Metallic silver nanoparticles (NPs) have extensively been used in the treatment of disease and purification and heralded the ‘first wave’ of disinfection science, the ‘second wave’ being the nanocomposite of metal-doped TiO2. Recent advances in engineered surfaces have enabled ultrahigh surface area and rapid sterilization via using metal-organic frameworks (MOFs) as the ‘third wave’ disinfectant. MOFs offer the same advantages as colloids but also have ultra high surface area, long term persistence and ultra low doses, applied for water purification.

Highly ion-conductive Li6PS5Cl Li-argyrodites were prepared through a high energy ball milling. Electrical and electrochemical properties were investigated. Ball-milled compounds exhibit a high conductivity of 1.33×10−4 S/cm with an activation energy of 0.3-0.4 eV and an electrochemical stability up to 7V vs. lithium. These results are obtained after only 10 hours of milling and with no additional heat treatment.

To validate the use of the Li6PS5Cl-based solid electrolyte, all-solid-state batteries using LiCoO2 and Li4Ti5O12 as active material have been realized. The optimization of the electrode composition led to a maximum of 46 and 27 mAh per gram of composite for LiCoO2 and Li4Ti5O12-based half-cells respectively. The assembled all-solid-state LiCoO2 / Li6PS5Cl / Li4Ti5O12 battery presents a sustainable reversible capacity of 27 mAh per gram of active material and a coulomb efficiency close to 99%.

As an application to the nanoemitter, we investigated the nanofabrication of diamond-like carbon (DLC)-dot arrays by room-temperature curing imprint-liftoff (RTCIL) method using aluminum mask. The DLC film which has excellent properties similar to diamond properties was used as the patterning material. A polished glass like carbon (GC) was used as a mold material. The polysiloxane in the state of sticky liquid at room temperature and stable in air exhibits a negative-exposure characteristics. Therefore, the polysiloxane was used as electron beam (EB) resist and oxide mask material in EB lithography, and also used as RTC-imprint resist material. An aluminum was used as oxide metal mask material of liftoff. We have fabricated the GC mold of dot arrays with 5 µm-square and 500 nm-height. We carried out the RTCIL process using the GC mold under the following optimum imprint conditions: 0.5 MPa-imprinting pressure and 5 min- holding time. Aluminum film on the imprinted polysiloxane was prepared by vacuum evaporation method and its thickness is 20 nm. Finally, the polysiloxane patterns were removed with acetone and aluminum mask patterns were fabricated. We found that the maximum etching selectivity of aluminum film against DLC film was as high as 35, which was obtained under an ion energy of 400 eV. Then we processed the patterned aluminum on DLC film with an ECR oxygen ion shower. We fabricated DLC-dot arrays with 5 µm-square and 400 nm-height with an aspect ratio of 0.08.

We have investigated the counter intuitive phenomenon of inserting a metal oxide layer to improve hole injection or extraction in organic semiconductor devices using ultraviolet photoemission, x-ray photoemission, and inverse photoemission spectroscopy (UPS, XPS and IPES). We observed that metal oxides, such as MoO3, substantially increase the work function when deposited on indium-tin-oxide (ITO). The increase lifts up the highest occupied molecular orbital (HOMO) of the hole transport layer, therefore reduces the energy barrier between the HOMO and the Fermi level of the anode. The uplift creates an interface band bending region that results in a drift electric field that encourages the collection of holes at the anode. The optimum thickness for the oxide layer is estimated to be 2 nm. We have also investigated the effects of ambient or O2 exposure of MoO3. We observed that while most of the electronic energy levels of the oxide remained largely intact, the work function reduction was significant. This opens a way for optimal energy level alignment by modifying the work function through exposure. Furthermore, we observed that the work function reduction by exposure could be reversed by proper annealing of the sample in vacuum. The investigations therefore point to manipulate the interface electronic structure and charge injection/extraction by thin metal oxide films.

