Experimental evidence of collisionless power absorption in inductively coupled plasmas

Electromagnetic power absorbed in inductively coupled plasma driven by a planar coil has been found directly from axial distributions of the rf electric field and current density measured with magnetic probes. It is shown that at gas pressure around 1 mTorr the absorbed power is much larger than that found from the cold plasma theory, and is in reasonable agreement with the one calculated in the framework of a theory for the anomalous skin effect in a two-dimensional system accounting for spatial dispersion of plasma conductivity.