Evaporation is the method where source materials are heated to high temperatures where they melt and then evaporate or sublimate into a vapor. These atoms then precipitate into solid form onto surfaces, coating everything in the chamber, within line of sight, with a thin layer of the source material. Typically this deposition is done in a high vacuum chamber to minimize gas collisions of the source material on its way to the substrate and to reduce unwanted reactions, trapped gas layers and heat transfer.
The atoms in the vapor from evaporation have only thermal energy and strike the substrate with little or no kinetic energy and heat transfer from the hot sources to the sample is dominated by light radiation. The evaporators in the LNF are dome/liftoff tools with long throw distances with cold walled chambers and small/centered point sources.
This means that, with the directionality of the evaporation, the material will strike the substrate as a normal angle and, with low heat transfer, the substrates do not get very hot as the films is depositted. This makes them ideal for liftoff applications, depositions where the substrates cannot handle any plasma heating and thicker films. They are poorly suited for any application requiring sidewall coverage or controlled stress or stoichiometry.