity, adhesion, or corrosion inhibition to numerous substrates.For surface treatments to be effective, they must be mechanically and chemically stable under conditions experienced in the intended area of use. Aculon’s proprietary Self-Assembled Monolayer of Phosphonates methodology can impart any of these properties as desired to metals, metal oxides and even some polymer surfaces by drawing on its library of structurally tailored phosphonic acids.The secret to the commercialization is covalent bonding, which creates a uniquely strong attachment between the SAMP and the substrate. Because the SAMP is one approximately 1.5 nm thick, it completely covers the material to which it is applied, and assures total surface coverage regardless of the type or texture of that material. The composition of the SAMP determines the properties that it imparts to its substrate.In 1998, Professor Jeffery Schwartz of Princeton University discovered that well-ordered monolayers of phosphonates could be formed by self-assembly on a wide variety of oxide and oxide-terminated surfaces. At that time Professor Schwartz and his team also discovered that a simple dip process enabled SAMP formation on substrates of complex structures and geometries, as well as traditionally “unreactive” surfaces.The research showed that SAMP adhesion to oxides was mechanically strong and resisted removal by hydrolysis and oxidation. It showed further that by using the dip method, SAMPs of a variety of molecular structures, including aliphatic, aromatic, and heteroaromatic, could be prepared.Commercialization of SAMPs proves that such surface-bound phosphonates can dictate control of the surface properties of myriad substrates and that they can be implemented using well-known industrial techniques and conditions. These processes can be scaled to meet the needs of large or small facilities, and can be applied to surfaces of nearly any size or shape without special needs. Based on the needs of the producer, surface modification can be completed during the time of manufacturing or can be performed as a post-production step.

Extracted samples of L3 vertebrae, the healthy, osteopenic and osteoporotic from Mexican men, were fixed to carry out measurements of the modulus of elasticity (ME) and the minerals content, on the trabecular zone to study their behavior as a function of age.

To determine the ME the immersion ultrasonic method (IUM) was used, X-ray dispersion was applied to know the chemical element concentration (Ca++, Na++, P, and Mg++) and computerized axial tomography (CAT) to obtain bone mineral density (BMD).The samples were organized in four groups by decade. The samples in the range of 30-39 years revealed: a normal BMD and a concentration [% w/w] between pairs of Ca++/P, Ca++/Mg++, P/Mg++ and Mg++/ Na ++ with correlation positive due to the strong dependence between them.

The average ME results were: 2.79±0.326, 2.68±0.45, 2.66±0.43 and 2.70±0.397 [GPa] for each decade respectively. The ME profiles show a nonlinear behavior as a function of age, indicating a minimum value in the third decade, similar behavior is observed in the Ca++. An exponential behavior between ME and T-score was obtained. The plotted Ca++ and ME as a function of area showed a homogeneous distribution for the first and a non homogeneous for the second.

Integration of the III–V channel MISFETs on the Si platform is a potential solution to realize performance improvement and power reduction in the sub-22 nm node and beyond. To take advantage of the high electron mobility of III-Vs, the MIS interfaces of high integrity should be developed. This paper reports how the MIS characteristics vary in response to the changes in the interface composition and structures, and discusses the physics and chemistry behind these observations. We fabricated a wide variety of the high-k/III–V interface structures by employing the state-of-the-art technologies of the epitaxial wafers by MOCVD, surface reconstruction control in the MBE environment, wet/dry surface treatments optimized by utilizing XPS/AES analyses, and deposition of quality dielectrics (Al2O3, HfO2) by ALD and EB evaporation. The MIS characteristics were evaluated in the capacitor and FET structures. The talk will include the following topics: the effects of the cation composition (Al, Ga, In) of the III-V bulk on the MIS characteristics [1], the importance of the anion control (N, S) at the interface to improve the MIS characteristics, and the surface orientation ((100) vs. (111)) as a new parameter in the III-V MIS device design [1]. This work was carried out in the Nanoelectronics Project supported by NEDO/METI. [1] T. Yasuda et al., as discussed at 39th IEEE SISC (San Diego, Dec. 2008).

