Effect of Ti interlayer on the residual stress and texture development of TiN thin films

The purpose of this study was to investigate the effects of Ti interlayer on the texture and residual stress of overlaying titanium nitride (TiN) thin films. Films were deposited by ion-beam assisted deposition (IBAD) on substrates with or without a Ti interlayer. Residual stresses and pole figures of the grown films were measured by X-ray diffraction (XRD) techniques. Thin films with either in-plane or fiber textures were produced. Results showed that the Ti-interlayer had the effect of changing the in-plane texture. The in-plane texture was switched from the Type 3 texture, where the <100> was along the 45° incident ion beam and the (111) planes were 45° to the film surface, to the Type 1 texture, where the grain orientation rotates 45° along the <100> axis with respect to the Type 3 texture. For a strongly (0002) textured Ti-interlayer, alignment of the (111) plane in TiN was found. For films with fiber texture, the use of a Ti interlayer changed the texture of the TiN film; and a strongly (0002) textured Ti interlayer was necessary to align the texture of the TiN film with the underlayer. The effect of Ti interlayer on the change of TiN texture is most evident for films with loose packing or low residual stress.