Theory of magnetized, coupled, rf-driven plasma sheaths in one dimension

A set of equations for magnetized plasma sheaths in rf capacitance discharg es is developed within the adiabatic electron, fluid ion framework. It diff ers from previous approaches in that (a) ion demagnetization i.e., the deta chment of the ion flow from the magnetic lines caused by electrostatic grad ients, is introduced self-consistently, (b) the ion injection velocity from the presheath is reevaluated to ensure the ion-electron Aux balance, and ( c) two symmetrically opposed coupled sheaths are driven by a sinusoidal dri ving voltage instead of a sinusoidal current. It is found that the sheath p otential and thickness increase considerably with increasing magnetic incli nation theta relative to the electric field compared to the unmagnetized re sults; the latter are recovered at the parallel magnetic field limit. Also, the ion injection velocity along the magnetic lines is subsonic and depend s on the magnetic inclination. Finally, a sinusoidal ac voltage drives an a nharmonic sheath current, while a sinusoidal current drives anharmonic volt age. [S1063-651X(99)09001-7].