The recent development of bright X-ray sources, reliable X-ray focusing optics, large X-ray detectors and X-ray data modelling and processing, have improved X-ray techniques to the point where many are being introduced in MOS transistor manufacturing lines as new metrology methods. The fundamental X-ray physical properties, such as their small wavelength and their weak interaction with solid-state matter satisfy basic in-line metrology requirements: non-destructiveness, speed, accuracy, reliability and long-term stability. The capability of X-ray based metrology methods to monitor critical 65 and 45 nm processes such as ion implant, nitrided SiO2 gate dielectrics, NiSi, Cu/porous low-κ interconnects and MIM capacitors is highlighted in this paper. 


Hybrid (organic/inorganic) heterojunction device based on nano-crystallite structures of 2-(2, 3-dihydro-1,5-dimethyl-3-oxo-2-phenyl-1H-pyrazol-4-ylimino)-2-(4-nitrophenyl)acetonitrile (DOPNA) and ZnO thin films has been fabricated. The ZnO powder is prepared by the hydrolysis of zinc chloride in the presence of triethanolamine, the ZnO film is prepared by using spin coating technique, whereas the DOPNA thin film is deposited from the powder by the thermal evaporation technique. The formed nano-crystallite structures and lattice parameters of DOPNA and ZnO films have been determined. The optical absorbance of DOPNA and ZnO films are measured and the types of transitions as well as the optical band gap of the films are evaluated. The current-voltage characteristics of ITO/ZnO/DOPNA/Au heterojunction diode in dark and under illumination conditions have been investigated. The capacitance-voltage characteristic showed that the formed junction is of abrupt nature and the built-in potential is estimated. The solar cell parameters have been determined as 0.37 V for open circuit voltage, 1.04 mA for short circuit current, 0.43 for fill factor and 1.56% for power conversion efficiency.

Structure and diffusion of Ga and As ions in simulated liquid GaAs have been studied in a model containing 3000 ions under periodic boundary conditions via molecular dynamics simulation (MD). The microstructure of systems has been analyzed through partial radial distribution functions (PRDFs), coordination number distributions, bond-angle distributions and interatomic distances. We found that calculated data agree well with the experimental ones. Temperature dependence of these distributions was obtained. Caculations show that liquid GaAs model with a real density at 5.3176 g cm-3 has a distorted tetrahedral network structure with the mean coordination number ZAs-Ga ≈ 4. Diffusion constant D in system has been calculated over temperatures ranged from 5000 K down to 1500 K. Calculations show that the temperature dependence of the diffusion constant D shows an Arrhenius law at relatively low temperatures above the melting point and it shows a power law, D ∼ (T - Tc)γ, at higher temperatures.


The characterization of the BPDA/PDA polyimide (PI) at high temperature up to 400 °C, thanks to dielectric relaxation spectroscopy (DRS) in the 10-1 Hz to 106 Hz frequency range, allows the determination of the dc electrical conductivity (σdc). In such a high temperature range, the dielectric spectra are modified by the extrinsic electrode polarization phenomenon (EP) response. A model is proposed which coupled to the DRS results allows evidencing and quantifying the effect of the EP. The proposed method gives a simple way to determine the intrinsic σdc values from the effective ac dielectric response, improving the accuracy and reducing the duration of measurement. For BPDA/PDA PI, the resulting σdc values range from 4 × 10-11 to 8 × 10-6 Ω-1 m-1 for temperatures between 200 and 400 °C, with an activation energy of the conduction phenomenon of 0.55 eV.

The generation of white light from CdS nanoparticles (NPs) illuminated by UV-LED is presented. The synthesis of CdS nanoparticles from the reaction of CdCl2 and the sulfur dissolved in oleylamine in 1:2 mole ratio was used in the preparation of CdS nanocrystalline. The PMMA film doped with CdS nanoparticles was prepared. The generation of white light was found from illumination of the CdS/polymer composite film by UV-LED of power 5 mW at λ = 385 nm. The white light generation mechanism was explaining depending on mixing colors from the illuminated CdS nanoparticles. The surface levels formed in the CdS optical energy band due to nanostructure was estimated from Poisson equation designed for this state. The chromaticity coordinates of the generated white light was measured by the help of photoluminescence (PL) spectrum and the correlated color temperature was found to be about 4000 K.


An infrared heat reflecting multilayer thin film filter comprising alternate layers of ZrO2 and SiO2 has been modeled and prepared on a BK7 glass substrate using RF-magnetron sputtering. Initially, the individual films of the used materials have been characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) for structural and surface quality prior to the deposition of multilayer structure. Spectral analysis showed that the filter has an average transmission of greater than 90% in 450 to 700 nm range and less than 2% in 700-1100 nm band fulfilling the design requirements. The XRD study of multilayer structure showed few peaks of ZrO2 along with a solitary peak for SiO2 indicating some crystallinity for ZrO2 layers in the structure. Hardness analysis showed that the initial phase of the indentation is predominantly ductile with gradual transition in behaviour from ductile to brittle with increased penetration. Interface analysis of multilayered structure was carried out by Rutherford back scattering using Tandem 5 MeV ion accelerator, showed that interfaces formed in the multilayer structure are sharp and no substantial evidence of interlayer diffusion or mixing at the interfaces.


