Ion Beam Assisted Deposition
EBPVD systems are equipped with ion sources. These ion sources are used for substrate etching and cleaning, sputtering the target and controlling the microstructure of the substrate. The ion beams bombard the surface and alter the microstructure of the film. When the deposition reaction takes place on the hot substrate surface, the films can develop an internal tensile stress due to the mismatch in the coefficient of thermal expansion between the substrate and the film. High energy ions can be used to bombard these ceramic thermal barrier coatings and change the tensile stress into compressive stress. Ion bombardment also increases the density of the film, changes the grain size and modifies amorphous films to polycrystalline films. Low energy ions are used for the surfaces of semiconductor films.
Read more about this topic: Electron Beam Physical Vapor Deposition
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