Evaluation of Hardness of Superhard Thin Films by Analysis of Indentation Behavior with a Vickers Indenter

To evaluate the hardness of Diamond-like carbon (DLC) thin films formed by ion beam assisted deposition, the indentation load-depth behavior of some materials were tested using an ultra-micro hardness tester with a Vickers indenter. The hardness constants related with the Vickers hardness and the elastic modulus of the materials used were defined, similar to Meyer's law. The evaluation using the hardness constants was applied to TiN thin films of three different thickness on glass plate and the raw hardness of TiN thin films which was independent of film thickness was determined. Furthermore, the hardness of DLC thin films formed with different methods on two substrate materials was discussed. From these results, it was concluded that the hardness evaluation method for the thin films in this paper was useful.