MODEL RELEASED. Plasma etching. Technician in clean room clothing controlling the plasma etching of a semiconductor wafer using a computer. The wafer is placed in the vacuum chamber inside the plasma etcher (silver). A gas, such as bromine, is then pumped into the chamber and a voltage applied to create a plasma (charged gas). The ions of the plasma etch the wafer, to form microchips for example. Photographed at Newcastle University, UK.