Mechanical Spectroscopy and Structural Evolution of Thin CuMo Films

It is well known that in thin metallic films, the anelastic and the elastic properties show some characteristic features linked to the specific microstructure. The studied films Cu30Mo70, with a typical thickness of 200nm are deposited by Ion Beam Sputtering (IBS) on oxidised silicon (100) substrates. The measurements are performed on a vibrating reed device adapted for thin adherent films over a temperature range between 20°C and 450°C. This paper reports the combined results of internal friction, elastic modulus and internal stresses measured during thermal cycling. "Direct" observations of the microstructure are performed by X-Ray diffraction. We have correlated the modifications of the mechanical properties with the structural evolution of these metastable systems