The synthesis of ceria nanoparticles using an inverse microemulsion technique and precipitation method was investigated. Ceria nanoparticles were synthesized by adding diluted ammonia to a microemulsion consisting of n-heptane, Marlophen NP5 and cerium nitrate. The micelle and particle size were adjustable in the range of 5-12nm by varying the molar ratio of water to surfactant and analyzed by dynamic light scattering (DLS), small angle X-ray scattering (SAXS) and high-resolution transmission electron microscopy (HRTEM). After isolation through precipitation, the nanoparticles were subsequently treated at 100-600 °C. The catalytic activity of particles annealed at 400 and 600 °C were tested in soot combustion reactions and characterized by temperature-programmed oxidation (TPO) indicating a size-dependant activity. To prevent the nanoparticles from aggregation, the microemulsion technique was adopted to integrate the nanoparticles homogeneously into a mesoporous SiC matrix through the use of a preceramic polymer. The obtained composite material was also tested in soot combustion reactions.

Silver sulfide (Ag2S) and cadmium sulfide (CdS) nanoparticles of adjustable sizes are synthesized using a water-in-hexane microemulsion method and stabilized by dodecanethiol. The stabilized metal sulfide nanoparticles can be deposited homogenously on flat substrates forming ordered 2D arrays in supercritical fluid carbon dioxide (Sc-CO2). The use of Sc-CO2 leaves the particles unaffected by de-wetting effects and surface tension caused by traditional solvents and produces uniform arrays. The Sc-CO2 deposition technique can effectively fill the metal sulfide nanoparticles into nanoscale features, which is difficult to achieve by conventional solvent evaporation methods.

Hydrogenated amorphous silicon (a-Si:H) was deposited with the Expanding Thermal Plasma-CVD (ETP CVD) method utilizing pulse-shaped substrate biasing to induce controlled ion bombardment during film growth. The films are analyzed with in-situ real time spectroscopic ellispometry, FTIR spectroscopy, as well as reflection-transmission and Fourier transform photocurrent spectroscopy (FTPS) measurements. The aim of this work is to investigate the effect ion bombardment with well defined energy on the roughness evolution of the film and the material properties.

We observe two separate energy regimes with material densification and relatively constant defect density below ˜ 120-130 eV and a constant material density at increasing defect density > 120-130 eV substrate bias. We discuss our results in terms of possible ion – surface atom interactions and relate our observations to reports in literature.

The field of major applications of transparent conducting oxides (TCOs) continues to expand, thus generating a growing demand for new materials with lower resistivity and higher transparency over extended wavelength ranges. Moreover, p-type TCOs are opening new horizons for high-performance devices based on p-n junctions.Among the most commonly used TCO materials are zinc oxide (ZnO), indium tin oxide (ITO), tin oxide (SnO2), and indium oxide (In2O3). Still, design and synthesis of improved TCO materials leading to a marked increase in conductivity and robustness remain highly desirable while a more detailed understanding of the conductivity mechanisms is critical to further improvement. For example, there is an accelerating effort worldwide by both academia and industry to develop a transparent conductor that can meet or beat the performance of the commonly used ITO at lower costs and with more physical resilience.This article reviews new developments in TCO materials to be used in various applications spanning from photovoltaics to lighting, smart windows, or gas sensors. The financial stakes, far from being negligible in the TCOs market, and the current scientific and technological challenges to be taken up are analyzed.

Understanding thermal transport between carbon nanotubes (CNTs) and dielectric substrates is important both for nanoscale thermal management and CNT device applications. We investi-gate thermal transport between a (10,10) CNT and an SiO2 substrate through non-equilibrium classical molecular dynamics (MD) simulations. The thermal boundary conductance (TBC) is computed by setting up a temperature pulse in the CNT and monitoring its relaxation. The TBC is found to scale nearly linearly with temperature between 200�600 K, where a quantum correction is applied to the CNT heat capacity through its phonon density of states. However, the TBC ap-pears most sensitive to the strength the CNT-substrate interaction, which linearly modulates it between 0.05�0.30 WK-1m-1, in the range suggested by recent experimental data.

ZnO nanowires with strong green emission synthesized by chemical vapor deposition were treated using hydrogen plasma. The effect of hydrogen plasma treatment was studied by means of photoluminescence and photoconductivity. A strong passivation of the green emission and a significant enhancement of the near band edge emission were found after the hydrogen plasma treatment. The conductivity of the nanowires in dark was increased by more than 3 orders of magnitude. The photoconductivity also increased after the hydrogen plasma treatment. The observed changes in the luminescence and photoconductive properties of the ZnO nanowires were likely caused by hydrogen atoms occupying both oxygen vacancies and interstitial sites.

