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An atomic and electronic structure of the bulk and thin-film morphologies of ZnO were modified using pulsed Bi-ion implantation (1x1017 cm-2 fluence, 70 min exposure under Bi-ion beam, EBi+ = 30 keV, pulsed ion-current density of not more than 0.8 mA/cm2 with a repetition rate of 12.5 Hz). The final samples were qualified by X-ray photoelectron core-level and valence band mapping spectroscopy applying ASTM materials science standard. The spectroscopy data obtained was discussed on the basis of DFT-models for Bi-embedding into ZnO host-matrices. It was established that in the case of direct Bi-impurities insertion into the employed ZnO-host for both studied morphologies neither the only "pure" Bi2O3-like phase nor the only "pure" Bi-metal will be preferable to appear as a secondary phase. An unfavorability of the large cluster agglomeration of Bi-impurities in ZnO-hosts has been shown and an oxygen 2s electronic states pleomorphizm was surely established., 20 pages, 8 figures, 2 tables, accepted to Appl. Surf. Sci

H+ emission from the sharpening glass fiber was successfully observed. Here, ion current density and chemical functionalization via ion irradiation are presented.

The reduced-scale model of HVDC transmission lines in the laboratory is widely used to investigate the ionized fields. This paper is aimed at analyzing impact factors of the ion-current density measurement system based on Wilson plates in the laboratory. Both experimental and numerical simulation methods are used to obtain the characteristics of the measurement system. The results show that measurement data can be calibrated with different Wilson plates, and suitable parameters are proposed in this paper to meet the requirement of measurements. The measurement system described in this paper can be used in other similar applications.

Проведены исследования величины объема нанокластера и глубины его залегания в зависимости от энергии, заряда и сорта ионов (B⁺, N⁺, C⁺, Al⁺, V⁺, Cr⁺, O⁺, Ni⁺, Zr⁺, Mo⁺, Hf⁺, W⁺, Ta⁺, Pt⁺), что позволяет определить состав ионов, их энергии и заряды для получения наноструктур в требуемом слое, а с учетом необходимой плотности ионного тока оценить практически все технологические параметры для получения слоя требуемой толщины и физико-механических характеристик в титановом сплаве ВТ-1. Researches volume values nanocluster and its depth, depending on the energy, charge and the type of ions (B⁺, N⁺, C⁺, Al⁺, V⁺, Cr⁺, O⁺, Ni⁺, Zr⁺, Mo⁺, Hf⁺, W⁺, Ta⁺, Pt⁺), which allows to determine the composition of the ions, their energy and charges for a desired nanostrutkur layer, and with the required density of the ion current estimate virtually all process parameters required for the layer thickness and the physical and mechanical characteristics of the titanium alloy.

Приведены особенности обработки отверстий комбинированным осевым инструментом. Предложен алгоритм выбора структуры комбинированного осевого инструмента для реализации технологического процесса обработки совокупности отверстий, основанный на анализе их конструктивно-технологических характеристик и увеличении концентрации технологических переходов. Предложена математическая модель, позволяющая описать структуру комбинированного осевого инструмента и принцип работы его ступеней. Researches volume values nanocluster and its depth, depending on the energy charge and the type of ions (B +, N +, C +, Al +, V +, Cr +, O +, Ni +, Zr +, Mo +, Hf +, W +, Ta +, Pt +), which allows to determine the composition of the ions, their energy and charges for a desired nanostructure layer, and with the ion current density required to obtain substantially all of the process parameters to obtain the desired layer thickness and physical-mechanical characteristics in the magnesium alloy.

A physicochemical model for the reactive magnetron sputtering of a "hot" target is described in this paper. The system consisting of eight algebraic equations was solved for a tantalum target sputtered in an O2 environment. It was established that the hysteresis effect disappears with the increase of the ion current density.

