What is vacuum evaporation?

Vacuum evaporation (vapor deposition) is a processing technology that involves heating materials in a high-vacuum space until they turn into vapor and form a thin film (coating) on the substrate.

When powerful energy is applied to evaporation materials using an electronic beam or lasers in a vacuum environment, they evaporate and coat a nearby glass or plastic substrate, forming a thin film. This process is called vacuum evaporation, and it is one of the key methods of creating a thin film over objects.

Why is a vacuum environment necessary?

Under atmospheric pressure, there would be many gas molecules present other than those of the vacuum deposition materials. These gas molecules would obstruct the evaporation materials from stably adhering to the substrate.

Therefore, evaporating the evaporation materials under vacuum conditions that are 1 to 100-millionth of atmospheric pressure enables more reliable formation of the thin film on the substrate.