SELF-CONSISTENT FLUID MODELING OF RADIO-FREQUENCY DISCHARGES IN 2 DIMENSIONS

Results from a two-dimensional (2D) fluid simulation of a parallel pla te, capacitively coupled radio frequency discharge bounded by a cylind rical insulator with a grounded exterior surface are presented. We fin d that the radial sheath at the insulator focuses current into the pla sma region adjacent to the sheath. This 2D effect has important ramifi cations for the ionization rate, which peaks sharply in the metal-insu lator corners. We have experimentally observed the enhancement of the emission rate in a comer using spatially resolved optical emission spe ctroscopy. A ''thick'' insulator yields radial profiles for the time-a veraged plasma density and potential that are essentially uniform. A ' 'thin'' insulator, however, results in an off-axis maximum in the plas ma density and potential due to the comer ionization.