Abstract: A two-step penetration method using the microind-entation technique is presented to investigate the mechanical properties of thin films. According to the method, a larger load indentation is employed to exhibit the influence of substrate deformation and film thickness on the measured hardness values, then a smaller load selected corresponding to the first step and with which the measurement will not be affected by the substrate is applied to measure the authentic hardness and elastic modulus of the films. Experiments with TiN films deposited on high speed steel, metallic nickel films on single silicon and (Ti,Al)N/VN multilayers show that by using this method, the mechanical properties of most different films can be measured accurately and reliably. Additionally, the results of the experiments on (Ti,Al)N/VN multilayered thin films using this method indicate that there exist superhard and supermodulus effects in this system.

Key words: Elastic modulus, Hardness, Nanomultilayers, Thin films, Two-step penetration method