Chemical mechanical planarization is a process that can smoothen topography or various materials It is used to planarize oxide, poly silicon or metal layers in order to prepare them for post-lithographic steps, avoiding depth focus problems during illumination of photosensitive layers. The tool includes a two-carrier system for polishing and planarizing single wafers with diameters up to 200mm as well as for coupons and part wafers (irregular-shaped samples).