Through the vacuum pump, the cavity can reach a vacuum degree of 10-3~10-4 Pa. The materials to be vaporized, such as metals and acid compounds, are heated until they are vaporized and sublimated, and the gas is attached to the surface of the substrate placed nearby. , Attach to form a thin film.

Evaporation can be roughly divided into physical vapor deposition (PVD) and chemical vapor deposition (CVD). Among them, physical vapor deposition (PVD) is a technology that deposits thin films mainly through a physical process. It has a wide range of applications, almost all materials Substrates can be coated with thin films by physical vapor deposition technology.