Stress Release And Adhesion Stability Of Titanium Nitride Films Deposited By High Power Pulsed Magnetron Sputtering

Titanium nitride(TiN)films fabricated by high-power pulsed magnetron sputtering(HPPMS)have been widely used in the industrial field due to the excellent performance.However,in the practical application of surface modification of TiN film,researchers and producers often find that when the film deposition is just finished,the film modification layer on the surface of the workpiece is integral,and no cracking,delamination and spalling are found.But after a while in natural placement,the film on the surface of the workpiece will show some failure problems,resulting in parts cannot continue to be used.Research shows High residual stress is the main cause of bonding failure of the film prepared by HPPMS.In order to better control the product quality and predict the service life of the film.The films with different compressive stress were prepared by the different substrate bias voltage(-50 V and-150V).The film stress was evaluated by wafer curvature method and grazing-incidence X-ray diffraction method respectively.The adhesion strength of TiN films was evaluated by scratch adhesion tests.The hardness of the thin films was measured by ultra-micro hardness tester.The wear resistance of TiN film was measured by a ball-on-disk wear tester.The morphology of TiN film was observed optical microscope and atomic force microscopy(AFM).The evolution of these film properties at differently aged times were studied.The results indicate the compressive stress of TiN films prepared under-50 V and-150 V substrate biases fluctuated within the range of 3.12 to 3.39 GPa and 7.40 to 7.55 GPa within 1 hour after the completion of deposition,and the film compressive stress did not change significantly.1-7 days after deposition was completed,the average daily decrease was 28.57 MPa and 35.71 MPa,and the average daily decrease was 2.08 MPa and 2.50 MPa for 7-30 days.The average daily decrease was 1.67 MPa and 7.00 MPa for 30-60 days,,the average daily decrease was 1.00 MPa and 5.33 MPa,The compressive stress of the film decreased continuously,and both showed a trend of rapid decline in the early stage and a gradual slowdown in the later stage.After 90 days of natural placement,the stress was basically released and the film properties remained basically stable.Based on the experimental findings,a great influence of stress release on the properties film adhesion,other mechanical properties and microstructure,such as the adhesion gradually degrades and the hardness of the films reduces with natural aging time increasing.