The paper presents a comparative study of the photoluminescence (PL) and Raman scattering spectra of core-shell CdSe/ZnS quantum dots (QDs) in nonconjugated states and after the conjugation to the anti-human papilloma virus (HPV), HPV 16-E7, antibodies. All optical measurements are performed on the dried droplets of the original solution of nonconjugated and bioconjugated QDs located on the Si substrate. CdSe/ZnS QDs with emission at 655 nm have been used. PL spectra of nonconjugated QDs are characterized by one Gaussian shape PL band related to the exciton emission in the CdSe core. PL spectra of bioconjugated QDs have changed essentially: the core PL band shifts into the high energy spectral range (“blue” sift) and becomes asymmetric. A set of physical reasons has been proposed for the “blue” shift explanation of the core PL band in bioconjugated QDs. The variation of PL spectra versus excitation light intensities has been studied to analyses the exciton emission via excited states in QDs. Finally the PL spectrum transformation for the core emission in bioconjugated QDs has been attributed to the electronic quantum confined effects stimulated by the electric charges of bioconjugated antibodies.

Hydrogels consisting of the conducting polymer PEDOT:PSS and the biopolymer gellan gum (GG) were characterized using electrical, mechanical and rheological methods. Compression testing and rheological analysis showed that the gels weakened with increasing PEDOT:PSS content. In contrast, the increasing PEDOT:PSS content resulted in an increasing electrical conductivity.

Thin-films of magnetic nanoparticles (MNPs) with high coercivities are deposited onto surfaces for use in data storage applications. This usually requires specialist clean-room facilities, sputtering equipment and high temperatures to achieve the correct crystallographic phases. One possible cheaper and more environmentally friendly alternative could be to use biomolecules. Many biomineralization and biotemplating molecules have been identified that are able to template a wide range of technologically relevant materials using mild, aqueous chemistry under physiological reaction conditions. Here, we have designed a dual affinity peptide (DAP) sequence to template MNPs onto a surface. One end of the DAP has a high binding affinity for SiO2 and the other for MNPs of the L10 phase of CoPt, a high coercivity magnetic material. Images of the biomineralized substrates show that nanoparticles of CoPt are localized onto the areas that were functionalized with the biotemplating DAP. Magnetic force microscopy (MFM) plots of the biotemplated nanoparticles show that there is magnetic contrast on the patterned surface.

Silicon carbide has long been a promising material for semiconductor applications in high-temperature environments. Although silicon carbide radiation detectors were demonstrated more than a half century ago, the unavailability of high-quality materials and device manufacturing techniques hindered further development until about twenty years ago. In the late twentieth century, the development of advanced SiC crystal growth and epitaxial chemical vapor deposition methods spurred rapid development of silicon carbide charged particle, X-ray and neutron detectors. The history and status of silicon carbide radiation detectors as well as the influence of materials and device packaging limitations on future detector development will be discussed. Specific silicon carbide materials development needs will be identified.

Thin-film silicon solar cells have been attracted a lot of intention as low-cost solar cells. One of the most important technologies for improving their performances is light trapping. We have demonstrated the high potential of double-textured zinc oxide (ZnO) thin films used as front transparent conductive oxide (TCO) films due to further enhancement of their light-trapping effects. Although the laser scribing method has already been well established for low-cost thin-film silicon solar cell module manufacturing, laser scribing technique on double-textured ZnO is new and still a challenging issue. In this study, we firstly demonstrated the availability of laser scribing for amorphous silicon (a-Si) solar cells fabricated on double-textured ZnO substrates. It is general to utilize lasers with wavelength of 1.06 μm and 532 nm for scribing of TCO and silicon layer, respectively. Here we attempted to scribe both of TCO and silicon layers using a 532 nm wavelength laser (green laser) for process simplifying.

In this work, we numerically investigated the achievable fidelities when controlling an effective three-qubit system consisting of a NV- color center in diamond with a nearby strongly coupled 13C nuclear spin by means of microwave- and radio-frequency pulses in the experimentally attractive low magnetic field regime. We find that gates with straightforward square driving pulses do not achieve the fidelity currently required for the fault-tolerant quantum computing models.

