Effect of ion bombardment on the structure and properties of polycrystalline chromium films

Polycrystalline chromium films were fabricated by electron beam evaporation with concurrent bombardment using argon ions from an ion gun or by sputtering with substrate bias. The microstructure and composition of the films were characterized using TEM/EDS. It was found that the grain size/shape, porosity, and argon content of the films strongly depend on the deposition parameters such as bombardment ion current density, deposition rate, argon pressure and substrate bias. Film properties including residual stress, resistivity, and reflectance were measured. A correlation of deposition, structure, and properties is discussed.