The Double Sheath at the Plasma‐Wall Boundary

摘要: The relation between plasma parameters determining a steady-state charged sheath at plasma-wall boundary was derived and analyzed using fluid model, which accounted for inertia partial pressure of both components. generalizes the well-known Bohm criterion and, in particular, shows that steadystate may be formed some cases where is not satisfied. Conditions allowing formation double structure were formulated analyzed. It shown only if a) generalized satisfied, b) Sagdeev potential has minimum. consists two sub-sheath different polarity, depends on wall polarity component temperatures inertia. For positive potential, adjacent to (the edge) enriched by negative particles, while polarities are reversed potential. An analytical theory illustrated numerical solutions Poisson equation special cases. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)