We report on mid-infrared (600 – 4000 cm-1), refection-type optical-Hall effect measurements on epitaxial graphene grown on C-face silicon carbide and present Landau-level transition features detected at 1.5 K as a function of magnetic field up to 8 Tesla. The Landau-level transitions are detected in reflection configuration at oblique incidence for wavenumbers below, across and above the silicon carbide reststrahlen range. Small Landau-level transition features are enhanced across the silicon carbide reststrahlen range due to surface-guided wave coupling with the electronic Landau-level transitions in the graphene layer. We analyze the spectral and magnetic-field dependencies of the coupled resonances, and compare our findings with previously reported Landau-level transitions measured in transmission configuration [4,5,6]. Additional features resemble transitions previously assigned to bilayer inclusion [21], as well as graphite [15]. We discuss a model description to account for the electromagnetic polarizability of the graphene layers, and which is sufficient for quantitative model calculation of the optical-Hall effect data.

Power consumption and dissipation during electrical operation lead to a temperature rise in the package. Elevated temperature in the package structure induces thermo-mechanical stresses which may increase reliability risks. Robust and reliable package design for power systems requires comprehensive analysis of system electrical, thermal, and mechanical behavior. This paper presents a self-consistent approach for package reliability analysis with coupled electro-thermal and thermo-mechanical modeling using TCAD tools.

Accumulated body [1] approach to mitigate the effects of line edge roughness on bulk silicon finFETs and tri-gate FETs is analyzed through 3D TCAD simulations. A side-gate surrounding the body portion of the FET is used to accumulate the body with majority carriers. This approach is predicted to reduce device-to-device variability due to line edge roughness by stronger accumulation of the body in the wider sections of the channel and confinement of the channel away from the edges.

This research presents a new fabrication method for tailoring polymer/carbon nanotubes (CNTs) nanostructures with controlled architecture and composition. The CNTs are finely dispersed in a polymeric latex i.e. polyacrylate, via ultrasonication, followed by a microfiltration process. The later step allows preserving the homogeneous dispersion structure in the resulting solid nanocomposite. The combination of microfiltration and proper choice of the polymer latex allows for the design of complex nanostructures with tunable properties e.g., porosity, mechanical properties. An important attribute of this methodology is the ability to tailor any desired composition of polymer-CNTs systems, i.e., nanotubes content can practically vary anywhere between 0 to 100 wt%. Thus, for the first time a given polymer/CNTs system is studied over the entire CNTs composition, resembling immiscible binary polymer blends. The polymer in these systems exhibits a structural transition from a continuous matrix (nanocomposite) to segregated domains dispersed within a porous CNTs network. An analogy of this structural transition to phase inversion phenomena in immiscible polymer blends is suggested.

With general lighting applications being responsible for over 20% of the energy consumption in the United States, advances in solid-state lighting have the potential for considerable energy and cost savings. The United States Department of Energy predicts that the increased use of solid state lighting will result in a 46% lighting consumption energy savings by the year 2030. Smart lighting systems have the potential for reducing energy costs while also providing a means for short distance data transmission via free space optics. The group III-nitride (III-N) family of materials, including aluminum nitride (AlN), gallium nitride (GaN), indium nitride (InN), their binary and ternary alloys, are uniquely situated to provide light emitting diodes (LEDs) across the full visible spectrum, photodetectors (PDs) and high power, high speed transistors. In this work, aluminum gallium nitride (AlGaN) / GaN high electron mobility transistors (HEMTs) and indium gallium nitride (InGaN) photodiodes (PDs) are fabricated and characterized. HEMTs and LEDs (or PDs) are grown on the same substrate for the purpose of creating electronic and optoelectronic integrated circuits.