We report on the photoluminescence (PL) of GaAs-Al0.32Ga0.68As core-shell nanowires grown by MOVPE, and their dependence on the precursors V:III molar ratio utilised in the vapor during growth. It is shown that the PL emission of the GaAs nanowire core red-shifts with decreasing the V:III ratio from 30:1 to 4:1, an effect tentatively ascribed to the build-up of a space-charge region at the core-shell hetero-interface, the latter associated to the unintentional incorporation of impurities, namely C in GaAs and Si in AlGaAs.

As the use of sensor networks has expanded, the demand for robust detectors able to operate in a variety of environments has grown. We present the sensitivity testing of a micro thermal conductivity detector (μTCD) operating in two different modes. The microfabricated device we have designed and tested is composed of a resistive heating element suspended in a micro-channel, which creates excellent thermal isolation and a high heat transfer coefficient between the element and the fluid. The sensitivity of a μTCD integrated into a micro-gas chromatography (GC) system, can be increased by a factor of 10 simply by switching between operation in constant temperature and constant voltage modes. This result agrees with the analytical models and testing data previously reported for macro systems and devices.

Water soluble poly(4-styrenesulfonic acid-co-maleic acid), PSSA-co-MA, stabilized nickel(0) and cobalt(0) nanoclusters were prepared for the first time from the reduction of nickel(II) chloride and cobalt(II) chloride by using minimum amount of sodium borohydride shortly before their usage as catalysts in the hydrolysis of ammonia-borane (AB) in the same medium at room temperature. PSSA-co-MA stabilized nickel(0) and cobalt(0) nanoclusters showed high catalytic activity in hydrogen generation from the hydrolysis of AB even at low temperature.

Aluminium-doped zinc oxide (ZnO) films have been prepared by spray pyrolysis technique using the mixed solution of zinc acetate dihydrate and aluminium nitrate nonahydrate in methanol. Concentration of aluminum in the solution was varied in a range of 1, 3 and 5 atomic percents. The results from X-ray diffraction showed that the preferred orientation of ZnO films changed to the [002] direction when the concentration of aluminum in the solution exceeded 1 atomic percents. ZnO films deposited from the 3 atomic percent Al containing solution had the largest grains and showed the lowest resistivity of 75 Ω-cm. Addition of aluminum into the precursor solution shifted the absorption edge towards longer wavelengths.

Ventilator associated pneumonia (VAP) is a serious and costly clinical problem. Specifically, receiving mechanical ventilation over 24 hours increases the risk of VAP and is associated with high morbidity, mortality and medical costs. This complication is especially hard to diagnose in children because of non-specific clinical signs and lack of established diagnostic methods.Cost effective endotracheal tubes (ETTs) that are resistant to bacterial infection would be essential tools for the prevention of VAP.In addition to their bacterial resistance, ETT with magnetic nanoparticles could aid in the diagnosis of VAP allowing physicians to locate infections with greater accuracy.The objective of this study was twofold, first to develop strategies to decrease bacterial adhesion on nano-rough ETT and secondly to develop better methods to assess in vitro bacterial adhesion or biofilm formation on ETT. In preliminary tests, nanomodified polyvinyl chloride (PVC) ETTs has been shown to be effective at reducing bacterial colonization. This study also sought to evaluate the bacterial resistance of these ETTs more effectively by creating a bench top airway model, which can create a similar environment to the flow system that ETTs are exposed to in vivo. The airway model designed to test ETTs has two Plexiglas chambers representing the oropharynx and the lungs, a tube representing the trachea and finally an intricate pumping system to the oropharynx with bacteria flow and to the lung with simulated compliance and resistance. ETTs were connected to a ventilator and passing the oropharynx into the trachea and observed under the mechanical ventilation and continuous bacterial flow system.In addition, the study examined dual gas flow conditions and their effect on bacterial growth of ETT.In no less than three separate trials in the airway chamber, each ETT will be tested for its effectiveness at the reduction of bacterial growth within the airway by sampling from both lung and oropharynx chambers during continuous operation.Special attention will be given to the long-term effects on the ETT by including a study that lasts longer than ten days. Both the bacterial proliferation in the two chambers and on the ETT itself will be carefully analyzed. This specialized testing should yield valuable information on the efficacy of nanomodified ETT in airway conditions and will provide further evidence to determine if nanomodified ETTs are a valid solution to VAP.