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Organic-inorganic multilayer structures of the silicon/poly (diphylenepthalide)/Cu type were prepared and their electrical properties were studied. The obtained results were treated within different models of charge transport and it was concluded that the dominant charge injection mechanism at higher temperatures is the thermionic emission.

Organic-inorganic multilayer structures of the silicon/poly (diphylenepthalide)/Cu type were prepared and their electrical properties were studied. The obtained results were treated within different models of charge transport and it was concluded that the dominant charge injection mechanism at higher temperatures is the thermionic emission.

The nanoporous Ti[O.sub.2] network sensitized by ZnS nanospheres is produced and described as an idealized scheme to facilitate interfacial charge transfer effects. The findings suggest that when a large band gap material is restricted in a confined geometry of lower energy band gap then the surface states are mainly responsible in the charge transport phenomena.

The charge trapping phenomenon in fluorene-based conjugated polymer poly[9,9-bis(2-ethylexyl)fluorene-2,7-diyl] (PF2/6) and poly[9,9-bis(2-ethylhexyl)fluorene-2,7-diyl] end capped with hole-transporting moieties N, N-bis(4-methylphenyl)-N-phenylamine (PFe/6am 10) is investigated. The thermally stimulated current spectra displays a striking difference with the polarity of load voltage for conjugated polymers, implying an important role of electrodes on the charge-carrier photogeneration in these polymers.

A detailed study of charge transport in electrophosphorescent organic semiconductors is reported. The study shows that by increasing the generation of the dendrimer, the mobility is lowered and the level of disorder in the film is not increased, as reflected in identical levels of tail broadening for the first- and second-generation material.

The room temperature electrical characteristics of biopolymer gold nanoparticle complexes show threshold behavior, periodic conductance features, and current-voltage scaling that together indicate the nonlinear transport is associated with single electron charging. The current voltage scaling behavior is found to be time independent, while the position of the conductance features shifted randomly over periods of many hours.

The effects of charge transfer between atoms on an amorphous SiO(sub 2), surface were studied by comparing a model with fixed charge (FQ) and a model that takes into consideration charge transfer by the charge equilibrium (QEq) method. The results suggest that consideration of the charge transfer is essential to reproduce the defect structure of the silica glass surface.

A two-dimensional sheet charge and mobility in GaN/AlGaN heterostructure field effect transistors is investigated. Experimental results on samples grown by metal organic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE) are reported, whereas, theoretical studies are performed to examine the spontaneous polarization and piezoelectric effect to control the sheet charge density.

Ar(+) plus Ar and Ar(++) plus Ar differential and integral cross sections, used for modeling ion scattering, include differential scattering data and symmetric charge transfer collisions. These techniques enhance the precision of Monte Carlo computations that represent energy, temporal and angular distributions of the cross section ions. The cross sections required for modeling energy dissipation in gas are also analyzed.

An increase in the nonlinearity factor, alpha, leads to strange, chaotic behavior of the charge Q(t) and decreased mean charge buildup in a closed quantum-mechanical system. The electric field marginally affects the chaotic properties of the charge buildup at resonance by an external negative field action on the double-barrier heterostructure. Average charge buildup in the structures increases with nonresonant electric fields.

A sequence of alternating voltage pulses is applied to a ZnS:Mn metal-insulator-semiconductor-insulator-metal (MISIM) to analyze the current pulse shape evolution. Hole traps are involved in the charge transfer process. Competition between the carrier multiplication and their recombination of hole traps determine the current pulse evolution. Basic processes in MISIM structure are explained theoretically. Time evolution of the current pulses are quantitatively explained.

Simultaneous measurement of light-induced excess microwave reflectivity and anodic photocurrent allows the separation of surface recombination velocity and charge transfer velocity. Dynamic interface properties of n-type Si(111) in 0.2 M NHF solution revealed that such separation was possible.

AlPcCl films, prepared by vacuum deposition on substrates of KCl(001) surface and glass, exhibit structure-reliant electrical and photoconductive properties. Photoconductive properties vary due to changing oxygen doping and carrier recombination. Charge transfer from excited AlPcCl to oxygen causes photogeneration of free carriers. Oxygen doping and carrier recombination are influenced by the morphology and molecular orientation.

