Thermal evaporation allows thin layers of metals such as copper, silver or gold, or other materials such as silicon dioxide or indium tin oxide to be deposited on substrates. This method can also be used to coat substrates with organic semiconductors. Thermal evaporation is also utilized in the production of CIGS solar cells (co-evaporation of copper, indium, gallium and selenium) as well as in the production of organic solar cells (evaporation of monomers). FHR is one of the leading suppliers of systems in this field.
Thermal evaporation, like sputter deposition, is a PVD (physical vapour deposition) thin film technology. The coating material is heated until it evaporates (liquid) or sublimates (solid). The resulting vapour then condenses on the surface of the substrate and forms the final coating.
Thermal evaporation is also a high vacuum process similar to most other PVD processes. Reactive thermal evaporation is also possible; for example, deposition of indium tin oxide can be improved by admitting ionised oxygen into the vacuum chamber.
In comparison with other PVD thin film processes, thermal evaporation allows for particularly high coating rates, depending on the evaporation material and the desired coating properties. To guarantee the optimal process parameters for evaporation, FHR can offer tools with different evaporation sources such as crucible or boat, linear or jet as well as special evaporators.