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Dual-frequency oscillators have been used in many technical disciplines on account of the phase correlation between two output signals or the feasibility of producing beat wave effect. The mechanis...

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.

Calibrated microwave power measurements are presented for the Recirculating Planar Magnetron with Coaxial-All-Cavity Extraction (RPM-CACE). Experimental results are compared with computational predictions using the particle-in-cell code ICEPIC. The RPM-CACE was designed using extensive simulation and optimization to demonstrate the RPM concept, and was simulated to operate at 1.89 GHz and produce peak powers of $\sim 400$ MW at 50-70% efficiency. The experiment utilizes a novel coaxial extraction system to minimize the total diameter of the device.

The paper demonstrates the possibility to synthesize boron-containing coatings through magnetron sputtering of crystalline boron targets at a frequency of several hundred kilohertz, which is much lower compared to rf magnetrons, and presents research data on the surface profile of such coatings deposited in different reactive (air, N2, O2) gases.

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.

We have ascertained the influence of relativism on the processes and output parameters of a relativistic magnetron. The solution of the electron motion equations in a relativistic plane-geometry magnetron is presented. It is shown that these equations have the form corresponding to the nonrelativistic case, where one uses normalization for the static and high-frequency fields.

We have reported on the results of an investigation of the damping of longitudinal and shear hyperacoustic waves in Al/ZnO/Al/ZnO/YAG structures (lutetium-doped yttrium–aluminum garnet) based on ZnO piezo-active films with straight and inclined textures, which are synthesized at substrate temperatures T ≈ 25–400°C in an unbalanced planar magnetron sputtering system. It has been shown that anomalously high values of damping up to 45 dB is observed for the passage of acoustic waves through ZnO films with straight textures, which are grown at a substrate temperature T ≈ 200–300°C; an increase in the deposition temperature to T ≈ 400°C leads to a decrease in the introduced acoustic losses by 30–40 dB.

The subject of the master thesis is the extension of the measurement of plasma para- meters by the Langmuir probe in a system with a planar magnetron and a hollow cathode operating in pulse mode. The main tasks are to modify the measuring circuit to increase the maximum probe current and to put the USB oscilloscope into operation for data collection with higher resolution and higher sampling rate. Furthermore, the function of the entire device will be verified using test circuits and also by measuring the probe characteristics in discharges in a system with a magnetron and a hollow cathode in both continuous and pulse mode. 1

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.

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.

We have investigated the relationship between the presence or absence of Co (00.2) layer orientation and the characteristics of Cu filling into trenches. High-vacuum planar magnetron sputtering systems were used in the deposition of Co and Cu. Co-coated substrates with different Co (00.2) layer orientations were used in experiments on Cu filling into trenches of a width of 40 nm and aspect ratio 10. From the results of the Cu filling experiments, Cu filling into trenches was observed in substrates with Co (00.2) layer orientation. Similar Cu filling was also observed in trenches of a width of 20 nm and aspect ratio 4.5. We concentrated on lattice misfit between the Co (00.2) layer and the Cu (1 1 1) layer as the reason why Cu filling occurred in substrates with Co (00.2) layer orientation, and conducted a study from the capillary theory.

We investigated In-Ga-Zn oxide films deposited by two types of sputtering methods: planar magnetron and facing-target. In crystallinity, we found that silicon diffused from SiOx prevents crystallization regardless of the sputtering method. In electrical property, we found that mobility of films deposited by facing-target sputtering less depends on carrier concentration.

The subject of the bachelor thesis is the plasma diagnostics in the planar magnetron and in the hollow cathode system operating in the pulse mode, when the plasma is generated by DC pulses. The diagnostics method used will be the Langmuir probe. The aim of the thesis is the construction of the computer-controlled electronic measuring system and its assessment when measuring the parameters of argon discharge plasma in both systems with time resolution i.e. depending on time during one pulse period.

