Dust on a surface in a plasma: A charge simulation

An electrically isolated particle on a substrate surface will be electrically charged when a plasma is applied above it. We show that the magnitude of this charge is determined by a balance of the impeding ion and electron fluxes that are strongly influenced by the nearby substrate. By simulating this process, we find that the charge density of the particle can be much higher than that of the substrate. This is due to the height of the particle, which causes additional electron collection.