Effect of variation of presheathions temperature on multicomponent magnertized plasma-wall transition

Abstract

The characteristics of the magnetized plasma sheath have been studied using the kinetic trajectory simulation method for different ion temperatures of two positive ions. Kinetic equations are solved for a given initial boundary condition to study the effects on electric potential, particle density, electric field, and space charge density of the flow of particle species towards the wall. The electric potential is steeply increasing towards the wall for all the cases and reaches the wall quickly for higher heavier ions’ temperatures and slower for equal ions’ temperatures. From the sheath entrance, the number density of all particle species decreased, ion density remained maximum for their respective higher ion temperatures, and electron density decreased much faster than positive ions and reached a minimum in all cases. The gap between the value of the electric field in the injection boundary and in the wall is maximum for equal ion temperature of both ions and decreases the difference on increasing any of the two ions’ temperatures. This is because a magnetic field dominates near the sheath entrance and an electric field dominates close to the wall. The space charge density is zero at the sheath entrance and it goes on increasing towards the wall to attend its maximum value due to the rapid decrease in electron density. This work gives a brief description of sheath characteristics near the wall, which are useful for multiple plasma applications such as material processing, surface modifications, etching, etc.