The Radio Frequency (RF) negative hydrogen ion source prototype has been chosen for the ITER neutral beam injectors due to its optimal performances and easier maintenance demonstrated at Max-Planck-Institut für Plasmaphysik, Garching in hydrogen and deuterium. One of the key information to better understand the operating behavior of the RF ion sources is the extracted negative ion current density distribution. This distribution - influenced by several factors like source geometry, particle drifts inside the source, cesium distribution, and layout of cesium ovens - is not straightforward to be evaluated. The main outcome of the present contribution is the development of a minimization method to estimate the extracted current distribution using the footprint of the beam recorded with mini-STRIKE (Short-Time Retractable Instrumented Kalorimeter). To accomplish this, a series of four computational models have been set up, where the output of a model is the input of the following one. These models compute the optics of the ion beam, evaluate the distribution of the heat deposited on the mini-STRIKE diagnostic calorimeter, and finally give an estimate of the temperature distribution on the back of mini-STRIKE. Several iterations with different extracted current profiles are necessary to give an estimate of the profile most compatible with the experimental data. A first test of the application of the method to the BAvarian Test Machine for Negative ions beam is given.

Accurate measurement of ion current density and ion energy distributions (IEDs) is often critical for plasma processes in both industrial and research settings. Retarding field energy analysers (RFEAs) have been used to measure IEDs because they are considered accurate, relatively simple and cost effective. However, their usage for critical measurement of ion current density is less common due to difficulties in estimating the proportion of incident ion current reaching the current collector through the RFEA retarding grids. In this paper an RFEA has been calibrated to measure ion current density from an ion beam at pressures ranging from 0.5 to 50.0 mTorr. A unique method is presented where the currents generated at each of the retarding grids and the RFEA upper face are measured separately, allowing the reduction in ion current to be monitored and accounted for at each stage of ion transit to the collector. From these I–V measurements a physical model is described. Subsequently, a mathematical description is extracted which includes parameters to account for grid transmissions, upper face secondary electron emission and collisionality. Pressure-dependent calibration factors can be calculated from least mean square best fits of the collector current to the model allowing quantitative measurement of ion current density.

Optimization of SNMS depth profiling using the direct bombardment mode (DBM) is possible by improvement of the ion current density distribution, reduction of bombardment energy and independent choice of current density. A model for primary ion extraction is presented and ion current density distributions have been calculated for different sample holder arrangements. Using the simulation procedure optimal extraction conditions can be predicted for conventional arrangements and suggestions for new ones can be made. The best depth resolution has been obtained using a new extraction arrangement with an additional aperture.

Six routinely packaged commercially pure titanium dental implants (three commercial brands) were analysed using secondary ion mass spectrometry to examine the outermost surface layer. The aim of the analysis was to compare the surface purity (99.95%) of the implants with the substrate metal, common to all three brands. The use of a low primary ion current density provided a nominal protection limit of 0.01% or 100 p.p.m. All the implants examined had extremely pure surfaces. However, only one brand of implant had an ultraclean oxide surface in relation to the substrate.

It is well-known that quantitative analysis of major elements by SIMS is generally difficult because of the matrix effect. In the present paper we examined some basic problems of the major element analysis of CdxHg1-xTe (CMT) which is known to be easily damaged by various kinds of beams. It was shown that the matrix effect in quantification can be reduced by detecting postionized monoatomic ions for O2+ and Ar+ primary beams. In the case of Cs+ bombardment, detection of the cationized molecular ions, which are formed via one kind of post-ionization process, also proved to be effective. In all the cases, good linear relationships between the secondary ion intensity and the primary ion current density were obtained in the log-log plot. The intensity decrease of Hg+, however, was observed along with depth profiling of the bulk sample. This phenomenon was correlated with the morphological changes caused by ion irradiation.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

The development of AIII–BV semiconductor surfaces exposed to ion-beam irradiation in the ion energy range from 100 to 1000 eV and the ion current density of 1 mA/cm2 (max) is investigated. The ion-beam etching with an ion energy of 1 keV results in sharp cones and needles on the semiconductor surface due to the surface contamination and unevenness. Etching with ion-beam energies in the order of 300 eV and with etch rates higher than 1000 A/min produces relatively even GaAs surfaces. In case of reactive gases (i.e. CCl2F2 and the mixture of CCl2F2+Ar) ion-beam etching results in significantly higher etch rates; however, the mask residue contains Cl and F. In studies on the ion-beam resistance of organic masks selectivities as high as 13:1 for the photoresist CM-79 with an ion energy of 180 eV and an ion current density of approximately 0.3 mA/cm2 were achieved.

