Computer simulation of inductively coupled plasmas using chlorine feed gas

An inductively coupled plasma (ICP) operated at low pressure has been modeled. In order to save computation time, a global (zero-spatial dimension), steady state model (similar to that used by Lee et al. (1)) incorporating mass balances for ionic and neutral chemical species and energy balances for the electrons is used to determine species densities and electron energy. At low pressure (1 mTorr), the net dissociation of C-2 to Cl is quite high (up to 93%), with the final Cl-2 concentration depending on the recombination of Cl back to Cl-2. When the reactor height and radius are increased, the diffusion losses to the walls decrease; therefore less ionization is needed which occurs at lower electron energy. Even fairly large changes (a factor of 3) in the height and radius give relative small changes (less than 40%) in the total ion density and electron density.