Low-pressure plasmas offer a unique possibility of confinement, control, and fine tailoring of particle properties. Hence, dusty plasmas have grown into a vast field, and new applications of plasma-processed dust particles are emerging.During the deposition of thin amorphous films onto melamine formaldehyde (MF) microparticles in a C2H2 plasma, the generation of nanosized carbon particles was also studied. The size distribution of those particles is quite uniform.In another experiment, the stability of luminophore grains could be improved by coating with protective Al2O3 films that are deposited by a plasma-enhanced chemical vapor deposition (PECVD) process using a metal-organic precursor gas. Coating of SiO2 microparticles with thin metal layers by magnetron sputtering is also described. Especially the interaction of the microsized grains confined in a radio frequency (rf) plasma with the dc magnetron discharge during deposition was investigated. The observations emphasize that the interaction between magnetron plasma and injected microdisperse powder particles can also be used as a diagnostic tool for the characterization of magnetron sputter sources.
Hybrid plasmonic-dielectric materials were fabricated by micro-discharge through water sols of sub-micrometer-sized diamonds mixed with HAuCl 4 acid. Primary characterization of their deposits on a silicon wafer surface by means of electron microscopy and energy-dispersive x-ray spectroscopy indicate close proximity of gold nanoparticles and diamond particles, which is supported by photoluminescence studies demonstrating strong -almost two-fold -damping of diamond luminescence owing to the attachment of gold nanoparticles. UV-near IR spectroscopy of their sols consistently exhibits small red spectral shifts for the fabricated nanomaterials, comparing to bare gold nanoparticles.
Time-resolved measurements have been performed during dual High Power Impulse Magnetron Sputtering (dual-HiPIMS) with two cathodes in a closed magnetic field configuration. The dual-HiPIMS system, operated at a repetition frequency f = 100 Hz and duty cycle of 1\%, was equipped with two different metallic targets (Ti, Cu). Pre-ionization effect of the Ti pulse on the Cu pulse was investigated through argon excited atom density and temperature by means of tunable diode laser absorption spectroscopy. We observed an enhancement of metastable density due to pre-ionization effect. It is shown that the peak density in the Cu pulse increases about 30\% for the case of 15$\mu $s delay then decrease as the delay was prolonged. The effect displays even stronger in the peak density in the afterglow, as well as in the atom temperature behavior. Although metastable atoms are abundantly available in post-discharge, they play minor role in the ignition of the subsequence pulse.
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