We present a detailed study of the surface roughness of a computer hard disk using atomic force microscopy and light scattering. The power spectrum density analysis showed that the surface possesses an anisotropic scaling behavior and has both random roughness and periodic roughness components. Quantitative anisotropic correlation length (ξ) and roughness exponent (α) for the directions parallel and perpendicular to the grooves are obtained. A novel in-plane (measurement parallel to the sample surface) light scattering technique is shown to be particularly useful for the analysis of the rough surface parallel to the grooves.
Read full abstract