Conventional practice in the design of corona discharge electrodes for electrostatic precipitators tends toward those having a relatively low corona Inception voltage. But the theory indicates that maximal electric field strength is beneficial to both charging and collection of particles. Only those particles smaller than about 0.2 μm diameter are more readily charged by increasing the ion current density instead of the electric field strength. Tests carried out on high-resistivity fly ash In a large pilot system (30,000 acfm) comparing performance of 3/8-in. diameter wires with more nearly conventional 1/8-in. wires resulted in substantially superior performance for the larger electrodes

Established techniques of making thin foils of non-metallic materials are reviewed briefly and their inadequacies outlined. The preparation of foils by sputter-etching is described and the effects on the sample of ion current density, and angle of ion incidence are discussed. Results on specimens of ceramics, glasses and minerals are presented. From these it is concluded that sputter-etching is a valuable and nearuniversal thinning technique for non-metals.

and transport to the tokamak plasma strongly depends on the divergence and the deflection angle of each single beamlet with respect to its ideal trajectory. In fact, a very narrow window is available for the particle beam to pass through the neutralizer panels and the duct reaching the tokamak plasma. For this reason, beam optics quality is one of the key requirements in multi-stage multi-beamlet negative ion accelerator, such as the high power Heating Neutral Beam injectors for ITER and JT-60SA. In the framework of the collaboration established between Consorzio RFX (Padova, Italy) and QST (Naka, Japan) experimental campaigns have been organized on the Negative Ion Test Stand (NITS) in Naka employing an ITER-like multi-beamlet configuration [1]. These campaigns were intended to: o Test and optimize new solutions for cancelling the undesired ion deflection caused by the transverse magnetic field required for suppressing the co-extracted electrons [2]. o Better understand the physics underlying the extraction of single beamlets in the initial part of their trajectories, close to the ,,meniscus" region. o Validate and improve the numerical codes used for the accelerator design Although it was not possible to explore all the intended parameter space due to power supply limitations, the experiments carried out in 2016 and 2017 allowed to successfully achieve the first most important (engineering) objective and to provide bases for the achievement of the other two (physics) objectives, which will be completed during new already planned activities and collaborations.

Les mecanismes de gravure du silicium en plasma de SF6 sont etudies aux basses pressions et aux faibles energies ioniques dans un Plasma Multipolaire Micro-onde. L'analyse des profils obtenus sur des motifs graves et celle des produits de reaction detectes par spectrometrie de masse montre comment la vitesse de gravure et l'anisotropie evoluent en fonction de la pression. En particulier, on observe une transition regime isotrope-regime anisotrope pour une valeur critique de la pression. Pour expliquer les resultats experimentaux obtenus, une nouvelle interpretation des mecanismes de surface intervenant en gravure plasma est proposee. Afin de rendre coherents les modeles existants, il est necessaire de leur adjoindre trois hypotheses supplementaires, a savoir : i) existence de fortes interactions repulsives entre atomes de fluor adsorbes proches voisins; ii) diffusion en surface des especes adsorbees ; iii) modele d'adsorption multicouches pour le systeme Si/F. Le traitement analytique du modele met en evidence que la vitesse de gravure est limitee par la pression partielle de fluor atomique dans le plasma, tandis que l'anisotropie est controlee par la densite de courant ionique.

Progress is reported in research aimed at measuring and defining the electrical environment in the vicinity of HVDC transmission lines, predicting this electrical environment for any HVDC line design, and providing information on this electrical environment to bio-effects researchers. Methods for measuring ground-level electric field and ion current density are described and data from electrostatic field measurements for lines at 950, 1050, and 1200 kV are presented. (LCL)

This final report describes both the engineering development of a DC bioeffects test enclosure for small laboratory animals, and the biological protocol for the use of such enclosures in the testing of animals to determine possible biological effects of the environment associated with HVDC transmission lines. The test enclosure which has been designed is a modular unit, which will house up to eight rat-sized animals in individual compartments. Multiple test enclosures can be used to test larger numbers of animals. A prototype test enclosure has been fabricated and tested to characterize its electrical performance characteristics. The test enclosure provides a simulation of the dominant environment associated with HVDC transmission lines; namely, a static electric field and an ion current density. A biological experimental design has been developed for assessing the effects of the dominant components of the HVDC transmission line environment.