We compute Young's modulus from force-distance curve analysis performed in 15 different locations for each sample. Similarly, we determine the surface stiffness as the slope of the force-separation curve in the contact region from approach-retract curves resulting from nanoindentation processes. The results can be found in Table . For both DC and HiPIMS methods, there is a decreasing trend of Young's modulus with the deposition time. This trend appears due to the measurement method, which is highly dependent on the tip-surface interaction. Consequently, the decrease of the Young's modulus has different explanations depending on the power supply. For DC power supply, the columnar deposition which is gradually formed with the increase of the time deposition strongly influences the tip-sample interaction due to holes created between the columns. Therefore, the measured Young's modulus decreases because of this columnar character of the films. On the other hand, in the case of the HiPIMS power supply the films are very thin and the interaction between tip and the sample surface is strongly influenced by the substrate.