A method, apparatus and system for initiating a plasma with a low pressure inductively coupled RF plasma to dissociate one or more gases, the method including supplying one or more gases from a source to an inductively coupled plasma discharge chamber; applying RF power to the plasma discharge chamber by capacitive coupling to dissociate the one or more gases and create a plasma; preventing increased contamination from the capacitive electrodes by confining the plasma with at least one constriction acting as an improved power density device; and withdrawing the dissociated one or more gases from the plasma discharge chamber through at least one constriction.