An AFM study regarding the effect of annealing on the microstructure of gold thin films

The effect of annealing on the microstructure of gold thin films was investigated with contact and tapping mode atomic force microscopy (AFM). A 200 nm thick gold thin film on glass substrate was annealed at three different temperatures (230, 280 and 420 °C). The changes in the microstructure of the thin film - the grain shape and distribution - was examined and compared before and after the treatment with AFM. The effect of the annealing was evaluated by various surface topography and texture parameters, such as surface roughness, skewness, kurtosis, surface ratio and also with a recently introduced parameter called localization factor. We found that the localization factor - which aims to describe the shape of the structures e. g. grains on the surface - could be used to quantitatively characterize the effect of the annealing, while we found the other evaluated parameters unsuitable for the univocal differentiation of the surfaces before and after the thermal annealing.