The plasma sheath around planar probes: effects of ion collisions

The 2D numerical model of the ion current collection by a planar probe has been developed on the basis of a particle in cell with the Monte Carlo collision method for ion motion. This model is used to reveal the effects of ion collisions on the probe sheath area and spatial distribution of plasma density and to warn against current-voltage probe characteristic misinterpretation at plasma density measurements by commonly used Langmuir probe methods.