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The effect of Al dust particles on glow discharge regions, dischargevoltage, discharge current, plasma potential, floating potential,electron density and electron temperature in planar magnetronsputtering device has been studied experimentally. Four cylindricalLangmuir probes were employed to measure plasma parameters atdifferent point on the radial axis of plasma column. The resultsshows the present of Al dust causes to increase the discharge voltageand reduce the discharge current. There are two electron groups inthe present and absent of Al dust particles. The radial profiles ofplasma parameters in the present of dust are non- uniform. Thefloating potential of probe becomes more negatively while theplasma potential becomes positive when the dust immersed intoplasma region. The electron density increases in the present of dustparticle which lead to decreases the electron temperature.

The mass-to-charge ion composition of a planar magnetron discharge plasma has been investigated. The measurements used a modified quadrupole mass-spectrometer and a time-of-flight spectrometer. The experiments were carried out on a copper magnetron target. Argon was used as a working gas. The operating pressure was 0.15÷1.3 Pa. The discharge current was 1÷20 A with a pulse duration of 30÷50 μs. The influence of main operating parameters (discharge current and working gas pressure) on mass-to-charge composition of plasma ions was measured. The mass-to-charge composition of plasma ions in the axial direction was measured as a function of working pressure. Plasma electron temperature was measured and its effect on the mass-to-charge composition of magnetron plasma ions was estimated.

Incoherent Thomson Scattering (ITS) is one of the most reliable techniques for determining electron properties inside a plasma. Key information (electron density, temperature (more generally, the EEDF), and drift velocity) can be determined from the analysis of the intensity and spectral distribution of light of a laser pulse scattered by free electrons. In contrast to many conventional techniques, it is non-perturbative, gives access to spatiotemporally-resolved information, and can be applied in magnetized plasma regions. Yet ITS implementation in low-temperature plasmas poses a particular challenge due to the low plasma densities involved.This thesis focuses on the development and application of a new ITS diagnostic.Traditional diagnostics have commonly used triple grating spectrometers to filter the stray light signal (from Rayleigh scattering and laser reflections) in order to allow detection of the Thomson-scattered signal from electrons. Instead, this work uses a recently-commercialized notch filter for stray light reduction. This approach enabled the development of a diagnostic with notable sensitivity and compactness.This diagnostic, named THETIS, was used to gain insights into three low-temperature, magnetized plasmas sources operating at low pressure.A planar magnetron was studied in continuous (DCMS) and pulsed (HiPIMS) regimes, with these investigations allowing the extraction of spatial and temporal profiles of electron properties. This study focused on the influence of the gas type, repetition rate, and magnetic field intensity.A ECR ion source was also studied in pulsed and continuous regimes. The influence of the gas type, pressure and power were investigated. In addition to the study of the dynamics of electron properties in pulsed operation, insights into species excitation and ionization were gained from the analysis of the plasma emission.Lastly, electron properties along radial and azimuthal directions in Hall thrusters in “standard” and “magnetic shielding” configurations were investigated. The influence of the magnetic field intensity, configuration, and direction were investigated, as well as the discharge power and voltage. This work revealed not only the presence of anisotropies in electron properties, but also high electron temperatures in magnetized regions of the thruster plasma and the presence of strongly non-Maxwellian EEDFs in such regions.The information on electron properties, and the accompanying physical insights obtained in this work, contribute to current understanding of these plasmas and provides a new path forward for their modeling and development., La diffusion Thomson incohérente (DTI) est l’une des techniques les plus fiables pour sonder les propriétés électroniques d’un plasma. Des informations clés (densité, température, vitesse de dérive et FDEE) peuvent être obtenues par analyse de l’intensité et de la distribution spectrale de la lumière diffusée sur les électrons libres. Cette technique est non perturbative, permet de bonnes résolutions spatiotemporelles et peut être appliquée dans des régions magnétisées du plasma. Pourtant, l’implémentation de diagnostiques de DTI dans les plasmas bas températures pose un défi en raison des faibles densités plasma.Cette thèse se concentre sur le développement et l’application d’un nouveau diagnostic DTI. Un nouveau type de filtre notch est utilisé pour atténuer la lumière parasite (provenant de la diffusion de Rayleigh et des réflexions laser) et faciliter la détection du signal de diffusion Thomson. Ce composant a permis le développement d’un diagnostic, nommé THETIS, à la fois sensible et compact pour étudier trois sources plasmas magnétisés basse température fonctionnant à basse pression.Un magnétron plan a été étudié en régime continu (DCMS) et pulsé (HiPIMS), ces investigations ont permis l’extraction de profils spatiotemporels des propriétés électroniques. Cette étude s’est concentrée sur l’influence du type de gaz, du taux de répétition et de l’intensité du champ magnétique.Une source d’ions ECR a également été étudiée en régime pulsé et continu. L’influence du type de gaz, de la pression et de la puissance a été étudiée. En plus de l’étude de la dynamique électronique en régime pulsé, l’analyse de l’émission du plasma a permis de suivre les processus d’excitation et ionisation.Enfin, les propriétés électroniques selon les directions radiales et azimutales de propulseurs à effet Hall dans les configurations “standard” et “écrantage magnétique” ont été étudiées. L’influence du champ magnétique et des conditions de décharge ont été étudiées. Ce travail a révélé non seulement la présence d’anisotropies dans les propriétés des électroniques, mais également la présence de forte température dans les régions magnétisées du plasma du propulseur couplées à des FDEE fortement non maxwelliennes.Les résultats des travaux de cette thèse contribuent à la meilleure compréhension de ces plasmas et ouvrent une nouvelle voie pour leur modélisation et développement.

