[摘要]：The fracture toughness, hardness, and Young's modulus of tantalum thin films are investigated based on nanoindentation measurements. A lower estimate of the fracture toughness of a 100 nm tantalum film is 0.28 +/- 0.07 MPa m(1/2). The hardness increases when reducing the film thickness whereas Young's modulus decreases slightly. More precisely, the hardness of the 100 nm thick film is four times higher than the bulk behavior. A simple theoretical model, based on the connection between Young's modulus and melting temperature, predicts an inverse grain size variation in Young's modulus confirmed by experiments. (C) 2010 American Institute of Physics. [doi:10.1063/1.3496000]
