MEASUREMENT By

A non-contact on-site surface roughness measurement method was investigated in experimental and simulation approaches. The resolution of the vertical surface roughness was obtained at 20 nm by using self-interference theory. Various surface roughness measurement techniques, such as mechanical stylus, AFM and Michelson interferometer, were employed for different roughness samples. The novelty of this study was to measure the surface roughness on a rotating sample. For each sample with different step height, corresponding intensity distribution data was obtained and analyzed. The fringe visibility ratio resulted in a curve that is related to the step height, which represents the roughness. The results from simulations for all samples were compared with experimental data. Good agreements were obtained for the studied conditions. i