Abstract: An improved plasma reactor apparatus and method are disclosed. Improved uniformity of etching and etch rate are achieved in a reactor through the use of electrodes powered at high and low frequencies. In one embodiment of the invention the workpiece which is to be etched rests on an electrode powered at a low AC frequency of about 100 KHz. A second electrode is powered at a high AC frequency of about 13.56 MHz. A third electrode is maintained at ground potential. High and low frequency AC fields acting on a reactant material optimize the dissociation of the reactant material and the ion energy of the plasma generated reactant species.