  The importance of accounting for an ambipolar electrostatic potential or a
non-uniform density profile for modelling of inductively coupled discharges is
demonstrated. A drastic enhancement is observed of the power transfer into
plasma for low-collisional, low-pressure, non-local discharges with non-uniform
electron density profiles under the condition of bounce resonance. This
enhanced plasma heating is attributed to the increase of the number of resonant
electrons, for which the bounce frequency inside the potential well is equal to
the rf field frequency.
