PECVD uses electrical energy to generate a glow discharge (plasma) in which the energy is transferred into a gas mixture. This transforms the gas mixture into reactive radicals, ions, neutral atoms and molecules, and other highly excited species. These atomic and molecular fragments interact with a substrate and, depending on the nature of these interactions, either etching or deposition processes occur at the substrate. Since the formation of the reactive and energetic species in the gas phase occurs by collision in the gas phase, the substrate can be maintained at a low temperature. Hence, film formation can occur on substrates at a lower temperature than is possible in the conventional CVD process, which is a major advantage of PECVD.
Excellent coating homogeneity is guaranteed by the linear microwave sources. Typical coatings are SiNx, SiOx, and Al2O3 layers used as optical or protective coatings.
Applications are found in thin film encapsulation of sensitive thin and flexible electronics like OLEDs, thin film batteries, Perovskite cells, Quantum Dot devices and printed electronics.