DCglowdischarge

DC glow discharge is a type of electrical plasma created by passing a direct current through a low-pressure gas. When the voltage between two electrodes in a gas exceeds a certain breakdown potential, the gas ionizes, becoming conductive and forming a plasma. This plasma emits light, giving rise to the term "glow discharge." The discharge typically appears as a luminous region with distinct zones, including the cathode glow, negative glow, Faraday dark space, positive column, and anode glow. The characteristics of the glow discharge, such as its color, intensity, and structure, depend on the gas used, its pressure, and the applied current and voltage. DC glow discharges are used in a variety of applications, including fluorescent lighting, sputtering for thin-film deposition, plasma etching, and surface treatment. The process involves a complex interplay of electron-impact ionization, excitation, recombination, and diffusion within the gas. Maintaining a stable DC glow discharge requires careful control of the gas pressure and current density.