Mathematical model for temperature fields calculation in targets of magnetron sputtering systems is described. The paper shows the main ways in which the power supplied to the discharge is removed. The results of numerical simulation of the spatial temperature distribution of a magnetic target are presented. The paper also shows the results of numerical simulation, which allow to link the input power and the shape of the target with the distribution of its temperature. For the obtained temperature distributions magnetic induction distributions are calculated taking into account the loss of magnetic properties of a material when its temperature exceeds the Curie point.

Tungsten-trioxide (WO3) films were deposited using two types of sputtering systems: a planar magnetron sputtering system and a facing-target sputtering (FTS) system. The structure and gasochromic properties of the resulting films were compared, and film uniformity and gasochromic properties were found to be significantly improved when using FTS because the incidence of high-energy negative oxygen ions on the substrate during sputtering was significantly suppressed. The authors confirmed that the deposition rate of WO3 films increased by hundreds of times with an increase of the sputtering voltage from 500 to 800 V in the FTS system, and a deposition rate above 100 nm/min was easily achieved. The authors clarified that the deposition rate of the WO3 film strongly depends on the sputtering voltage under the condition of a constant sputtering current.Tungsten-trioxide (WO3) films were deposited using two types of sputtering systems: a planar magnetron sputtering system and a facing-target sputtering (FTS) system. The structure and gasochromic properties of the resulting films were compared, and film uniformity and gasochromic properties were found to be significantly improved when using FTS because the incidence of high-energy negative oxygen ions on the substrate during sputtering was significantly suppressed. The authors confirmed that the deposition rate of WO3 films increased by hundreds of times with an increase of the sputtering voltage from 500 to 800 V in the FTS system, and a deposition rate above 100 nm/min was easily achieved. The authors clarified that the deposition rate of the WO3 film strongly depends on the sputtering voltage under the condition of a constant sputtering current.

At the Danish National Space Center (DNSC), a planar magnetron sputtering chamber has been established as a research and production coating facility for curved X-ray mirrors for hard X-ray optics for astronomical X-ray telescopes. In the following, we present experimental evidence that a collimation of the sputtered particles is an efficient way to suppress the interfacial roughness of the produced multilayer. We present two different types of collimation optimized for the production of low roughness curved mirrors and flat mirrors, respectively.

