An etching system includes: a vacuum chamber; a stage for mounting a workpiece, the stage being disposed within the vacuum chamber; a first electrode located within the vacuum chamber and above the stage; a second located between the first electrode and a ceiling of the vacuum chamber; a gas supply for introducing a process gas into the vacuum chamber; a variable capacitance element connected to the second electrode; and a radio frequency power supply connected to the first electrode and connected through the variable capacitance element to the second electrode. The radio frequency power supply supplies radio frequency power to the first and second electrodes to produce an inductively coupled plasma in the process gas within the vacuum chamber.