EFFECT OF ION ENERGY ON THE MECHANICAL-PROPERTIES OF ION-BEAM-ASSISTED DEPOSITION (IBAD) WEAR-RESISTANT COATINGS

Ion beam assisted physical vapor deposition offers a number of advanta ges over other surface modification methods with respect to the proper ties of wear resistant coatings. These properties include density, adh esion to the substrate, crystallographic orientation, durability and r esistance to degradation by moisture. These improved film properties d erive from the physical and chemical processes associated with the imp ingement of energetic ions onto the surface of a growing film. Such pr ocesses include sputtering and desorption of atoms from the substrate, implantation of atoms into the substrate, chemical reactions at the s urface, cluster nucleation and dissociation, enhancement of surface di ffusion, atomic displacements in the bulk, as well as energy and momen tum transfer to the atoms in the growing film. A review of models for the influence of ion energy and momentum transfer to a growing film su ggests that the effects of ion bombardment may be categorized accordin g to the ion energy.