The thickness x, of tungsten fuzz layers are measured for non-varying helium (He) plasma exposure conditions spanning four orders ion fluence (1024–1028m−2) and flux (1019–1023 m−2 s−1), at 1000–1140 K under low energy He impact (50–80) eV. data obtained complemented by previously published similar growth conditions, collectively analysed. new analysis allows the reconciliation fast high with commonly observed slower lower flux. It is demonstrated that standing t1/2 time dependence a special...

Plasma jet arrays are considered a viable means to enhance the scale of downstream surface treatment beyond that possible using single plasma jet. Of paramount importance in many processing applications is uniformity exposure on substrate, which can be compromised when multiple jets arranged close proximity due their interaction. This contribution explores dielectric barrier array consisting individually ballasted jets. It shown capacitive ballasting promising technique allow simultaneous...

An electron-emitting probe has been used to measure the temporal evolution of plasma potential Vp along a line from target (Ti) substrate above racetrack in high-power impulse magnetron sputtering discharge pulsed at 100 Hz. The 20 ns time-resolution allowed us observe highly dynamic nature as voltage waveform develops, with large negative values (−210 V) and strong gradients existing magnetic trap region first 6 8 µs. After 55 60 µs, is elevated towards ground (0 bulk electric field...

We demonstrate the utility of a ?tissue model? to monitor delivery plasma jet-generated reactive oxygen species (ROS). report on helium jet interactions both across surface and into subsurface (defined as 150??m 1.5?mm) tissue model. The model comprises gelatin gel encapsulating homogeneously dispersed chemical or biological reporter molecule. Jet?surface result in (i) star shaped patterns that resemble those previously reported for surface-plasma streamers insulators (as imaged by Pockels...

Plasma polymerisation is a technologically important surface engineering process capable of depositing ultra-thin functionalised films for variety purposes. It has many advantages over other processes, including that it completely dry, can be used complex geometries, and the physico-chemical properties film tailored through judicious choice processing conditions. Despite this, mechanisms growth are largely unknown, current models based on purely chemical arguments. Consideration some basic...

Using an energy-resolved mass spectrometer and a time-resolved Langmuir probe, the distribution of bombarding ion energies, their fluxes energy at substrate in asymmetric bi-polar pulsed DC magnetron have been determined. The discharge was operated Ar pressure 0.53 Pa with Ti target frequencies 100 350 kHz range duty cycles (from 50 to 96%). At kHz, Ar+and Ti+ time-averaged functions (IEDFs) reveal three peaks, which are low (<10 eV), mid-range (20-50 eV) high (60-100 eV). We correlate these...

Using an emissive probe the distribution of plasma potential Vp in bulk a dc Magnetron discharge has been determined for range argon pressures (0.26, 0.53 and 0.78 Pa) cathode voltages (between -236 -338 V). The results reveal large axial variation space confined plasma, with ΔVp~25 V over distance 5 cm, from to sheath-edge. By combining derived electric field modelled magnetic field, single-particle drifts have found, namely electron E∧B, ∇B curvature drift speeds. predicted E∧B speeds...

Using a time-resolved Langmuir probe the temporal evolution of bulk plasma parameters in high-power impulse magnetron sputtering (HiPIMS) discharge was investigated for number different conditions. The operated argon between 0.5 and 1.6 Pa with titanium target peak power densities up to 1000 W cm−2. pulse width repetition rate were held constant at 100 µs Hz, respectively. an OML analysis as well Druyvesteyn formulation, electron densities, effective temperatures energy distribution...

This paper reports on the correlation between gas flow and plasma behaviour in outflow of a micro-atmospheric pressure jet operating helium using both 2D optical imaging Schlieren photography. photography shows that changes from laminar to turbulent conditions after distances 20 50 mm nozzle. Above rate 1.4 slm, length region decreases with increasing rate. However, by contrast visible plume increases until its extension just exceeds region. At this point, becomes decreases. Exposing...

Using molecular beam mass spectroscopy, time-resolved measurements of the ionic species in plasma plume an atmospheric-pressure helium microplasma jet are made for a range excitation frequencies (5, 10 and 25 kHz) source–instrument orifice distances (1, 7 11 mm). Ionic can only be observed visible plume, with main positive being (65.26%) (21.11%), few percentages N + , O NO He . For negative ions, majority (22.68%), (H 2 O) (10.49%) large minority observed, namely clusters, (CO 3 ) The flux...

The time-dependent plasma discharge ionization region model (IRM) has been under continuous development during the past decade and used in several studies of high-power imp ...

This paper reviews the contribution made to observation and understanding of basic physical processes occurring in an important type magnetized low-pressure plasma discharge, pulsed magnetron.

Bioelectric impedance analyses (BIA) provides a valid and reliable measure of body composition in field, clinical, research settings if standard protocol procedures are followed, population-specific equations available utilized. The objective this study was to create cross-validate new BIA equation with representative healthy weight (HW), overweight (OW), obese (OB) young children. Participants were 436 children who 5-11 years age. Dual-energy absorptiometry fat-free mass (FFM) used as the...

Atmospheric pressure plasma jets offer a unique route to transport reactive chemical species generated under highly non-equilibrium conditions remote downstream sample; as such, they have become the device of choice in many biological and materials processing applications. This contribution explores techniques manipulate propagation dynamics fast moving ionization front dielectric barrier jet, after it is launched from powered electrode. To achieve this, electric field region through which...

Ambient molecular beam mass spectrometry (MBMS) has been used to study how different capillary widths (530 µm and 2.4 mm) excitation waveforms (continuous wave kHz pulsed dc) affect the ionic composition of atmospheric pressure plasma jets. It is shown from time-averaged ion intensities that reducing width jet results in a significant increase variety both positive negative ions detected within discharge. We discuss this terms changes flow velocity onset turbulence plume. Changing mode had...

The marked difference in behaviour between HiPIMS and conventional DC or pulsed-DC magnetron sputtering discharges with changing magnetic field strengths is demonstrated through measurements of deposition rate.To provide a comparison techniques the same circular was operated three excitation modes at fixed average power 680 W pressure 0.54 Pa nonreactive titanium.The total strength B cathode surface middle racetrack varied from 195 to 380 G. show expected that rates fall decreasing (here by...

The propagation dynamics of an atmospheric-pressure plasma jet resemble that a cathode-directed streamer and are determined, in part, by the high localized electric field at head. This contribution employs optical spectroscopy technique based on polarization-dependent Stark splitting shifting visible helium lines to non-invasively measure head field. It is demonstrated comprised high-field region with peak magnitude ∼24 kV cm−1, which followed low-field region, ∼9 identified as tail....