The thermal radiation effect of substrate on nano-microsized particles levitating in low-pressure reactive plasmas

Abstract

The effect of thermal radiation from the substrate was theoretically investigated on the temperature of a nano-microsized particle levitating in a sheath of low-pressure reactive plasma. The fundamental equation for time variation of the particle temperature was given including the gain and loss terms in heat via the thermal radiation and the heat transfer through the particle–gas molecule collisions. Numerical integration of the equation led to the following results. The particle temperature increases linearly with time at first and then gradually approaches a maximum value. The maximum temperature depends on the substrate temperature and the material properties as well. Applying our result to the case of carbon particles observed in methane plasma, we propose that the particle temperature was about 2000K for the substrate temperature of 1100K and that the particle was in a viscoelastic phase of carbon onion aggregate.