Effects of Ti Target Poisoning to Titanium Nitride Coating Fabricated by a Physical Vapor Deposition Technique

摘要

The DC magnetron sputtering is often used for fabricating thin hard coatings for a wide range of industrial applications. The technique allows using DC power for deposition low or non-conductive films from metal target without using expensive RF power for insulation target. However, the performance of DC reactive sputtering is affected significantly by a phenomenon namely target poisoning. When the target poisoning occurs, coating is formed not only on substrate surface but also on target surface, which results in the reduction of deposition rate and coating properties. This paper presents a study on poisoning of Ti target during TiN coating deposition in the Ar + N_(2) atmosphere. Results showed that the target poisoning state is impressed dramatically by partial pressure and flow rate of nitrogen gas. In poisoning mode, the deposition rate was reduced significantly compared to that in the metal mode. In addition, the formed TiN coating exhibited a non-stoichiometric and low adhesion to the substrate.