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In this work, we present an n-type Passivated Emitter and Rear Totally diffused Rear Junction (n-PERT-RJ) solar cell structure with a dot-shaped Laser Contact Opening (LCO) pattern on the rear side. The fully screen printed devices are investigated for rear side Al paste metallization with various Si-additive content. A hypothesis of the screen printed point contact formation and the role of the Si-additives played in the alloying process are proposed based on the analysis of microstructure and electrical properties of the solar cells. Adapted process conditions led to an n-PERT-RJ solar cell with 21.78% efficiency and 686mV open-circuit voltage. The process fits to simple industrial implementation and has the potential to exceed the 22% efficiency level in mass production. [ABSTRACT FROM AUTHOR]

The deformation between interface and adhesion mechanism of multi-layer flexible electronics composite were discussed. First, ITO (Indium tin oxide), Al (Aluminum) and ZnO (Zinc oxide) were directly deposited on a PET (Polyethylene terephthalate) substrate by RF (Radiofrequency) magnetron sputtering in room temperature to form the flexible multi-layer structures (ZnO/ITO/PET and ZnO/Al/PET) for piezoelectric transducers. ZnO thin film reveals a high (002) c-axis preferred orientation at 2θ=34.45° with an excellent piezoelectric property. To analyze adhesion following a periodic mechanical stress by vibrating flexible composite plates, nano-scratching test (Nanoindenter XP system) was used for scratch process to learn the relationship between normal force and penetration depth. The results show that the plastic deformation can be observed from SEM and OM observation between Al film and PET substrate. This behavior means that the deposited ZnO film has excellent adhesion with Al/PET conductive substrate compared with ITO/PET. Through nano-indentation test, ZnO film deposited on Al/PET substrate decreased the elastic modulus and hardness compared with ITO/PET substrate. [ABSTRACT FROM PUBLISHER]

Rocket propellant has been identified as a component that played an important role in the development of rockets. The ejected material in rocket propulsion is due to material called propellant. Without propellant, a rocket cannot be launched. Due to this reason, many have started to conduct research on new chemical compound of propellant with new technique if needed. The objectives of this study are to study the thermo-chemistry aspect of the composition and to determine the burning characteristics parameters. For this reason, this dissertation presented a detail preparation of developing a solid propellant using Ammonium Perchlorate (AP) as an oxidizer, Aluminum (Al) as fuel and Hydroxyl Terminated Polybutadiene (HTPB) as the binder. To determine the propellant performance such as burning rate, testing was conducted. From testing result the propellant composition oxidizer-fuel (76/11) at pressure 110 Psi gave the maximum burning rate. From test results the empirical constant, ‘a’ and pressure exponent ‘n’ were calculated for each different propellant compositions. [ABSTRACT FROM AUTHOR]

The warm, dense matter (WDM) regime requires a sophisticated treatment, since neither ideal gas laws or fully ionized plasma models apply. Mixtures represent the predominant form of matter throughout the universe and the ability to predict the properties of a mixture, through direct simulation or from convolution of the properties of the constituents is both a challenging prospect and an important goal. Through quantum molecular dynamics, we accurately simulate WDM and compute equations of state, transport, and optical properties of such materials, including mixtures, in a self-consistent manner from a single simulation. With the ability to directly compute the mixture properties, we are able to validate mixing rules for combining the optical and dynamical properties of Li and H separately to predict the properties of lithium hydride (LiH). We have examined two such mixing rules and extend them to morphologies beyond a simple liquid alloy. We have also studied a mixture of polyethylene and aluminum at T = 1 eV. [ABSTRACT FROM AUTHOR]

An investigation into measured differences in surface contaminant levels when evaluating several ion implant tools and/or tool types. For a given species and energy, beam current appears to have a strong effect on final contaminant levels. Ideally one evaluates process integrity at machine set-up conditions that approximate or exceed the worst case conditions required for regular, volume wafer production. Some contaminants may exhibit a ‘threshold’ effect where they are easily observed with sufficient beam current, but not present at all for lower beam currents. Knowing the characteristics of the measurement process is essential in obtaining reliable results with a clear interpretation and better facilitates cross-site or cross-platform comparisons. [ABSTRACT FROM AUTHOR]

