Reactive Ion Etching (RIE) is a method that combines both chemical and physical etching to allow isotropic and anisotropic material removal. The etching process is carried out in a chemically reactive plasma containing positively and negatively charged ions generated from gases that are pumped into the reaction chamber. A mask on top of the substrate is used to protect designated areas from etching, exposing only the areas to be etched. Dry etching offers excellent process control for cleanliness, homogeneity, etch-rate, etch-profile, selectivity and run-to-run consistency, which is critical for high-fidelity pattern-transfer in micro- and nano-system technologies. RIE is extensively used in the field of displays & lighting (LEDs), semiconductors, electronics, MEMS, communication technology, microfluidics, optoelectronics and photovoltaics.