Physical vapor deposition (PVD) refers to the use of physical methods to transform solid materials into gases and deposit them on a substrate. Evaporation is one process. The vacuum pump is used to make the chamber reach a vacuum level of 10-3～10-4 Pa, and the material to be vaporized such as metal, oxide or fluoride is heated to melt and gasify. At this time, the atoms of the gaseous film material molecules will fly to the substrate due to the kinetic energy obtained after heating, where they are deposited as solid thin films.
Compared with the sputtering method, it has the advantages of fast plating rate and high material efficiency, which can reduce the cost of the process. In addition, the system design is simple and easy to maintain. It's also easier to monitor the thickness during the process. Multiple evaporation crucibles can be used to continuously grow multi-layer films without breaking the vacuum, so it can be used in industrial mass production occasions.
It has a wide range of applications, including optical films (anti-reflective films for glasses and lenses, etc.), electronic parts (capacitors, semiconductor integrated circuits, etc.), food packaging materials (as a moisture and oxygen barrier extending the shelf life of food).