Plasma nitriding of aluminium in a 50 Hz pulsed-dc glow discharge is studied for different ion-current densities (2.0-5.0 mA cm-2) by keeping the corresponding discharge parameters such as treatment time, chamber pressure, substrate temperature and gas composition same. The treated samples are analysed for changes induced in surface properties using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Vickers's micro-hardness testing. XRD showed the downshift in the original diffraction peak corresponding to (111) plane reflection along with the emergence of new diffraction peak corresponding to (220) plane reflection, confirming the N-diffusion into existing Al-lattice and formation of AlN compound. Surface hardness is significantly improved which might be attributed to the diffusion of nitrogen and compound layer formation.

Electric-field-induced magnetization (EIM) resonant characteristics were investigated in bilayered and trilayered composites. The length resonant EIMs were inspired in both symmetrical and asymmetrical composites and the EIM coefficients were relative to the thickness ratio between PZT and Terfenol-D. The bending resonant EIMs were observed in the bilayered and asymmetrical trilayered composites besides the length resonant EIMs. The symmetrical composites only produced weak bending resonant EIMs even though the composites with two PZT layers connected in parallel enjoyed a much strong electromechanical bending resonance. The results are helpful for the future design of magnetoelectric devices.


Electrical conductivity measurements of pyronine G(Y) were performed as a function of both temperature (303–443 K) and frequency (50 Hz–550 kHz). The frequency dependence of ac conductivity is well represented by the form ωs. The values of exponent, (s) decrease from 0.98 at 303 K to 0.67 at 403 K. The temperature dependence of both ac electrical conductivity and the exponent (s) reveals that the ac conduction is due to the correlated barrier hopping (CBH). The dielectric constant, ε1(ω), and dialectic loss, ε2(ω), have been determined for bulk pyronine G(Y). Both ε1(ω) and ε2 (ω) decrease by increasing frequency and increase by increasing temperature.

We describe a new technique for the fabrication of point contacts using a focused ion beam (FIB) patterning. After sample coverage with a thin insulating layer (SiO), an FIB is used to mill a 100-nm-diameter hole through the insulator. Electrical contact to the sample is then made in-situ by filling the hole with a metal (Pt) using the ion beam assisted chemical vapor deposition capability of our FIB system. We have demonstrated the use of two such contacts (as an emitter and collector) in a transverse electron focusing (TEF) experiment. The contacts were made to a single crystal of bismuth, ballistic electrons were injected into the crystal through the emitter contact and then focused onto the collector by a magnetic field. We see the expected voltage peaks at the collector as a function of the applied magnetic field. Temperature dependent TEF measurements provided direct information about relaxation time of conduction electrons.

The nonuniform energy density distribution of laser pulses leads to nonuniform pressure distribution of sound field on photoacoustic effect, and photoacoustic image would be distorted at the edge of the absorbed optical energy deposit area. In this paper, a new method for compensating the sound field pressure and correcting the photoacoustic image is reported and testified. Distribution of the photoacoustic pressure was measured with a phase-controlled focus array transducer, and the theoretic function of the photoacoustic pressure was extracted by fitting the distribution curve. The compensation weight factor of the photoacoustic pressure defined as a reciprocal of the theoretic function. Photoacoustic images of a simulation sample and an in vivo mouse brain were reconstructed by correcting with the pressure compensation weight factor. The experimental results showed that this method can uniform the contrast distribution and correct the edge distortion of the PA image, suggesting the potential application in vascular imaging.


Various thermoplastic and thermo-set based polymers, blended with acetylene carbon blacks and graphite fillers to form electrically conductive polymers, were investigated to determine the switching mechanism under high power short-circuit fault conditions. Presently, a positive temperature coefficient (PTC) effect is the accepted switching mechanism for low power overcurrent devices. However, for high power, distribution level devices, this mechanism has been assumed to be the same under high fault conditions. This work proposes another possible switching mechanism responsible for a steep change in resistance under high power faults. The proposed mechanism of resistance change comes, not from the PTC change in the material, but rather from the vaporization of the conducting polymer contact areas at the polymer/electrode interface. A comparison between low power polypropylene based devices with a positive temperature coefficient (PTC) effect (thermal expansion of the polymer bulk) and high power devices was done to support this theory. A model was developed along with numerous short-circuit tests to support this theory. Modifications with e-beam irradiation were made to alter the PTC characteristics of thermoplastics but had little effect on high fault short-circuit switching. Also, numerous short-circuit testing on thermo-set based materials without any PTC transition still switched under high fault currents. These all supported the proposed theory that switching, under high fault currents, was from vaporization of the contact areas at the polymer surface rather than thermal expansion in the bulk of the conductive polymer as previously accepted.

