The Inductively Coupled Plasma system (tool #54) is an Oxford Plasmalab 100/180 model with vacuum load-lock that accommodates up to 8'' diameter wafers. Chlorine-based gases are used for etching semiconductors and some metals and Flourine-based gases provide deep Trench Etching capability in Silicon. Typical semiconductor materials that are etched are: AlGaAs, InGaAs, AlGaSb, GaN, and Si. Metals that can be etched include Al, Ti, and thin Pt layers. The 300 watt RF system produces a high-density, low- pressure, low-energy inductively coupled plasma. This type of plasma allows high selectivity and aspect ratio etching for depths greater than 250 microns. The system control is via a standard PC, which automatically loads a wafer into the process chamber. Once in the chamber, the wafer is placed onto a helium-cooled chuck during the process with liquid nitrogen available for thermal stability . The substrate is RF-biased independently of the inductively coupled RF plasma, which results in low ion energies and thus low ion bombardment. Consequently, an ICP system will provide high chemical etch selectivities with high etch rates.