We present a model for the DC planar magnetron discharge that separates and simplifies as much as possible the different processes occurring. A crucial part of a magnetron discharge simulation is the motion of the high-energy electrons and the resulting ionisation. This part is usually done by Monte Carlo calculations. We developed an alternative, much faster approach by considering the discharge as being built up by arch-shaped regions. Consequently, the model requires little computing time and, hence, allows to investigate the dependence of the discharge on different external parameters over a wide range. In this article results obtained by our model for calculating the voltage dependence of the cathode sheath and of the erosion profile at constant pressure are shown.

The Multi-Frequency Recirculating Planar Magnetron (MFRPM) is a type of Recirculating Planar Magnetron (RPM) designed for tunable or simultaneous oscillation at more than one primary frequency. Like the RPM, the MFRPM is a crossed-field, high power microwave (HPM) source that integrates the design advantages of the RPM with the added benefit of producing multiple frequencies using a single HPM device. Design of an L-S-band prototype is underway for a 0.2 T axial magnetic field and a -300 kV voltage pulse.

Thin TiNi films (17 - 5 microns thick) deposited from a planar magnetron source onto a 6.35 mm diameter centerless ground rod (average surface roughness is about 1 micron) and onto a polished one (average surface roughness is about 0.02 micron) have been characterized. The film deposited onto a ground rod breaks very easily and can be removed from the substrate only in small pieces. It was found that the external surface of the film replicates all the imperfection of the original ground surface. The film has a plate-like grain structure with the plates stacked across the grinding marks aligned along them and perpendicular to the film surface. These plates have very poor cohesion between each other, and film easily brakes apart along the grinding marks. The film deposited onto a polished rod is strong enough to be pulled from the surface cut into samples 25x1 mm, and mechanically tested. The grain structure, external surface, roughness, and mechanical properties of the film were found to be dependent on the incident angle while the transformation characteristics of the film are almost independent of it.

The article reports on structure and hardness of NiCr–N films prepared by dc reactive magnetron sputtering of NiCr (80/20 wt. %) target in a mixture of Ar and N2 on glass and 15 330 steel substrates at room temperature using a round planar magnetron of diameter 75 mm. It was found that while pure NiCr films are polycrystalline, an addition of nitrogen into the film reduces a grain size d and makes it possible to form nanocrystalline NiCr–N films. The hardness HV of the NiCr–N film increases with decreasing grain size d but only down to about 7 nm. For grains smaller than 7 nm the hardness HV decreases.

The article by Villamayor et al. was published with the incorrect volume number. The correct volume number is Volume 1601. The Materials Research Society and Cambridge University Press apologize to the authors for this error. The correct version of the article follows this notice.

Langmuir probe measurements have been carried out in a positive column discharge of a planar magnetron with a titanium target. In this work concentration and temperature of electrons is measured in positive column of magnetron discharge with Langmuir probe. Concentration of electrons is found to be on the level of 1016 m-3 at a notable distance (over 200 mm). Two groups of electrons exist: «cold» and «hot» with average temperature of 16 000 and 41 000 K respectively. Dependence of discharge parameters on working gas pressure is measured.

In order to understand the discharge mechanism of crossed electrical and magnetic field discharge, a fine probe is inserted into the planar magnetron discharge, and the potential distribution and its characteristics are measured. In the positive space charge region (PSC), a sharp cathode fall is observed. On the other hand, it is found in the negative space charge region (NSC) that the space potential Ps is given by Ps= Vd (x/Dst )n, where Vd, x, Dst and n are the discharge voltage, the distance from the cathode surface, the distance between the anode and the cathode, and the slope, respectively. The slope n is about 1.7 in the pressure range of 10-310-2 Pa. In addition, the slope n is little affected by the pressure P, Vd and Dst, and is kept in the range of 1.61.8.

In order to provide a guiding principle for designing a magnetron sputtering cathode, the relationship between the erosion shape of the target and the relative electron density in the space above the target is described based on a computer simulation of electron motion. Since the most important factor is the magnetic field, the electron motion is calculated using an approximate field expression derived from the measured magnetic field. The actual erosion shape of a rectangular planar magnetron cathode, where the target is 120×560 mm in size, was compared with the calculation. The actual erosion shape coincides with the calculated relative electron density. In particular, in the area where glow discharge plasma is linear, the calculated half-value width of the relative electron density and the actual erosion halfdepth width on the nonmagnetic target are 14.5 and 15.0 mm, respectively. On the magnetic target, both are 6.0 mm.

