PULSED SHEATH DYNAMICS IN A SMALL CYLINDRICAL BORE WITH AN AUXILIARY ELECTRODE FOR PLASMA IMMERSION ION-IMPLANTATION

The temporal evolution of the plasma sheath in a small cylindrical bor e with an auxiliary electrode is calculated for zero-rise-time voltage pulses. The ion density, flux, dose, ion energy distribution, and ele ctric field are determined by solving Poisson's equation and the equat ions of ion motion and continuity using finite difference methods. Our results indicate that the implantation time is about halved and sligh tly more than 50% of the ions possess impact energy higher than the ma ximum achieved when an auxiliary electrode is absent. The resulting io n flux, ion current, as well as ion energy distribution, are also dete rmined. (C) 1997 American Institute of Physics.