tyhjiöhöyrystys

Tyhjiöhöyrystys, known in English as vacuum evaporation, is a physical process used to deposit thin films of material onto a substrate. This technique involves heating a source material under a high vacuum until it vaporizes. The vapor then travels through the vacuum chamber and condenses onto the cooler surface of the substrate, forming a thin, solid layer.

The vacuum environment is crucial for several reasons. It prevents the source material from reacting with air molecules during vaporization, which could contaminate the film or alter its properties. It also allows the vaporized material to travel unimpeded to the substrate, ensuring uniform deposition.

Various methods can be employed for vacuum evaporation. Thermal evaporation uses a resistive heater to heat the source material, while electron beam evaporation uses a focused beam of electrons to achieve higher temperatures and vaporize refractory materials. Sputter deposition, though related, involves bombarding a target material with ions to eject atoms, which then deposit onto the substrate.

Vacuum evaporation is a versatile technique used in numerous applications. It is widely employed in the manufacturing of optical coatings for lenses and mirrors, reflective layers for displays, protective coatings for electronic components, and decorative finishes for various products. The ability to control film thickness and composition makes it a valuable tool in scientific research and industrial production.