Michael Faraday, born in 1791, was an English scientist who undertook fundamental electrotechnical research, for example of electrolysis. The physical unit for the electrical capacitance [F] = [Farad] is named after him. This unit is also used to specify the capacity of capacitors. The Faraday cage is likewise named after Michael Faraday.
A Faraday cage is a metal housing. Electromagnetic fields in the interior of the Faraday cage do not pass through to the outside, and vice versa; accordingly, it is used for electromagnetic shielding. For some plasma processes, a potential-free plasma is required, or it is necessary to prevent the action of ions and electrons , for example to keep the substrate for getting charged. To implement this, the substrate is put in the Faraday cage in which excited atoms and radicals are active but no ions.