Measurement of the surface potential of the polyimide (PI) Langmuir-Blodgett (LB) films yields the spatial distribution of charges in ultrathin PI LB films. The surface potentials are measured as a function of various deposited layers. PI LB films are 0.4 nanometers thick and are deposited on metals. The metal electrodes exhibit a depth penetration of excess charges to about 3 nanometers. The excess charge transfer occurred till a thermodynamic equilibrium is achieved.

Resistivity, carrier mobility and density of charge carriers of epsilon1-Cu3Ge thin films indicate that they are metals with an electric resistivity of 6 micro-ohmcentimeters at room temperature. The Block-Gruneisen relation and a Debye temperature of 240 Kelvin influence the temperature dependence of the resistivity. The temperature and film thickness have no influence on the hole density.

Hot carrier stressing with maximum substrate current biasing condition yields interface traps in metal-oxide-semiconductor field effect transistors. The device, when placed at room temperature for 24 hours, does not anneal the interface traps, which is contrasting to the properties of the trapped oxide charged devices. The hot carrier traps are completely annealed by reverse bias coupled to high positive drain voltage.

Atheoretical model that included surface photovoltage effect (SPV) signals and ambipolar diffusion lengths in undoped semi-insulating GaAs was developed to study SPV. Difference of carrier mobilities caused large SPV signals. Ambipolar diffusion lengths were found to be 1.4 micrometers for GaAs. The surface electrostatic field, as depicted by the model, was extremely small.

Capacitance measurements which were a function of bias in GaAs double barrier structures at low and high pressure regimes revealed evidence of electron redistribution. The Fermi level, due to the variation of capacitance with bias, attached to the lowest X level in each well at low bias. At larger bias, the collector well was depleted.

Fast retrapping defined the transport mechanism of detrapped charges in thermally wet grown SiO2 electrets and was significant to negative charge carrier release. The thermally wet grown SiO2 was initially charged by either the corona method or the electron-beam irradiation before it aged at various temperatures. Retrapping occurred in energetically deeper trap levels which were found in the oxide bulk.

A Monte Carlo simulation model using Monte Carlo algorithms for hot-electron transport and charge trapping describes charge-trapping and detrapping as electron-irradiated alpha-quarte, and relates the trapped charge distribution to sample size and temperature variations. Alpha-quarte size effect values agree well with experimental scanning electron microscope readings. The simulation model predicts size effect variation with temperature.

Schrodinger equation facilitates the examination of the characteristics of electrons in quantum field effect directional coupler. Transverse confinement affects the transfer length, which is revealed by the measurement of the transfer length for the two theoretical models of the transverse confinement. Transfer of efficiency decreases due to correspondence between various modes, and total transfer is seen exclusively in a single mode.

Strain-induced electric fields affect the distribution structure. The piezoelectric characteristics of a GaN-AlN-GaN semiconductor-insulator-semiconductor structure with the growth axis along a crystallographic direction is examined. Flat band voltage can be displaced by the strain-induced electric fields forming a depletion area on one side and an accumulation area on the other side of the AlN insulator.

The charge transfer collision cross section of positively charged He ions and in a helium plasma is determined by using the plasma immersion ion implantation technique. The impurity profile in silicon substrate after PIII is used in the derivation of the ion energy. A new cross section for the He ions is obtained, which is used in the PDP1 stimulation.

The nonuniform polarization charging effects on the ion drag force are investigated in drifting dusty plasmas. The results show that the nonuniform charging effects enhance the momentum transfer cross section as well as the ion drag force.

A numerical magnetostatic three-dimensional (3D) shield model for use within the generic micromagnetic models is described. Each shield object in the model is influenced by an induced magnetic charge distribution on its boundary surfaces.

Analysis of the temperature dependence of cathodoluminescence intensity in a GaAs-AlGaAs single quantum well fabricated by molecular beam epitaxy reveals a thermally activated carrier transfer from wider to narrower quantum well regions upon temperature increase. This carrier transfer suggests an exciton localization within the wider quantum well regions at low temperatures. The exciton localization affects the contrast in cathodoluminescence images of the quantum well.

Several studies are conducted to explain the different quenching mechanisms exhibited by the optical centers present in the [Eu.sup.3+]-doped nanophosphors under charge transfer excitation. The various mechanisms that can be adopted for enhancing the luminescence efficiency of these nanophosphors are also discussed.

