PVD – THERMAL EVAPORATION
It’s still the most widespread system in the metallization field due to its easy use and the effectiveness of deposition in the presence of substrates with complicated shapes and structures.
The deposition source consists in tungsten filaments, which are usually put in the central part of the process chamber, over them is put the piece of metal that you want to deposit.
The substrates are located around the filaments and they are made to rotate (rotation and translation) during metal deposition phase.
In order to obtain the metal deposition inside the process chamber it’s necessary to reach a vacuum value generally not superior than 4×10-4 mbar (high vacuum). When it’s reached the necessary vacuum value starts the evaporation phase that consists in tungsten filaments heating: when they get incandescent, they fuse the metal that evaporates and condenses on the substrates surface.
ARZUFFI’s equipments are provided with a high quality evaporation phase thanks to a control system called “Feedback” because exerts a retroactive control of the process (Profibus link with data transfer in milliseconds) in order to have a gradual and constant improve of the power on the filaments, both in preheating and heating phase, in this way it’s possible to avoid sudden changes in power that would cause deposition defects (sprinkles, drops, etc.).
Example of evaporation controlled by “feedback”
Pre-heating Heating Evaporation
PVD – SPUTTERING
It’s a metal deposition system originally used only on substrates with level surfaces, instead now it’s applied also on tridimensional pieces but with easy shapes and structures.
The deposition source is a magnetic cathode with a metallic plate (target made of the material that it’s required to deposit) installed on it.
The magnetic cathode is generally located on one side of the process chamber. The substrates rotate in front of the source. When is reached the required vacuum value it’s set a high voltage and it’s injected Argon gas.
The Argon positive ions are undergone to an acceleration process on the negative cathode and due to that they expel the atoms from the metallic plate. Then these atoms condensate on the substrates.
Functioning pattern of Sputtering process
The magnetic cathode, as a deposition source, can has various shapes: circular, cylindrical, rectangular. Depending on the application demands is planned the best solution in terms of quality and productivity.