Description
As semiconductor devices continue to shrink, maintaining ultra-clean fabrication environments becomes increasingly critical. To eliminate unwanted particles from low-pressure, high-purity processing systems, a novel technique known as the “plasma seal” has been proposed. This method uses plasma to electrically charge contaminant particles, enabling their removal through an externally applied electric field. However, because the plasma screens the particles from the electric field, effective deflection can only take place either outside the active plasma region, immediately after the plasma is switched off or during the spatiotemporal afterglow, which combines aspects of both regimes.
Recent research has advanced the understanding of particle charging mechanisms in the spatiotemporal afterglow, yet the role of particle clustering remains largely unexplored. In this contribution, we examine how cluster size influences particle charging behavior. Optical emission spectroscopy is employed to link particle charge to key plasma parameters. The findings provide experimental validation of established theoretical models describing particle charging processes.