The article explains the formation and properties of an electrically bistable device, prepared by the spin-coating method by employing different silver nanoparticle-poly(N-vinylcarbazole) composites. The induced charge transfer and negative differential resistance behavior are shown to be the main determinants of the electrical bistability exhibited by the device.

A versatile, robust and efficient means are provided for simulating organic semiconductor devices, which have allowed for the direct solution of the steady-state drift-diffusion problem. The studies have shown that the numerical methods have performed well in combination with advanced physical transport model such as energetic Gaussian disorder, density-dependent and field-dependent mobilities, the generalized Einstein diffusion, traps, and its consistent charge injection model.

The segmented contact method is employed to explain determine the different factors that determine the threshold current density dependence of the Stranski-Krastanov quantum dot devices. The dependence of the lateral ambipolar diffusion length on the carrier injection-level of these devices is also analyzed.

The impact of the substrate-induced strain on the different transport properties of the AlGaN/GaN heterostructures grown on the Si substrates is analyzed. A reduction in the Si thickness is shown to lead to an increase in the density of the heterostructures.

Several studies are conducted to analyze the various electrical properties of the Si nanocrystals under dark and solar light exposure. The photocarrier generation ratio of the nanocrystals is shown to average out over the solar spectrum region.

The thickness dependence of cadmium telluride/cadmium selenide (CdTe/CdSe) heterojunctions is analyzed in order to maximize the performance of solar cells. The studies have shown that the power efficiency is strongly dependent on the thickness of the nanoparticle layer, which is contrast to thin film CdTe solar cells, and has also displayed that the device is limited by charge transport.

The transmission electron microscopy images of in situ prepared multiwall carbon nanotubes (MWNTs) and polyaniline (PANI) composites have shown that nanotubes are well dispersed in aqueous medium and the nanofibers of PANI has facilitated intertube transport. The onset frequency for the increase in conductivity is dependent on the MWNT weight percent and the negative magnetoresistance is attributed to the forward interference scattering mechanism in variable range hopping (VRH) transport.

ZnO thin films and [([Bu.sub.4]N).sub.2](Ru)[(dcbpyH).sub.2][(NCS).sub.2] (N719) sensitized ZnO thin films are grown on fluorine-doped tin oxide (FTO) conducting glass substrates by using laser molecular beam epitaxy and the transition process of photogenerated charges and the interaction between ZnO and N179. The interaction has enhanced the photogenerated charge separation and the photovoltaic response of the ZnO film, but has weakened its radiative recombination, implying strong energy and charge transfer occurring between N179 and ZnO.

The full potential augmented plane wave plus local orbital method using the local density approximation within the framework of density functional theory is used for examining structural, electronic and thermodynamic properties of [Sn.sub.x][Ge.sub.1-x] alloys for small Sn compositions. The studies have shown that the instability of SnGe alloys is dominated by a strong charge transfer between Sn and Ge, which has led to a positive chemical energy, where the instability is amplified by positive strain energy.

The reactive dc magnetron sputtering and the self-ordered Ge nanocrystal formation during subsequent annealing are used to achieve the deposition of (Ge[O.sub.x]-Si[O.sub.2]) superlattices. The Ge nanocrystal layers which could be separated by very thin Si[O.sub.2] films offer interesting possibilities for charge transport via direct tunneling.

A Raman scattering study of epitaxial graphene on different doped 6H-SiC (0001) substrates was conducted to examine the substrate induced charge-transfer doping to the epitaxial graphene. The obtained results might have significant implications for future epitaxial-graphene-based micro/nanoelectronic devices.

A homogenization theory based on a multiple scale perturbation of the charge-transport equation is used to derive a mathematical framework for modeling the cumulative effect of Te inclusions in radiation detectors based on semi-insulating cadmium zinc telluride (CdZnTe). The derived framework which naturally incorporates a wide range of physical models could be applied to a simplified version of the geometric model.

Top-gate polymer field-effect transistors which are generated based on charge accumulation in bilayers of two semiconducting polymers are reported. The results indicated that in order to block the charge transfer across the heterojunction, at least 1.eV offset is required between the ionization potential