Microellipsometric surface measurement

Surface measurement is an important tool for quality control In our contribution we describe a novel application of reflection ellipsometry to profile measurement and material detection. The ellipsometric parameters (Delta) and (Psi) are measured by using a PSA-ellipsometer arrangement and a 4- zone-intensity-ellipsometric algorithm. To achieve a high lateral resolution we focus the laser beam on the surface through a microscope objective with high numerical aperture. The spot diameter is in the order to 1 micrometers . The focus adjustment is carried out by an integrated autofocus system. From the ellipsometric parameters we conclude to the refractive index of the local surface material and the local surface gradients. The height profile is calculated by an integrating and filtering algorithm. The material is ascertained form the refractive index. The feasibility of our novel microellipsometric measurement system is demonstrated by several tests. Measurements of material transitions and the height profile of a glass surface standard are presented.