Two types of evaporators
“The evaporation is done with evaporators that are found in the preparation chamber of EMIL, which can be of two types: a conventional (resistive heated) evaporator – used to evaporate inorganic precursors and an beam evaporator – used to evaporate metals. Both of these evaporators are present and used at EMIL – says Núria. Depending on the substrate, the evaporating material and the desired final properties, Núria uses both evaporators, but she has a soft spot for the beam evaporator which, I must also admit, sounds really cool!
The conventional evaporator is composed of a crucible – where the precursor is placed – and a resistive heating coil that heats up the material up to its sublimation temperature. The e-beam evaporator, on the other hand, uses an electron beam source that heats up the material when it is directed on it. One important advantage of the e-beam evaporator is the fact that it is able to reach higher temperatures allowing also the deposition of materials with high sublimation temperatures, as e.g. metals. The working principle of both evaporators can be seen on the figure below, which is provided by the courtesy of Núria and it is an extract from part of her Master thesis writing.