The physical and mechanical properties of pulsed rotating cylindrical magnetron sputter-grown tantalum nitride (TaN) thin films were studied. Initially, films were grown at ambient substrate temperature by varying the reactive (N 2) to sputter (Ar) gas ratio (R) at a constant pulsing frequency of the target power (100 kHz). The results were compared with planar magnetron-grown TaN samples. The R C-Mag. grown thin films have properties nearly similar to the high temperature (300 �C) dc planar magnetron sputter deposited samples. In comparison to the planar magnetron deposition, the progression of the phase composition occurs over a wider range of R in the pulsed R C-Mag. deposition. These observed differences for R C-Mag. deposition are attributed to the increased glancing angle deposition of adatoms and pulsing of the target power. To study the effect of pulsing frequency of the target power in R C-Mag., the films were also grown at different frequencies at a fixed R (0.1). With the increase in frequency, the mechanical hardness increased up to 50 kHz and started decreasing beyond 50 kHz. The observed changes in the mechanical hardness are attributed to the increase in stress and to the formation of increased polycrystalline understoichiometric TaN phases. � 2009 American Vacuum Society.

A high rate magnetron target of 110 mm dia has been designed and fabricated. It is operated in dc sputtering mode and its performance is evaluated by studying the glow discharge characteristics, deposition uniformity and erosion area.

W/C multilayer mirror for 4.47nm had been fabricated by planar magnetron sputtering. Using small angle X-ray, transmission electon microscopy cross-section analysis and 4.47nm absolute reflectivity measurement techniques, the structrure and optical properties of this multilayer had been characterized.

ZnO films with an excellent c-axis orientation, transparancy, and surface flatness have been prepared by high deposition-rate rf planar magnetron sputtering. The optical waveguide loss for the TE0 mode of He-Ne 6328 A line is as low as 2.0 dB/cm in a 4.2 μm thick film without postsputtering treatment. Single-crystalline ZnO films have been grown epitaxial onto sapphire substrates in a ZnO-H2-H2O-O2 system. In this growth, water vapor and intermediately-sputter-deposited very-thin ZnO epitaxial layer are very important to grow ZnO films with an optically flat surface. The optical waveguide loss for the TE0 mode (6328 A) is as low as 0.7 dB/cm in a 2.57 μm thick film without postgrowth treatment.

A planar magnetron sputtering system for ferromagnetic targets is constructed for trial purposes and its DC discharge and sputtering characteristics and leakage magnetic field distributions are investigated for various currents of solenoid coil around a cylindrical pyrex chamber. Co-sputtering technique is proposed using a ferromagnetic or a non-magnetic cap-shaped target covered the SUS-304 cap for cooling a N-pole and a ferromagnetic washer-shaped target in this work. Four combinations of these targets are employed as follows : (a) Fe cap and Fe washer of 3 mm thickness, (b) Al cap and Fe washer of 3 mm thickness, (c) Al cap and Fe washer of 1 mm thickness and (d) Al cap and Ni washer of 1 mm thickness. The Ar gas pressures possible to discharge in the case of (a), (b) and (c) - (d) are 3-10 Pa, 0.2-3 Pa and 0.1-3 Pa respectively. And the deposition rates at 50W (DC power) in using (a), (b), (c) and (d) are 0.2-0.3 μm/h, 1.0-1.3 μm/h, 1.0-1.2 μm/h and 1.6-1.7 μm/h respectively.

The use of thick films in microelectronics has increased in an impressive way during the last years. In contrast to this, thin films have shown a less spectacular but nevertheless steady evolution which concerned mainly more efficient deposition methods (planar magnetron) as well as higher quality films and thus better components and circuits. The present paper aims at illustrating this by some selected examples.