In this article we have shown that it is possible to use transmission, absorption and reflection spectroscopic data of KClxBr1-x single crystals for the TL (Thermo Luminescence) dosimetry purposes in the spectral range of 250-750 nm. The effects of gamma radiation on KClxBr1-x single crystals were investigated by radiating the samples with a 60Co source and studying the reflection and absorption spectra. Six doses of gamma radiation of 145, 300, 450, 600, 750 and 900 Gy were examined. The absorption peak height in the spectral region of 560-580 nm is in a direct relationship with the gamma radiation doses up to about 800 Gy, in which saturation starts to occur. The intensities of the color centers in mixed crystals are different by their combination ratios of the components contents. According to the reflection and transmission data, the absorption spectra can be calculated and a calibration curve sketched.

This paper analyses corona discharge in ambient air flow associated with laboratory-scaled wire-to-plate electrostatic precipitator (WPESP). The corona discharge is analysed by a combined iterative computational technique based on the finite element method (FEM) and charge simulation method (CSM). The phenomenon is mathematically described by Maxwell's equations in differential form. A finite element method is used to solve the Poisson's equation and the charge simulation method is used to satisfy the current continuity condition. Measurement method of the positive dc corona current density and electric field, taking into account the air flow velocity, has been introduced. The computed results are compared with experimental results to test the effectiveness of this approach.

Conductive ceramics have widespread use in many industrial applications. One important application for such materials is electrical contact technology. Over the last few years, a new class of nanocomposite ceramic thin film materials has been developed with contact coatings as one key objective. This family of materials has proven to combine the favorable contact properties of metals, such as low electrical and thermal resistivity, and high ductility, with those of ceramics such as low friction and wear rate, high chemical integrity and good high-temperature properties. Furthermore, it is also found that the tribological properties of such materials can be tailored by alloying thus creating a triboactive system. The technology is now industrialized, and a practical example of a contact system utilizing a nanocomposite coating for improved performance is given.

Fretting remains a major cause of connector failure and can impair reliability in complex systems like automotive applications. Tin is particularly previous to fretting phenomena; we report here the first results of an analysis of tin and lubricated tin contacts, based on the analysis of the friction or slip regimes and the electrical behaviour. Lubricant properties are analysed in terms of friction behaviour and the effect of a special additive is examined.

The effect of a uniformly distributed, immobile, charged particle background on the stationary states of a plasma diode with beam electrons is studied. Whereas a positively charged particle background results in an increase of the space-charge limit of the electron current across the diode and brings in new branches of equilibria, a negatively charged background decreases the current up to zero current level due to a complete reflection of beam electrons within the diode region. This effect can be used for the design of fast switches.

In this paper, an eddy-current formulation is used to determine the transmission-line parameters of a machine winding. It is shown that this formulation covers a broader frequency range than the commonly used low-frequency magnetostatic and high-frequency magnetodynamic approximations. The eddy-current formulation, however, suffers from large computation times and may lead to severe inaccuracies if the finite-element mesh does not resolve the skin depth, a modelling concern that does not exist for the traditional formulations. The three finite-element models are compared according to the accuracy of the resulting transmission-line model applied to the winding of a permanent-magnet synchronous machine.


In this paper, we extend corresponding theory which can only deal with thin medium based on thin sheet approximation to a new area which can deal with thick medium with gain and loss. An analytical expression for the location and the peak intensity of the hot-image in the case of thick nonlinear medium with gain and loss are deduced by using propagation matrix method. In order to confirm our analysis as a reliable tool to forecast the hot-image damage risk, we provide some numerical results to verify its validity. The predictions of the theory are found to be in good agreement with the numerical simulations. The theoretical analysis can be used for forecasting the intensity and location of the hot-image. It can provide rules for estimating the damage risk of the hot-image and warn us of the critical areas that may be vulnerable to the hot-image.

The presented study deals with the influence of the contacts materials on the evolution of the arc in low voltage circuit breakers. The commutation from the mobile contact onto the electrode is especially investigated in order to improve the breaking device performances. Hence, to preserve the qualities of the contact, the arc must leave this area as soon as possible. To undertake this study, several diagnostics are implemented. A measuring device is composed of magnetic induction sensors located outside the chamber. It allows the determination of the position and the volume of the arc during the breaking. Optical (ultra-speed camera) and electrical measurements are also performed with the technical support of Schneider Electric. Different current values (assumed peak current of 3 kA, 8 kA and 12 kA) and different natures of materials composing the electrical contacts have been tested. Copper contacts, different contacts on silver base obtained with different processes have been used. Experimental results show the influence of these various parameters on the arc volume and on the transfer of the arc towards the quenching chamber. Indeed, different dynamic behaviors are observed during the current transfer phase.