High power microwave sources that are capable of generating multiple frequencies simultaneously are desirable for applications such as counter electronics and vehicle stoppers. The Multi-Frequency Recirculating Planar Magnetron1, an adaptation of the Recirculating Planar Magnetron (RPM)2, has been developed at the University of Michigan to oscillate at 1-GHz as well as 2-GHz. Driven by a -300 kV, $0.3- 1.0 \mu \mathrm {s}$ voltage pulse from MELBA-C, this device has generated peak powers of 44 MW and 21 MW at 1-GHz and 2-GHz, respectively, with a 0.11–0.3 T axial magnetic field.

RF pulse shortening is a long-standing issue in high power microwave (HPM) devices. Several causes have been observed or proposed over the years, including cathode and anode plasma expansion, multipactor RF window breakdown, poor RF contacts, and generator impedance mismatch. In our recirculating planar magnetron (RPM) experiments at the University of Michigan [1], we routinely encounter this phenomenon, and have previously attributed it to expanding cathode plasma, which modifies the synchronism condition and disrupts magnetron operation. Using an ultra-fast intensified 12-frame camera, we have now imaged the plasma formation and evolution within the magnetron. These images provide insight into the probable sources of pulse shortening in the RPM.

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.

Additive manufacturing techniques, like 3D printing, offer many benefits to the design and manufacture of high power microwave (HPM) components, including the ability to conduct rapid prototyping. A good prototype, however, must be a suitable approximation of the production device. To that end, we have evaluated metallized 3D printed plastic anodes for use in a recirculating planar magnetron [1]. While other authors have examined a metallized plastic structure in an HPM device [2], our work is the first use of a 3D printed structure, and the first where the electron beam impacts the 3D printed anode.

A software-hardware complex intended for investigating spatial distributions of the plasma spectral emissivity is described. It allows us to record and identify the lines and systems of molecular bands in an automatic mode and to perform computer processing of spectra. Molecular bands of deuterium for different electronic-vibrational-rotational transitions are identified. The excitation temperatures of atomic levels, translational, rotational and vibrational temperatures are estimated for a discharge in a planar magnetron.

The mechanical properties of ultra-fine-grained (UFG) 150 μm silver interlayers prepared by planar magnetron sputtering were studied using microshear torsion tests. The interlayers have very high ductility in pure shear, comparable to conventional grain sizes, and show a mechanical steady-state. The Hall–Petch behavior at 1.25 μm is consistent with other earlier work. The hardening rates (dσ/de) are substantially higher in the UFG Ag. The saturation stress and strain-rate sensitivity at this stress are identical to coarse-grained silver.

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.

Thin ZnO–SnO 2 films were deposited on glass substrates by opposed planar magnetron sputtering, in which ZnO and SnO 2 :Sb (Sb 2 O 5 3 wt% doped) targets face each other. Glass substrate temperatures ( T s ) were held at 150°C and 250°C. As an experimental parameter, current ratio δ , ZnO target current divided by the sum of ZnO and SnO 2 target currents, was used. Compositions of as-deposited film were changed with the current ratio δ . Amorphous transparent films appeared over the range of 0.47⩽ δ ⩽0.80 (Zn/(Zn+Sn)=0.28–0.76) at T s =150°C, over the range of 0.33⩽ δ ⩽0.73 (Zn/(Zn+Sn)=0.32–0.66) at T s =250°C. Crystalline ZnSnO 3 and crystalline Zn 2 SnO 4 was not obtained in any of the as-deposited films, even at δ =0.62 (Zn/(Zn+Sn)=1/2) or δ =0.73 (Zn/(Zn+Sn)=2/3). Amorphous films exist as form of (ZnSnO 3 ) 1− x (SnO 2 ) x over the range of 0.50⩽ δ ⩽0.62 (0⩽ x ⩽0.5) and (ZnSnO 3 ) 1− y (ZnO) y over the range of 0.62⩽ δ ⩽0.73 (0⩽ y ⩽0.5). The minimum resistivity of the deposited amorphous films was 3.6 ×10 −2 Ω cm at δ =0.50 (Zn/(Zn+Sn) =0.33), T s =250°C.