Plasma structures in an electron cyclotron resonance plasma processing device

Plasma parameters are measured in a low-pressure discharge plasma produced by the 2.45-GHz electron cyclotron resonance. Radial plasma profiles, which are important for homogeneous plasma processings, are found to be very sensitive to the resonance position in a plasma production chamber. Quite inhomogeneous plasmas are obtained when the resonance position is set in the narrow production chamber (cavity) while uniform plasmas are produced when the resonance position is in a wide space chamber following the production chamber. Plasma potentials determining the ion flow speed toward the substrate decrease gradually along the diverging magnetic field lines up to the ion sheath region in front of the substrate. The plasma structures observed are well consistent with theoretical results.