In this study, synthesis and characterization of rutile-Titanium dioxide (TiO2) thin films using pulsed DC Magnetron Sputtering at room temperature, along with the fabrication and characterization of MIM capacitors have been discussed. XPS and RBS data show that the films are stoichiometric and have compositional uniformity. The influence of electrode materials on electrical characteristics of the fabricated MIM capacitors has been studied. The Al/TiO2/Al based capacitors show low capacitance density (9 fF/μm2) with low dielectric constant (K=25) and high EOT (3.67 nm) due to low dielectric constant TiO2 phase formation on Al/Si substrate. On the other hand, Ru/TiO2/Ru based capacitors show high capacitance density (49 fF/μm2) with high dielectric constant (K=130) and low EOT (0.7nm) values at high frequency (100 KHz) due to high dielectric constant phase (rutile) formation of TiO2, on Ru/Si substrate. Raman spectra confirm that the films deposited on Ru/Si substrate show the rutile phase.

In this study, we fabricated blue OLEDs with quantum well structure (QWS) using four different blue emissive materials such as DPVBi, ADN and DPASN, and BAlq as QWS material. Conventional QWS blue OLEDs used to be composed of emissive layer and charge blocking layer with lower HOMO-LUMO energy level, but we designed triple emitting layer for more significant hole-electron recombination in EML and a wider region of exciton generation as forming QWS spontaneously. The structure of triple emitting layered blue OLED is ITO / NPB(700 Å) / X(100 Å) / BAlq(100 Å) /X (100 Å) / Bphen(300 Å) / Liq(20 Å) / Al(1200 Å) (X= DPVBi, ADN, DPASN). HOMO-LUMO energy levels of DPVBi, ADN, DPASN and BAlq were 2.8-5.9, 2.6-5.6, 2.3-5.2 and 2.9-5.9 eV, respectively. The maximum luminous efficiency was 5.32 cd/A at 3.5 V in a blue OLED with DPASN / BAlq / DPASN QWS.

Hydrothermal synthesis of ThO2, UxTh1-xO2, and UOx at temperatures between 670°C and 700°C has been demonstrated. Synthesis at these temperatures is 50-80°C below prior growth studies and represents a new lower bound of successful growth. ThO2 single crystals of dimensions 6.49mm x 4.89mm x 3.89 mm and weighing 0.633g have been synthesized at average growth rates near 0.125mm/week. Single crystal UxTh1-xO2 crystals with mole fractions up to x≈0.30 have also been grown. The largest alloyed crystal with mole fraction x≈0.23 has dimensions of 2.97mm x 3.23mm x ∼3mm and recorded average growth rates near 0.2mm/week. Four structures were solved from X-ray diffraction data and their crystallographic data reported here. Rocking curve analysis determined a dislocation density of 1.2×109 cm-2.

The effect of thermal annealing on the optical properties of Al2O3 films with different Si content was investigated by the photoluminescence method. Si-rich Al2O3 films were prepared by RF magnetron co-sputtering of the silicon and alumina targets on long quarts glass substrates. Photoluminescence (PL) spectra of freshly prepared Si-rich Al2O3 films are characterized by three PL bands with the peak positions at 2.97-3.00, 2.25-2.29 and 1.50 eV. The thermal annealing of the films at 1150 °C during 30 min stimulates the formation of Si nanocrystals (NCs) in the film area with Si content exceeded 60%. After the thermal annealing the PL intensity of all mentioned PL bands decreases and the new PL band appears with the peak position at 1.67 eV. The new PL band is attributed to the photo currier recombination inside of Si NCs. The size of NCs estimated from the PL peak position 1.67 eV of Si NC emission is about ∼-4.5-5.0 nm.

The temperature dependences of PL spectra of Si-rich Al2O3 films have been studied in the range of 10-300K with the aim to reveal the mechanism of recombination transitions for mentioned above PL bands 2.97-3.00, 2.25-2.29 and 1.50 eV in freshly prepared films. The thermal activation of PL intensity and permanent PL peak positions in the temperature range 10-300K permit to assign these PL bands to defect related emission in Al2O3 matrix.