Mechanical and microstructural properties of high density PTFE/Al/W composites consisting of PTFE matrix, aluminum and tungsten particles were investigated. Three types of samples having different porosities and particle sizes of W with an identical weight ratio between PTFE, Al and W were fabricated by Cold Isostatic Pressing. The quasi-static and Hopkinson Bar compression tests were employed to investigate the mechanical properties of these materials. The results demonstrated that the porous PTFE/Al/W composite samples containing fine W particles have higher quasi-static and dynamic fracture stresses than higher density PTFE/Al/W samples containing coarse W particles. ESEM micrographs revealed that deformation occurred mainly in the PTFE matrix while metal particles remain undeformed. We observed nano-fibers of PTFE caused by high strain rate deformation. [ABSTRACT FROM AUTHOR]

We present 3D-nonequilibrium molecular dynamics results for the velocity dependence of the frictional force at smooth sliding interfaces for Ta and Al single crystals. For Ta/Al we consider Al(100)/Ta(100) and Al(111)/Ta(110) interfaces sliding along [001] and [110]fcc /[001]bcc respectively. These are compared with Al(111)/Al(100) interfaces at the same loads, corresponding to a pressure of 15 GPa. Both interfacial pairs show similar behavior in the velocity dependence of the frictional force: a low velocity regime with an increasing frictional force followed by a strain induced transformation regime at velocities above approximately 1/10 the transverse sound speed, followed by a fluidized interface at high velocities. For both interfacial pairs, the high velocity dependence of the frictional force exhibits power law behavior, Ft ∝ v-β with β=3/4. We discuss the structural changes that influence dissipation in each of these regimes. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Hopkinson bar based thick walled cylinder (TWC) method was developed to collapse hollow cylinders with small mass about 0.5 gram made from the mixtures of PTFE and Al particles of different sizes (2 and 95 μm). Different media (water, suspension of alumina particles in water, and glycerol) in different geometrical configurations were investigated to ensure the collapse of hollow cylinders with a single pressure pulse under pressure/time conditions achievable in Hopkinson bar tests. Raman spectroscopy of the samples of PTFE and 2 μm aluminum particles mixtures demonstrated the evidence of the decomposition or reaction of PTFE inside the shear localization area or cracks. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

In-situ local measurement of thermal and sub-threshold, electromigration-induced strains in a 0.3 micron wide Al interconnect was performed using convergent beam electron diffraction (CBED) in a TEM. The CBED method offers the unique ability to probe local strain variations, in this experiment with 0.1 micron resolution. Spatially averaged strain measurements resulting from both thermal treatment and electromigration quantitatively agree with models and data from previous studies. Interesting observations emerged when comparing the local strain distribution within and between grains. Thermal cycling resulted in grain size dependent plastic behavior and electromigration testing led to strain redistribution within individual grains. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper applies rational choice theory to help explain why two transnational television news networks, CNN and Al-Jazeera, made sharply contrasting decisions about airing a videotaped interview with Osama bin Laden in the months following the September 11 attacks. Both organizations sought to justify their decisions in terms of professional norms, particularly in expressing their autonomy of news judgment. However, as geopolitical actors, the networks faced far different structural considerations. Al-Jazeera, which still depended on the sponsorship of the emir of Qatar, had to weigh the consequences of its decision on its reputation as an emerging independent network. The networks' varied strategies reveal the gamesmanship inherent in global mass communication and suggest as well that audiences are inheriting the potential for more complex understandings. [ABSTRACT FROM AUTHOR]

Investigations have been carried out on the deposition of compact uniform and continuous lead layers on the surfaces on aluminum and copper nets. No defects in lead layer were studied by scanning tunnel microscopy. The lead film electrodes on the copper and aluminum nets feature good electrochemical and corrosion characteristics [ABSTRACT FROM PUBLISHER]

An EPROM cell structure is described that uses folded word lines with double Al layers. Cell characteristics are optimized to obtain high-speed access. The data retention reliability and erasability are studied, focused on a 2Al metallization process. The feasibility of the technology has been confirmed by a 1-Mb CMOS EPROM device which shows 16 ns access time and extremely high data retention reliability. Process and device parameters are summarized. An 0.8-μm N-well CMOS, 1 poly Si+1 MoSi polycide double metal technology is used. To fabricate 5-V and 12.5-V high-voltage NMOS and PMOS transistors simultaneously, masked lightly-doped-drain structures are used [ABSTRACT FROM PUBLISHER]

Summary form only given. The layout of the IGNITEX facility was modeled, and the activation responses of the various candidate materials were determined. The ONEDANT code was used to simulate the neutron transport, and the REAC2 code was employed to evaluate neutron activation. Neutron cross sections for the transport calculation were derived from the VITAMIN-E library. Steel, aluminum, copper, titanium, and Inconel were analyzed as vacuum vessel materials. Both GlidCop and BeCu copper alloys were studied as magnet materials. Steel, aluminum, and fiberglass were considered as cryostat materials. Different materials for cryostat covers were investigated. It is concluded that, in selecting component materials, it is important to account for activation levels and for additional shielding requirements for hands-on maintenance [ABSTRACT FROM PUBLISHER]

