The transparent, yellowish film that covers the surface of the melt is aluminum carbide and there is risk of this contamination in films. It is the result of applying high beam power during e-beam evaporation which causes increased thermal load on the crucible. Carbon from the liner then infiltrates the aluminum melt. When this occurs, the evaporation rate will plummet. The natural reaction is to increase the power. However, this only exacerbates the problem. Applying lower beam powers from the beginning of the process will help to minimize this threat.
Category: Deposition Materials
Sub-Category: Evaporation Pellets, Pieces and Wire