Selecting the correct thermal evaporation source can sometimes prove difficult. There are several factors that will need to be considered when doing so.
Length of the Source
The first thing that is needed is the length between the electrodes. This will dictate how long of a source is needed. In some cases, adaptors can be used in order to use shorter sources.
Material to be Evaporated
The material plays a key role in selecting the appropriate evaporation source. The VP curve of that material should be reviewed to determine the temperature range that the material will need to be in order to have a desirable deposition rate. Each material behaves differently, especially in a molten state. Review the material deposition table and also the evaporation materials pages for information by material as well as recommendations on appropriate evaporations sources.
Once the required temperatures are known, available power should be reviewed. Each source will have different power requirements to hit given temperatures. This may limit the amount of sources that exist for the temperature range required. When narrowing down the source, review the power vs temperature information listed in the ordering table.
Thickness of Films
Capacity of sources will vary based on the shape of the source. For thicker films, crucibles may be a better option, assuming enough power is available to heat them. For thinner films, standard boats could be a better option. To determine how much material will be needed to run a desired film, see our Material Needed to Deposit 1 Micron Film Calculator.
For more information or assistance in selecting the best source for your application, please email firstname.lastname@example.org.