Thickness dependence of grain size and surface roughness for dc magnetron sputtered Au films

The grain size and surface morphology of sputtered Au films are studied by x-ray diffraction and atomic force microscope. For as-deposited samples the grain growth mechanism is consistent with the two-dimensional (2D) theory, which gives relatively low diffusion coefficient during deposition. The annealing process demonstrates the secondary grain growth mechanism in which the thickness dependence of grain boundary energy plays a key role. The surface roughness increases with the increase of grain size.