The Uniaxis Inductively coupled Plasma 790 system is used to etch various materials, such as silicon dioxide, silicon nitride, and various polymers from the surface of a substrate using several reactive gases in a RF induced plasma. This single wafer system consists of a top coil and a bottom electrode for application of RF fields while the bottom plate can helium cooled. The system can accepted wafer sizes up to 6 inches. A 2 MHz RF at 1000 watt max can be applied to the top coil while the bottom electrode is supplied with 13.56 MHz RF at 500 Watts max. The process often has high selectivity to the etched material and anisotropic etching can be achieved. Oxygen, Argon, Sulfur hexafluoride and Trifluoromethane are used as etching gases. A mass flow controller sets the flow rate for each gas and the pressure is controlled separately by a butterfly valve between the chamber and the pump, so pressure as small as 2mT can be achieved in the chamber for higher etch rate.