Unbalanced magnetic field configuration: plasma and film properties

Abstract

Coatings of CrN, TiN, ZrN, TaN and NbN were deposited using an unbalanced magnetronsputtering system with two different degrees of unbalancing to investigate the effect of thedegree of unbalancing on both plasma characteristics and film properties. The degree ofunbalancing was determined by an extensive characterization of the magnetic field fluxes in theX–Z plane perpendicular to the target. Then, the plasma parameters, such as electrontemperature, plasma potential, plasma density and ion current density, were obtained foreach target and as a function of the unbalance coefficient. The film microstructure,hardness, corrosion and wear resistant were measured to determine the effect of the degreeof unbalancing on these properties. The results suggested that the degree of unbalancing,through the variations induced in the ion bombardment and plasma ionization, had astrong influence on the film hardness, microstructure and preferred orientation.