Summary form only given. Extensive studies of spectroscopic measurements of IADI (ion-acoustic decay instability) in laser-produced plasma have been made. The experiments were performed using the GDL (gas dynamic laser) laser facility at LLE and the Janus (Phoenix) laser and NOVA laser facilities at LLNL. The laser is incident normally onto a planar target (CH, Al, Cu, Mo and Au of 50-μm thickness) with a 1-ns FWHM Gaussian pulse and a maximum energy of 200 J. The IADI was studied by monitoring the Stokes sideband of the backscattered (0 and 45°) spectrum near the second harmonic of the laser light. Two spectrometers were used to measure the angular dependence of the time integrated 2ω signal. Extensive studies of IADI have been made: (1) measurements of the threshold vs. laser spot size, (2) laser wavelength scaling (1-μm and 0.5-μm laser irradiations), (3) plasma flow effect, measurements of the angular dependence of 2ω signal, (4) measurements of IADI in high-Z target, ionic charge state Z, and IADI vs. target material, and (5) the measurements of IADI in the high-laser-intensity regime. The thresholds of the IADI are quite low, even with the high-Z target, so that IADI is potentially important in laser-produced plasma [ABSTRACT FROM PUBLISHER]

In this work, molecular dynamic (MD) simulations are performed for Al based on the embedded atom method (EAM). P-T diagrams are determined, the bulk moduli, the radial distribution functions, are also calculated. The computed thermodynamic parameters are found, generally, to be in good agreement with the available experimental data. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Summary form only given. A large number of 1-D magnetohydrodynamic (MHD) calculations of Al and Ni array implosions have been carried out for a set of idealized current conditions. The calculations indicate the pulse power machine requirements that are needed in these idealized implosions to produce large X-ray yields efficiently. These calculations have important implications for pulse power machine, diode, and load design [ABSTRACT FROM PUBLISHER]

Summary form only given. An extensive aluminum wire array experiment has been performed. Wire arrays of 6-25-mm diameter have been imploded on the 6-TW Double-EAGLE generator. With the masses adjusted so that the implosion time was between 85 and 95 ns, an optimum aluminum K-shell yield of 30 kJ was obtained with an array diameter of 12.5 mm. Analyses were performed which indicate that the kinetic energy per ion for this implosion was 18 keV, which is greater than the 12 keV required to ionize to heliumlike aluminum if radiation losses are neglected. Under this condition, the total implosion kinetic energy is comparable to the radiated K-shell energy but very much less than the total radiated yield. Furthermore, comparing the measured K-shell yield to those predicted by a one-dimensional radiation-magnetohydrodynamic code, which only assumes motional kinetic energy as the energy source, indicates that kinetic energy alone cannot account for the radiation. To explain this, other heating mechanisms such as ohmic heating, 2-D effects, or plasma bouncing can be invoked. Data from the time- and space-resolved X-ray and spectroscopic diagnostics were obtained in an effort to extract pointers to the other heating mechanisms. In particular, time-resolved crystal spectra were used to study the variation of plasma electron temperature and density in time when analyzed with the appropriate CRE models [ABSTRACT FROM PUBLISHER]

Summary form only given. All experimental study of the radiation emission from aluminum and magnesium X-pinch experiments was conducted. The single cross X-pinch, driven by the 0.5 TW, 40-ns-pulse-width Lion accelerator, consists of 2-8 fine wires stretched between the output electrodes of Lion so as to touch at a single point. The number and size of Al and Mg wires were varied in order to optimize the K-shell line radiation. K-shell line radiation as well as harder radiation at 4-4.5 keV were observed to be emitted from a submillimeter region at the crossing point of the wires for both the aluminum and the magnesium X-pinch. The presence of the 4-4.5-keV component of the radiation from all as yet unidentified mechanism reduced the estimate of the optimized energy yield in the Al K-shell (1.6-1.7 keV) in an earlier experimental run. In the present run, a total yield of 20±10 J in K-shell radiation is estimated for loads consisting of two 50-μm Al wires with peak currents up to of 450 kA. This current is reduced by 20% from that of the previous run. Optimization of the K-shell emission from a magnesium x-pinch results ill a K-shell (~1.4 keV) radiation yield of 40±20 J and 1-5 J of harder radiation with a 450-kA peak current [ABSTRACT FROM PUBLISHER]