Preparation, structure and properties of TaN and TaC films obtained by ion beam assisted deposition

Tantalum nitride and tantalum carbide films were prepared by the method of ion beam assisted deposition (IBAD). The results of transmission electron microscopy (TEM) and X-ray diffraction showed that the films are all fee structures and the grain sizes in the films are very small(about 10 to 20 nm). The composition depth profile and chemical binding character of films were determined by Auger electron spectroscopy (AES) and X-ray photo-electron spectroscopy (XPS). Measurements of film properties, such as microhardness, adhesion of film to substrate, and surface resistance, were made on a microhardness tester, a scratch tester and a bridge of resistance measurement with four-pole probe, respectively. The residual stress, dislocation density and dislocation distribution in the films were calculated by a method called X-ray diffraction line profile analysis developed by Wilkens and Wang et al. According to the elastic theory of dislocations, the microhardness of films was also calculated by using the parameters of dislocations obtained.