EIS and Microstructural Studies of TiN Coatings Deposited by PVD d.c. Magnetron Sputtering

Abstract

This work reports the electrochemical and microstructural behavior of TiN thin films prepared modifying the nitrogen fraction XN2 and the target power WB in a PVD d.c. magnetron sputtering system. EIS tests along with structural analysis by AFM and SEM shows that the coating thickness by itself is unable to explain the properties of the TiN coatings, also the microstructure plays an important role on the definition of corrosion behavior of the films. The thicker, denser and flatter coatings reveal the best corrosion resistance in long immersion time, showing low capacitance Cd (between 19-86 μF cm- 2) and high resistance Rct values.