Intrinsic stresses in compositionally modulated Au-Ni thin films and the supermodulus effect

Abstract

The stresses that arise in compositionally modulated Au-Ni thin films as a result of the constraint of the substrate were determined from the curvatures of micrometer-scale bilayer cantilever beams consisting of a silicon dioxide layer upon which the metal film had been deposited. These substrate interaction stresses were found to vary strongly with the wavelength of the composition modulation. Simulations of the bulge test show that such stresses can account for the major features of the “supermodulus effect” as artifacts of the analysis method.