December 11, 2017
General Information
1. on plating utilizes concurrent or periodic energetic particle bombardment of the depositing film to modify and control the composition and properties of the depositing film.
2. The depositing material may be vaporized either by evaporation, sputtering, arc vaporization, or other vaporization source.
3. The energetic particles used for bombardment are usually ions of an inert or reactive gas, or ions of the depositing material ( film ions).
4. Ion plating can be done in a plasma environment where ions for bombardment are extracted from the plasma
Advantages of Ion Plating
1. Significant energy is introduced into the surface of the depositing film by the energetic particle bombardment.
2. Surface coverage can be improved over vacuum evaporation and sputter deposition due to gas scattering and “ sputtering re-deposition” effects.
3. Controlled bombardment can be used to modify film properties such as adhesion, density, residual film stress, optical properties.
4. Film properties are less dependent on the “angle-of-incidence” of the flux of depositing material than with sputter deposition and vacuum evaporation due to gas scattering, “sputtering/re-deposition” , and “atomic peening” effects.
5. Bombardment can be used to improve the chemical composition of the film material by “ bombardment-enhanced chemical reactions” and sputtering of un-reacted species from the growing surface.
6. In some applications the plasma can be used to “ activate” reactive species and create new chemical species that are more readily absorbed so as to aid in the reactive deposition process ( reactive ion plating )
Disadvantages of Ion Plating
1. There are many processing variables to control.
2. It is often difficult to obtain uniform ion bombardment over the substrate surface, leading to film-property variations over the surface.
3. Substrate heating can be excessive.
4. Under some conditions the bombarding gas may be incorporated into the growing film.
5. Under some conditions excessive residual compressive film stress may be generated by the bombardment.
6. Ion plating is used to deposit hard coatings of compound materials, adherent metal coatings, optical coatings with high densities, and conformal coatings on complex surfaces.
7. Droplets which might affects the coating surface.
