Theoretical and experimental comparison of different techniques to characterize surface roughness

Characterization of surface roughness remains today a crucial problem, in particular in the fields of optics and mechanics. Many techniques [1] have been developed in this aim, and involve scatterometers or profilometers. However the measured roughness values may strongly vary from one technique to another, and it becomes necessary to normalize the statistical parameters that describe surface defects. In this paper we present experimental results obtained from 3 techniques that are Angle-Resolved light Scattering measurements (ARS), mechanical profilometer (Talystep) and Atomic Force Microscope (AFM). Moreover, a theoretical tool is provided for a detailed investigation of the apparatus functions relative to the light scattering and Talystep techniques.