Hypergravity diagnostics and material synthesis in noble gas gliding arc plasma

The behaviour of gliding arc discharge in argon and helium has been studied under normal gravity and hypergravity conditions. The similar influence of increased gas flow and increased gravity is reported. The measured electrical quantities show the differences between glide arc in argon and helium. Material synthesis of carbon nanomaterial has been carried out in mixture of helium with methane in both normal gravity and hypergravity

Particle contamination control by application of plasma

With the introduction of Extreme Ultraviolet (EUV) lithography, the control of contamination has become crucial. Sources for contamination in EUV lithography scanners are not limited to only particle generation and release inside the scanner environment but may be introduced from outside as well, e.g. through translational and/or rotational (robotic) feedthroughs. In this contribution we highlight our joint (TU/e and VDL ETG) research efforts aimed at the development of plasma-enabled contamination control strategies. The focus in this research is on airborne particles immersed in a low pressure gas flow that interact with both the afterglow of a plasma and an externally applied electric field. A flexible experimental setup has been developed and will be introduced which is able to study the interaction between contaminants, plasmas and externally applied electric fields. Our results show that the designed configuration allows to carefully control the residual charges of the particles as well as their positions and trajectories with respect to the gas flow in which they are immersed. These results, together with the understanding of the underlying principle processes, open-up various possibilities to achieve improved cleanliness of the mentioned systems

Charge control of micro-particles in a shielded plasma afterglow

In this work, charge control of micro-particles from ~ -40 to +10 elementary charges is presented. This is achieved at 0.9 mbar argon in the spatial afterglow of an inductively coupled plasma by solely changing the strength of an externally applied electric field. Crucial in the presented experiments is the use of a grounded mesh grid in the cross section of the setup, separating the active plasma region from the "shielded" spatial afterglow. While in the regions above the mesh grid all particles reached a constant negative equilibrium charge, the actual control achieved in the shielded spatial afterglow can most probably be explained by variations of the local ion density. The achieved charge control not only opens up possibilities to study nano-scale surface charging physics on micro-meter length scales, it also contributes to the further development of plasma-based contamination control for ultra-clean low-pressure systems