Depth-sensing indentation modeling for determination of Elastic modulus of thin films

There are various methods to address the problem of determining the hardness of thin films when the substrate is involved in the deformation process produced during conventional indentation tests. For the determination of the elastic modulus using depth-sensing indentation methods, the problem is more complex due to the deformation of the equipment that comes in addition to the effect of the substrate. In the paper we discuss the use of Oliver and Pharr's method to take into account the deformation of the equipment for the measurement of the elastic modulus of TiCN thin films. For micro-indentation tests we proposed a new model to precise the effect of the substrate. The elastic moduli that are calculated are in very good agreement to those found in literature. For nano-indentation tests it is necessary to correct the data to take into account the shape of the indenter tip. We show that this correction, proposed at the origin for massive materials, is not able to explain the discrepancies between the calculated values and those coming from the literature for the elastic modulus of thin films. (C) 2009 Elsevier Ltd. All rights reserved