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Data for the Figures in the publication.The transport of sputtered species from the target of a magnetron plasma to a collecting surface at the circumference of the plasma is analyzed using a particle tracer technique. A small chromium insert at the racetrack position inside a titanium target is used as the source of tracer particles, which are redeposited on the collecting surface. The azimuthal velocity of the ions along the racetrack above the target is determined from the Doppler shift of the optical emission lines of titanium and chromium. The trajectories are reconstructed from an analysis of the transport physics leading to the measured deposition profiles. It is shown that a simple direct-line-of sight re-deposition model can explain the data for low power plasmas (DCMS) and for pulsed high power impulse magnetron plasmas (HiPIMS) by using the Thompson velocity distribution from the sputter process as starting condition. In the case of a HiPIMS plasma, the drag force exerted on the ions and neutrals by the electron Hall current has to be included causing an azimuthal displacement in ⃗ E × ⃗ B direction. Nevertheless, the Thompson sputter distribution remains preserved for 50% of the re- deposited growth flux. The implications for the understanding of transport processes in magnetron plasmas are discussed

This feature article considers the analysis of the initial states of film growth on polymer substrates. The assembled results are based on the cooperation between research groups in the field of plasma physics, chemistry, electric as well as mechanical engineering over the last years, mostly within the frame of the transregional project SFB-TR 87 ("Pulsed high power plasmas for the synthesis of nanostructured functional layers"). This feature article aims at bridging the gap between the understanding of plasma processes in the gas phase and the resulting surface and interface processes of the polymer. The results show that interfacial adhesion and initial film growth can be well controlled and even predicted based on the combination of analytical approaches., Comment: 22 pages, 16 figures

A few years ago, the FAIR data principles were proposed as a guideline for those wishing to enhance the reusability of their data by making them findable (F), accessible (A), interoperable (I) and reusable (R) [Wilkinson et al., Sci. Data 3:160018 (2016)]. Since then, various activities aiming at implementation of the FAIR principles in different fields of plasma science have been started. Within the project QPTDat, INP works together with partner institutions on research data management (RDM) solutions for low-temperature plasma physics. This includes a close collaboration with the CRC 1316 at RUB, where the focus lays on the establishment of data stewards to support RDM in daily practise. The international project Fair4Fusion addresses the RDM needs in the field of fusion plasmas, while PlasmaFAIR at UoY strives to improve the quality and sustainability of plasma research software. This contribution presents current activities at INP, RUB and UoY and emphasizes the need for collaborations and community involvement to derive real benefits from the FAIR principles for research in plasma science., The work was supported by grants 16QK03A (BMBF), EP/V051822/1 (EPSRC), and 327886311 (DFG).

Scaling or smiliarity laws of plasmas are of interest if lab size plasma sources are to be scaled for industrial processes. Ideally, the discharge parameters of the scaled plasmas are predictable and the fundamental physical processes are unaltered. Naturally, there are limitations and ranges of validity. Scaling laws for direct current glow discharges are well known. If a well diagnosed discharge is scaled, the field strength in the positive column, the gas amplification and the normal current density can easily be estimated. For non-stationary high power discharges like high power impulse magnetron sputtering (HiPIMS) plasmas, scaling is not as straight forward. Here, one deals with a non-stationary complex system with strong changes in plasma chemistry and symmetry breaks during the pulses. Because of the huge parameter space no good parameters are available to define these kind of discharges unambiguous at the moment. In this contribution we will discuss the scaling laws for DC glow discharges briefly and present experimental results for a discharge with copper electrodes and helium as plasma forming gas. This discharge was operated in a pressure range from 200 to 1600 hPa with three different electrode diameters (D=2.1, 3.0 and 4.3 mm). Results from breakdown voltage measurements indicate that the pressure and electrode distance cannot be varied independently. Effects of the scaling on the reduced normal current density, the reduced normal electric field in the positive column and discharge temperature will be discussed and limitations highlighted. Compared with these results the added complexity of HiPIMS plasmas will be described. Suggestions in the community how to obtain experimental finger prints of the plasmas will be reviewed and implications from the experiences with DC discharges on the development of similarity laws for HiPIMS plasmas will be discussed., Intended for submission to Journal of Physics D

A beam experiment is presented to study heterogeneous reactions relevant to plasma-surface interactions. Atom and ion beams are focused onto the sample to expose it to quantified beams of oxygen, nitrogen, hydrogen, noble gas ions and metal vapor. The heterogeneous surface processes are monitored in-situ and in real time by means of a quartz crystal microbalance (QCM) and Fourier transform infrared spectroscopy (FTIR). Two examples illustrate the capabilities of the particle beam setup: oxidation and nitriding of aluminum as a model of target poisoning during reactive magnetron sputtering, and plasma treatment of polymers (PET, PP)., 30 pages, 10 figures

Al2O3 thin films have been deposited at substrate temperatures between 500��C to 600��C by reactive magnetron sputtering using an additional arbitrary substrate bias to tailor the energy distribution of the incident ions. The films were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The film structure being amorphous, nanocrystalline, or crystalline was correlated with characteristic ion energy distributions. The evolving crystalline structure is connected with different levels of displacements per atom (dpa) in the growing film as being derived from TRIM simulations. The boundary between the formation of crystalline films and amorphous or nanocrystalline films was at 0.9 dpa for a substrate temperature of 500��C. This threshold shifts to 0.6 dpa for films grown at 550��C.

Microplasma jets are commonly used to treat samples in ambient air atmosphere. The effect of admixing air into the effluent may severely affect the composition of the emerging species. Here, the effluent of a He/O2 microplasma jet has been analyzed in a helium and in an air atmosphere by molecular beam mass spectrometry. First, the composition of the effluent in air has been recorded as a function of the distance to determine how fast air admixes into the effluent. Then, the spatial distribution of atomic oxygen and ozone in the effluent has been recorded in ambient air and compared to measurements in a helium atmosphere. Additionally, a fluid model of the gas flow with reaction kinetics of reactive oxygen species in the effluent has been constructed. In ambient air, the O density declines only slightly faster with the distance compared to a helium atmosphere. On the contrary, the O3 density in ambient air increases significantly faster with the distance compared to a helium atmosphere. This mysterious behavior can have big implication for the use of similar jets in plasma medicine. It is shown that photodissociation of O2 and O3 is not responsible for the observed effect. A reaction scheme involving the reaction of plasma produced highly vibrationally excited O2 with ground state O2 molecules is proposed as a possible explanation of the observed densities. A very good agreement between measured and simulated densities is achieved., Comment: 22 pages, 9 figures, submitted to Plasma Sources Science and Technology